50b BBS i iiiil I 11 FORGED STEEL WATER-TUBE MARINE BOILERS Manufactured by THE BABCOCK & WILCOX CO. NEW YORK, U. S. A. BABCOCK & WILCOX, Limited LONDON, ENGLAND HIGHEST AWARD, GRAND PRIX, EXPOSITION UNIVERSAL PARIS, 1900 r T -« SECOND EDITION FIRST ISSUE NEW YORK AI^Ip:..i'.qNDON Copyright 1914 r.v Thf Bahc 1^ ^ N PJ N ro ^^IS a » »* -t^ »" * »" -H^ +^ •T- -T- oj eg ^ u °a° o «j ^ 1/) Oi o 00 IN " m' n " ■-> rJ ri M M wK o Vt-I L-**-! 5 o u v -o 00 1« „ !S o „ ^ O OO u ? IT) to OO vq '? r^ oo o p3 VW^MH a -d -d d. ro 4 4 cr^ ij E! -« ^ M 00 M o> ~- ■> _^ -^ .^^ — •§ H lO -o u-j rv5 o ^ rj- to "'o>"''t 1 1 1 ; •* J ■o o O O O fO C4 ro <3 O 1^ 1 1 1 N ro M (N " !N M M M M M M 1 1 1 IH M ^ o d o d 33 o ^ 6^ 33 1 1 1 d d o 1 — '^ ^ ^ — ' — ^ ^-^ ^ ^-^■^^ *-^>^- 00 -O wo N O ^ O 00 M O N O N O M O 23 M M ll M M M M H M 3 d d d d d d d d d d d d d d d d d o Z2 ^7^ zz ^, 2; ;z; 2:2; a;z ZZ ^2:1 •.^v-. ■ —— ■ ■ — ,— — ~ *— v^ . J^ « S ; i ^:s ^;s ':s ^ % •d M M o "S ^•^ K f^ "r^ V n J;1 M M H z M 7" ^ ^ ^ ^ 13 ^ ^ ^ 5."^ k J f ^ \ J ^ O " o r^ M 00 "■PO ^ "oo "V Vj "n w '^'^ Nt "■* "^^ jd ^■^ j ; "„ ; \-f 'S: v* J ;^ 60 C " " o " M M 'o. d "ov t^ 0) "Oi "■q '■^ "o-i "■q "n ~b "o\ "n "tN *~* *~* *~* " " " ■^ ?f o o -o o o o o o o •^ oi'— o t^ 00 o o o o St; r^ o r^ <3 Oi lO 00 £ 3 P* r^ 'T fo '^■ rf ■!f -* Km a , ^ — CO bo >. I- oi ^ O 3 'o ^ & ■J^ H BB Q d CQ d "o •d d c +-> d •d 1 m d m d rs •^ pa "? ■d H ' — ' H W ^ ^ •*M H c M a m 0\ =a =a "■ tD "o ^ H o H h5 2 > 39 < K o « H u (-1 B) n 40 DREDGES FITTED WITH WATER-TUBE BOILERS PERHAPS in no other industry is the underlying prineiple of com- mercial efficiency so slightly defined and unrecognizable as in the work of dredging. The number of hands required to operate the dredge is relatively small; and, unlike the power plant of a large mill or factory, when the plant shuts down few people are rendered idle. Delay results in no damage to the material and the work can be taken up again at leisure when repairs or overhauls are finished. It is not strange, therefore, that in the minds of many designers of dredging installations "first cost" assumes overwhelming consideration. With them it is not a question of how continuously the plant is to be kept in operation, but of how cheaply it can be built. Second-hand machinery is often used and there is no type of steam generator that cannot get a trial, provided it can be purchased for little money. And yet, on the other hand, in no other industry is the saying "Time is money" so forcibly true as it is in dredging. Particularly in the light of active competition in bidding for contracts, the operator who makes his plant pay the largest return on the investment is he who keeps his dredge ceaselessly at work at Jiill capacity, days and nights, one hundred and sixty- eight hours a week. An inconspicuous lack in steaming ability, slightly fewer revolutions per minute and slightly fewer cubic yards per hour will, in the aggregate, mean the loss of many thousands of dollars; and a brief shut-down for renewal or repairs may offset many times over a very con- siderable difference in first cost. Ample steam capacity and economy of fuel are very vital features to be considered in the building of a dredge, and the value of a durable, dependable boiler that will keep things moving all the time at full power cannot properly be figured at so many cents per pound. To supply a suitable boiler for dredges, both stationary and those of the self-propelling, hopper type, a special class of Babcock & Wilcox boiler has been designed possessing features which specially commend it for this class of work. The illustrations show a sectional side view and a perspective view of such a boiler, from which it will be noted that, in its general characteristics, it is similar to the usual "Alert" design of Marine Boiler, that is the boiler is fired from the low end and there is the same system of baffling. The tubes, however, are all 4 inches in diameter No. 8 B. W. G. (0.165") thick and of much greater length. This is usually 12 feet but may be made 14 feet where special circumstances require it. It will be noted also that the usual water-boxes on the sides have been omitted and are replaced by brickwork. This boiler has the same large furnace, increasing in volume towards 41 the bridgewall, and, like the Alert design, is equally adapted to burning coal or oil fuel. This boiler is of unusually robust construction and can, therefore, be depended upon for thorough reliability under the trying conditions which usually obtain upon dredges. As will be seen by the following illustrations and descriptions, boilers of this class have been extensively used and have given great satisfaction. BABCOCK & WILCOX DREDGE BOILER— PATENTED Longitudinal Section 42 .--•^^SiH- BABCOCK & WILCOX DREDGE BOILER-PATENTED 43 44 RUvSSIAN GOVERNjMENT DREDGES FIRED WITH NAPHTHA A novel feature in the dredges shown in the accompanying photograph, which have been built by Messrs. La Societe Anonyme John Cockerill of Seraing, for the Russian Government, is the installation of water-tube boilers. These are of the Babcock & Wilcox marine type, and have given on the trials very great satisfaction. U. S. ARMY DREDGE " NEW ORLEANS ■'—BABCOCK & WILCOX BOILERS, 3000 I. H. P There are four of these boilers on each hull half, making eight in all, having a total heating surface of 17,200 square feet. In addition to this, a small boiler of the same construction is fitted in a stern-wheel steamer, which is to act as a workshop and general tender to the dredge; this boiler has 1000 square feet of heating surface. On the Russian official trials, which took place on the 24th to 29th of May, 1900, the boilers worked throughout without a hitch, giving an abund- ance of perfectly dry steam. On the full power trial, with all the machinery running, no trouble was experienced in keeping the water level constant, or in getting a sufficiency of steam, although working at a very high rate of evapora- tion, which would be, judging from the indicated horse-power of the engine, nearly 8 pounds of water per square foot of heating surface per hour. On the stern- wheel steamer, with the boiler of 1000 square feet heating surface, the boiler was forced to about double its rated capacity. 45 The boilers are fired exclusively with naphtha; there are four burners fitted to each boiler in the dredge, and two to the boiler in the stern wheeler. The burners are made so as to swivel out from the furnace when requiring to be cleaned or examined. The spraying of the petroleum into the furnace is accomplished by a jet of steam. The oil by this means is atomized and made ready for combustion. The temperatures taken of DREDGE •• LYONS" Working on New York Statk Bakck Canal. Owners: Crowell, Sherman, Stalter Co. Babcock & Wilcox Boilers, 2000 I. H. P. the funnel gases showed these to be very low, /. c, not more than about 500 degrees F. One of the advantages derived from the use of these boilers is the small amount of weight, as compared with ordinary boilers. The weight of the four boilers on one hull half, complete in working order with funnel, up- takes, and all accessories, was .02 tons per indicated horse-power developed on the trial. 46 FUEL— ITS COMBUSTION AND ITS HEAT VALUE THE term "fuel," in its widest sense, may mean any substance which, by its combination with oxygen, evolves heat. It is generally applied, however, to those substances which are in common every-day use for heat-producing purposes. Coal is the fuel most extensively used, and while saw-dust, rice-chaff, bagasse, wood, etc., are not uncommon fuels for making steam on land, coal is practically the only solid fuel that need be considered in marine practice. The nature and cjuality of coal, in point of view of its heating value, vary considerably. It is a fossil of vegetable origin, and the difference in its nature is attributed to the variation in its origin. Coal from the same stratum does not vary in its nature or characteristics, and generally these characteristics are the same in a certain district, hence the district from which a certain coal is obtained usually determines its commercial designation. Coal is divided into two main classes — anthracite and bituminous. "Anthracite" is a word of Greek origin, meaning "carbon" or "coke," the fuel being so named probably because it is that which con- tains the largest percentage of fixed carbon. "Bituminous" is of Latin origin, meaning "containing or resembling bitumen." There are various degrees in the nature of these coals, which may be enumerated as follows: Anthracite, or hard coal; semi-anthracite; semi- bituminous; bituminous, or soft coal; and lignite. Pure anthracite coal — which is said to be the oldest and deepest formation — is found principally in the United States of America. It is also found in the western part of the South Wales coal fields; in the neighborhood of Swansea; in some parts of Scotland; to a small extent in France; in the South of Russia; and in the Osnabriick district of Westphalia, Germany. Semi-anthracite coal closely resembles anthracite in its physical characteristics and appearance, but contains less fixed carbon and burns more freely. It is represented by what is known as "Welsh anthracite," and by coals from a limited territory in Pennsylvania. Semi-bituminous coal is most largely represented by the "Cardiff" or "Welsh" coals from the enormous fields of South Wales, and in the United States by the rich deposits on the slope of the Appalachian Moun- tains, extending from Clearfield County, Pa., to the southern boundary of Virginia, the coals in this belt taking the names of " Pocahontas," " George's Creek," "Clearfield," etc. The Belgium coal, known as "Demigras," is also of this class. Bituminous coal is found almost all over the world. The largest known 47 L LU-_._..Jl^ L .^ILiL. 48 fields, generally speaking, are in Scotland, England and the United States. It is found in less quantity, in Germany in the Ruhr district, in West- phalia and Silesia, in the north of France, Austria, Russia, China, Japan, India, Australia, New Zealand and Canada. "Cannel" coal, a variety of bituminous coal, is found in the Midlands itt^ ___ 1 • i 1 Im bhl ,4:^Mi Wm^^^- 1, : M '«*■»■- 3 i- !- ^ ^% \ '-^ "^ )^y-- ■ |[^B^S^ I^S Copyright by N. L. Stebbins UNITED STATES ARMORED CRUISERS— " MONTANA" AND "NORTH CAROLINA" Babcock & Wilcox Boilers, 31,000 I. H. P. of England and in the United States. It is used principally for making illuminating gas and for domestic purposes. The principal lignite fields are in France, Italy, Germany and Austria, but Hgnite is also found in the United States and in Sweden. The theoretical heating value of fuel is the heat which it develops w^hen consumed under theoretically correct conditions — which are practi- cally only obtained in the laboratory — and it is expressed in heat units or thermal units. In England and the United States of America the British thermal unit is adopted, this being the amount of heat required to raise the temperature of one pound of water one degree Fahrenheit. On the Continent of Europe the "calorie" is used, and the standard 49 50 is the heat required to raise the temperature of one kilogram of water one degree Centigrade. To convert calories per kilogram of coal into British thermal units per pound of coal, multiply by 1.8. The theoretical heating value of the above-mentioned coals varies betv/een 7000 and 15,500 British thermal units per pound, depending largely on the varying amounts of incombustible matter or ash that the coals contain. The semi-bituminous coals of the Pocahontas and Cardiff varieties are the most uniform in this respect, the ash being only 3 to 8 per cent.; Belgian "Demigras" will run from 5 to 15 per cent., while the residue in Transvaal coal may reach 25 to 35 per cent. The anthracite coals, as mined, contain from 15 to 30 per cent, of refuse or slate. Most of this, however, is usually removed when the coal is prepared for the market, so that anthracite, as sold, may contain as little as 3 per cent. On the other hand, the smaller sizes may run very high in ash, and cases have been known where 50 per cent, refuse has been found in boiler tests. Bituminous coals are extremely variable, running from 5 to 35 per cent, ash, while the percentage in lignite is usually considerably under 10. The heat value of the combustible portion of the coal (ash and moisture deducted) is also quite variable, and depends on the quality of the volatile matter, which may be either very rich in h3'drocarbons, as in semi-bituminous coals, or comparatively high in oxygen, as in many of the bituminous coals and lignite. So much, in fact, does the amount of oxygen found in lignite detract from the calorific value of the volatile matter, that the combustible portion of lignite is worth only about three- fourths that of semi -bituminous coal. APPROXBIATE CHEMICAL COMPOSITION OF SEVERAL TYPICAL KINDS OP SOLID FUELS Wood, perfectly dry Wood, ordinary Peat Charcoal , Straw Coal, anthracite Coal, semi -bituminous Coal, bituminous, Pittsburg . . . Coal, bituminous, Hocking Val ley, O Coal, bituminous, Illinois . . . . Brown coal, Pacific coast . . . . Lignite, Pacific coast Moisture Carbon Hydrogen 50 6.0 20.0 40 4.8 30.0 40.6 4.2 12.0 84 I.O 16.0 36 50 I.O 86 I.O I.O 84 4.2 14 75 5-0 7-5 67 4.8 I I.O 56 50 16.8 50 3-8 14.0 55 4.0 O.xygen Xitrogen Sulphur 41-5 1.0 33-2 0.8 21.7 38.0 I.O 0-5 0.5 34 0.8 0.6 8.0 I.O 1.6 10. 1.2 1-5 1 1.0 I.O 30 13-6 0.9 15.0 I.O I.O 1-5 1.2 3-5 3-0 5-0 10. o 6.0 8.0 8.0 13.0 13.2 50 51 ^ ^ u 5 I 52 The elements in the coal from which we derive heat are carbon in its sohd state, hydrogen, and sometimes a Httle sulphur. The hygro- scopic water which it contains is injurious, as it absorbs heat for its own evaporation. The heat value of the fuel may be calculated from the analysis by means of Dulong's formula, as follows: B.T.U, per pound equal 146 C+620 (H-JO) + 40 S in which C, H, and S are, respectively, the percentages of carbon, hydrogen, oxygen and sulphur in the fuel, and the constants are the most recent average heat values for carbon, hydrogen and sulphur, each divided by 100. The actual heating value of a coal, as determined by test with an in- strument known as a "bomb calorimeter" (see page 71), agrees very closely with that calculated from the analysis, usually within 2 per cent., when both the analysis and the calorimeter test are made by a skilled chemist. The analyses given in the foregoing table are called "ultimate analyses," since the constituents of the fuel, except the moisture and ash, are re- duced to the ultimate chemical elements. Another kind of analysis, called "proximate analysis," is more commonly used, which separates the coal into four parts, viz. : moisture, volatile matter, fixed carbon and ash. The proximate analysis is of great value for indicating the general character of a coal. By dividing the percentages of volatile matter and fixed carbon each by their sum, we obtain the percentages of each in the "combustible," or coal dry and free from ash. These percentages serve to identify the class to which the coal belongs, as follows: Class of Coal Fixed Carbon per cent, of Combustible Volatile Matter per cent, of Combustible Anthracite Semi-anthracite 100 to 92 92 to 87 87 to 75 75 to 50 below 50 to 8 8 to 13 13 to 25 25 to 50 over 50 Semi-bituminous Bituminous ... Lignite These various kinds of coal act very differently during their com- bustion in a furnace, and to get the best results each must be handled in the way best suited to its characteristics; and the size and design of the furnace must also be adapted to the particular requirements of the coal. With anthracite coal disintegration and distillation take place very slowly, with semi-bituminous coal they take place somewhat faster, and 53 54 with bituminous coal almost instantaneously, the rate depending on the percentage of fixed carbon. For the combustion of one pound of carbon 2.66 pounds of oxygen are necessary, and as the air contains only 23 per cent, of oxygen, it follows that 1 1 .6 pounds of air are necessary for the combustion of one pound of carbon. The air required for combustion in a boiler furnace has to pass through the spaces between the grate bars, and the layers of fuel on them, the rapidity with which it passes through depending on the intensity of the draft and condition of the fire. When the fuel is supplied in too great a quantity, or the supply of air is insufficient, the carbonic acid, formed in the lower layers of the fuel, takes up another portion of carbon in the upper layers, and forms carbonic oxide or carbon monoxide, which passes through the boiler unconsumed, and frequently re-ignites at the top of the funnel, where it comes into contact with sufficient air to enable its combustion to be completed. Thus, flaming at the top of the funnel or in the flues beyond the boiler, is gener- ally a sure sign of unsatisfactory conditions of combustion. Anthracite coal, and coke, may be called comparatively slow com- bustion fuels, and to provide that a certain quantity shall be consumed for a given size of boiler, either the grate surface must be increased, as com- pared with bituminous coal, or the intensity of the draft — in other words, the velocity of the air supply — must be increased. From this arises the fact that when burning anthracite coal in a boiler furnace proportioned for bituminous coal, either an extra high funnel is required, or an artificial method of intensifying the draft commonly called "forced draft," must be used. Anthracite and semi-anthracite are the coals for which it is easiest to design a suitable furnace, and experience has shown that with all types of boilers, for these fuels the plain level grate is the most practical; it is the cheapest in up-keep, and it requires the least skill on the part of the fireman. Naturally, the size of lump, the percentage of ash, the rate of com- bustion required and the strength of draft, determine such details as width of bar, extent of grate surface, form of bar, and size of air opening. With semi-bituminous coal, ow4ng to its larger percentage of volatile matter and the rapidity with which this infiammable gas is distilled off, more space must be provided in the furnace and care taken to prevent the burning gases coming in contact with the boiler heating surface and being cooled before combustion is complete. These points are still further accentuated in relation to bituminous coal and lignite, and neglect to observe their importance leads to great loss in the use of these fuels. The best methods of handling semi-bituminous coal and the bitumin- 55 ous coals having the larger percentage of fixed carbon, is to fire it on the front end of the grate, where it is "coked," the volatile gases passing back over the incandescent fuel and burning completely before touching the heating surface. The coke left on the front is then pushed back and a fresh charge of coal fired. With the very volatile bituminous coals and lignite, it is impossible to handle the fuel in this way, as it does not coke and has a tendenc}' to form bad and troublesome clinker when worked with the fire tools. This fuel should be spread in very light charges evenly from the front to the back, covering each half of the grate alternately. Semi-bituminous and the coking variety of bituminous coal may also be fired in this way with no loss in economy if the firing is skillful. The method of firing and the design of the fur- nace have a material effect on the production of smoke ; but it may be mentioned that while smoke is an in- dication that the conditions of combustion are suscep- tible of improvement, an absence of smoke is not by any means a sure sign of proper combustion, for it may be brought about by too much air being supplied, and consequent dilution of the gases; nor is the pro- duction of smoke by any means an indication that much waste takes place, for the quantity of unconsumed carbon sufficient to color the escaping gases from a boiler is an exceedingly small percentage of the total amount of fuel. The Babcock & Wilcox Marine Boiler, here illustrated, is the best of all water-tube boilers, so far designed, for obtaining a high efficiency with bituminous coals. It will be seen that the gases evolved from the fuel, pass under the roof located over the front portion of the lowest row of tubes, to a high com- bustion chamber at the rear, and are thoroughly mixed and burned before entering the bank of tubes forming the heating surface. Generally speaking, with this boiler and with careful firing and favorable conditions, from 70 to 75 per cent, of the heat units which RTLETT 4 CO , N.Y. | 56 a coal is found to contain theoretically, can be transferred to the water and steam. Claims have been made that more than this can be obtained — up to 80 per cent. — with certain classes of boilers; we do not wish to dispute the possibility of obtaining this, but certainly it is only obtainable under conditions which are so carefully studied as to be impracticable or im- possible to maintain in ordinary practice. The remaining 30 to 25 per cent, is lost in radiation, in the heat carried away in the waste gases, and in im- perfect combustion, due either to unavoidable excess of air in the furnace, or to a lack of sufficient air, depending upon the furnace conditions. A greater proportion of the heat can usually be saved and utilized when anthracite and semi-bituminous coals are employed. And as the volatile matter in the fuel increases, the greater becomes the probable loss from incomplete combustion. Higher evaporative efficiencies can generally be obtained from water- tube boilers than from shell boilers, for the reason, principally, that in the former there are furnaces which are capacious, and in which combustion takes place more quickly than in the furnaces of shell boilers, where not only is the space for combustion confined, but the fuel surrounded by cool boiler surface. STEAM WHALER " MARY D. HUME" IN THE ARCTIC Owners: Pacific Steam Whaling Co. (From " The Frozen Northland " by WiNFiELD Scott Mason, by Courtesy of the Author.) Babcock & Wilcox Boiler, 400 I. H. P. 57 (U >oo y, = g " ^ ^W c. s >Q«= oi ^ o Q z < o > oo OJ •"■ P3 rt _:^£) (nW ^ ; C « 1-1 m -+00 ro rO CN O N r^ -t 't c q^oo os I- 00 q q -; ■-< o o vd d d t---vd -t C 30 . P) OC' — PI vd d d r^ ■ P) O O rO -^ ro ■-♦• >C ro O t^ t^oo' Cv q. O O ro -t rO O liO lO PO •* IT; r<0 "" P) 00 « rO d CO .^ ""^ r-i •5 " " CO ■^"P q p) 00 t^ On P) PO pi -^ rOvd 1000 10 Tl- PO 10 PI vO J^OO 00 ro t^ c^ -t-'X PI 10 C On -t PI c i^ fc d d x r^ ^ O PI vO mx ON •+ iC 1^ PI o O O o - " "^ 2 4 r-MQ PI 00 O 00 PI I^ 'l-^ C PO PI vO 1^ PI q PI 10 10 C O^O PI fO o C -f I--X Cn i-h' W K H hJ 5) pq ?• < H u M u 7t < U rn U ^ '5 o X) <- 2-5 . 14-, ■*-' C S-' "5 !/) O "^j O - - "U O ■•5 W) w O (U *-' 1-^ v-, ctj c CD rt _0 ^ (^ rt a! 3 'o 'o 3 ^QGfqpqtiH 00. rt rt (u U) t/3 V-, MM = ni nS aj OJ (L> u ffiEO y 3 5 u I-. "5 o rt rt — ' ^ ," h t tw) ^ t/j t- c3 cd g* l-( O O O rt ^ S g > C 3 o i- .5 .5 o ^030 ^^ vt. tM jj *j rt C O O CJ O O cj 3 > > > > > -5 c o O O O C'o rt rt rt rt rt ' o 0.00000"^ ^ >, fc" ■4-» -fcJ -4-> ■*-» -1-J O p c c c c c c 000000 O O O O O -TJ V- u t-. 1-. u. irj ■ o o o o o *t: K Ch e, CL, CL, (1, W tu o •'^ g S^> M ^ o t o o o u « M-^ £i ^ II tS ^^ ^ o .i: rt - c S rt M^ rt o rt o P t/i c C C !S Lh 3 u 3 So o c o o I Vh U W. k. I 3333' rt rt rt rt I k- k- I-. u . 0000 cx a. 0. o, E E E B 0000 58 HEAT VALUES OF COAL B.T.U. PER POUND OF DRY COAL— CALORIES PER KILO. DRY COAL UNITED STATES Name and Locality of Mine Alabama: Blue Creek, mine run. Henry Ellen, lump . Mary Lee Pratt, lump .... Old Pratt, No. 4, lump Arkansas: Coal Hill Eureka Lignite Colorado: Diamond, Jerome Park New Caste, mine run Illinois: Paisley, screenings Pana, screenings . . Big Muddy, lump Ladd, lump .... Staunton, lump . . Seatonville, lump . . Streator, lump . . . Streator, screenings . Wilmington, screen ings Wilmington, washed screenings .... Indiana: Brazil, block .... New Pittsburg . . . Brazil, semi-block . . Indian Territory: McAleester, slack . . McAleester washed slack Krebs, lump .... Kentucky: Vanderpool, lump . . Maryland: George's Creek . . . Eureka Cumberland, mine run Cumberland, mine run Missouri: Hamilton Frontenac, lump . . Glen Oak B.T.U. 11931 13608 13314 12835 14580 13452 12254 921S 13103 12069 10942 10565 13400 12450 11508 12000 12600 12200 97SO I3I00 13629 12369 12500 10903 12874 I4216 13652 13660 I43I3 I1662 9743 9767 Calo- ries 6628 7560 7397 7131 8100 7473 6808 5119 7280 6705 Authority 7444 6917 6393 6667 7000 6778 S417 6722 7572 6872 6944 5840 6057 7152 7898 6479 5413 5426 W. B. Phillips The B. & W. Co. I St. Louis Sampling 5 Works B. &. W., Ltd. I Carpenter f^ll I 1 The B. &. W. Co. > Carpenter I Noyes, McTaggart ( and Craven Carpenter St. Louis Sampling Works Carpenter i Barrus [TheB. & W. Co. Forsyth I St. Louis Sampling ( Works Name and Locality of Mine Ohio: Brier Hill, lump. . . Jackson, lump . . . Cambridge Hocking Valley, lump Hocking Valley, mine run Palestine .... Salineville .... Yellow Creek. . . Waterford .... Pennsylvania: Anthracite Buck Mountain, buck- wheat Cross Creek .... Honey Brook . . . Avondale Drifton, buckwheat . Lackawanna .... Lykens Valley, buck- wheat Scranton Forty Foot. Bituminous Connelsville .... Duquesne, mine run. Catsburg eaver Creek . . . Carnegie Creedmore .... Hoytdale Turtle Creek . . . Pittsburg, nut and slack Youghiogheny . . . Tennessee: Glen Mary Crooked Fork . . . Virgini.a. and West Virginia: Elk Garden .... Pocahontas, Flat Top Pocahontas, mine run Thacker Fairmont, mine run New River, mine run Nuttalburg, mine run Thermont, mine run B.T.U. Calo- ries 13600 7SS6 13613 7563 13075 7264 13102 7279 12571 6984 13387 7437 13464 7480 13603 7557 13637 7576 12308 6838 11520 6400 11732 6518 13219 7344 13722 7623 12371 6873 1 1902 6612 130S0 7250 13683 7602 14285 7936 13858 7699 13450 7472 14047 7804 13640 7578 13403 7446 13547 7526 13280 7378 12941 7190 12542 6968 12542 6968 13180 7322 14800 8222 I43S5 7975 14182 7879 13830 7683 14488 8049 14800 8222 14352 7973 Authority Carpenter The B. & W. Co. >- Lord & Haas The B. & W. Co. !• Barrus Carpenter D. Ashworth ( Woodman Lord & Haas I The B. & W. Co. C Barrus Anonymous The B. & W. Co. Barrus The B. & W. Co. [Lord & Haas i The B. & W. Co. ENGLAND, GERMANY, FRANCE, BELGIUM, AND AUSTRIA-HUNGARY Coals, Locality of Beds B.T.U. Calo- ries Nature Coals, Locality of Beds B.T.U. Calo- ries Nature GREAT BRITAIN welsh coals Ebbw Vale, 1848 . . Powell Duffryn, 1848 Llangennech, 1848 . Llangennech, 1871 . Graigole, 1848 . . . Nixon's Navigation . 16214 15715 14998 14964 14689 15000 8998 8710 8318 8305 8152 8325 ) Almost pure an- L thracites, hav- f ing 84 to 89% J of carbon GREAT BRITAIN continued Gwaun Cae Gurwen. Newcastle Derbyshire and York- shire ...... Lancashire .... Scotch 15123 14820 13860 13918 12870 8402 8225 7692 7724 7150 Pure, hard anthra- cite ) Bituminous coal, V having 77 to I 82% of carbon Bitu. coal, having 78% of carbon 59 EUROPEAN COUNTRIES— COXTIXUED Coals, Locality of Beds GERMANY Rhenish Prussia: Dortmund, Ruhr coal Witten, Ruhr coal . Bochum, Ruhr coal . Bommern, Ruhr coal Essen, Ruhr coal . . Saar-coal Saxony: Zwickau Hohndorf Oelsnitz . Lower Saxony, An- HALT AND Brunswig Unseburg Atzendorf Neudorf Gorzig Halle a. S. Bitterfeld Naumburg Hanover: Osnabruck . . . Obernkirchen . . Silesia (Prussia) Carlssegen Myslowitz . Waterloa Konigshiitte Paulusgrube Waldenburg Brandenburg Neurode Freienstein. Maxgrube . Bavaria: Hanshamer coal . . Peipenberg Penzberg .... FRANCE: Anthracite de la May- enne Anthracite de Lamurc (Isere) Bassin du Pas-de- Calais: Maries Vully Hcssin Lens Nau.x .... L'Escarpelle . Les Courriferes Bassin de la Sa6ne: Blanzy Epinac Bassin de la Loire: Rive-de-Gier puits Henry Rivc-de-Gier, No. i Rive-de-Gicr, Cime- tiere i B.T.U I4SI8 15125 13514 13212 1498s iiSii 11964 1 1343 10674 5769 6444 6093 3853 416s 3830 4563 10789 12718 10422 10758 1 1412 12247 1242s 12637 12193 13393 9651 10087 9821 8186 15566 13782 15352 15258 15256 15400 1426s 13127 14086 IS481 IS472 Calo- ries 8066 8403 7508 7340 832s 639s 6647 6302 5930 3205 3580 3385 2140 2314 212H 2535 5994 7066 5790 5977 6340 6804 6903 7021 6774 7441 5362 5604 5456 4548 4956 8646 7657 7875 8400 8529 8477 8476 8556 7925 7293 7826 8601 8596 8os2 Nature ■^Cannel coal Short flame coal, semi-anthracite ( Cannel coal -Cannel coal ^ Brown coal or lig- nite, low grade Semi-anthracite, low grade Bituminous I Long flaming, > scmi-bitumin- I Lignite or brown i coal, low grade Anthracite I Bituminous, hard 5 coal Bituminous, coking Bituminous, hard coal I Bituminous, i coking Semi-bituminous coal Semi-bituminous coal, long flame Bituminous coal, long flame Coals, Locality of Beds Bituminous, coal hard B.T.U. Bituminous, hard coal, long flame FRANCE continued: Bassin de la Loire: Rive-de-Gier, Cime- tiere 2 Rive-de-Gier Couson Bassin de l'Avevron : Lavaysse Ceral Calo- ries 15309 14770 14630 13203 8505 8206 Nature •Bituminous, hard coal, long flame Bituminous, hard coal, long flame Semi-bituminous coal Bassin d'Alais Roche- belle 15643 8691 Bituminous, coking Bassin de Valenci- ennes: Denain Fosse Renard. Denain Fosse Lclvct i Denain Fosse Lelvet 2 St. Wast, Fosse de la Reussite .... St. Wast, Grande Fosse St. Wast, Fosse Tin- chon Anzin, Fosse Chauf- four Anzin, Fosse la Cave. Anzin, Fosse St. Louis Fresne, Fosse Bonne- parte Vieux-Cond6. Fosse Sarteau BELGIUM Bassin de Mons: Haut-flenu .... Belle et Bonne, fosse No. 21 Levant du flenu . . Couchant du flenu . Midi du flenu . . . Grand-IIornu . . . Nord du bois de Bossu Grand-Buisson . . . Escouffiaux .... St. Hortense, bonne Bassin du Centre: Haine St. Pierre Bois du Lac . . La Louvicre . . Bracquegnies Mariemont . . Bascoup . . . Sars-Longchamps Houssu .... Bassin de Charleroi : St. Martin, Fosse No. .} ■ Trieukaisin .... Poirier, Fosse St. Louie Baycmont, Fosse St. Charles Sacr6- Madame . . . Sars-les-Moulins, Fosse No. 7 . . . Carabinier-francais, No. 2 Roton. veine Grcffier Pont-du-Ioup . . . 15244 15100 15316 iSios IS188 15082 I43S3 I4S49 15397 15228 15409 14576 14326 14508 14446 14553 14943 14407 14877 IS2I7 15107 14702 14358 15127 15363 15168 1491 1 14895 14945 14954 15069 14421 13806 15204 14911 14311 14947 8469 8389 8509 8392 8438 8379 7974 8083 8SS4 8460 8561 8098 7959 8060 8037 8085 8302 8004 826s 8454 8393 8168 7977 8404 8535 8427 8284 «27S 8303 8308 R372 8012 7670 8447 8403 8284 7951 8304 'Bituminous coal, I long flame Bituminous coal, short flame > Bituminous, \ coking ( Semi-bituminous f co:-d Semi-bituminous, hard coal Semi-bituminous, coking coal [=■ tuminous, coal hard _ Semi-bituminous, coking Semi -bituminous, hard coal 60 EUROPEAN COUNTRIES— CONTINUED Coals, Locality of Beds AUSTRIA-HUX- GARY Lower Austria: Griinbach .... Thallern Upper Austria: Wolf segg- Trannt hal Stvria: Leoben .... Fohnsdorf . . . Goriach .... Koflach .... Wies Trifail .... Bohe.mia: Kladno .... Buschtehrad . . Libuschin . . . Schlan .... Rakonitz-Lubna Pilsen .... Schatzlar . . . Aussig Dux Bilin Brii.x Moravia: Rossitz .... M. Ostran . . . Gaya Goding .... B.T.U. IMS'? 7057 6006 9666 9187 6222 6867 7997 7SS6 1067s 8865 9900 7979 931S 9S52 6408 7808 8182 8274 I2S53 12623 4858 S056 Calo- ries 6366 3921 5370 S104 3457 38 IS 4443 4198 593 1 4925 5500 4433 4032 S177 5307 3560 433S 4546 4597 6974 7013 2699 2809 Nature Semi-bituminous coal Lignite or brown coal Lignite or brown coal Lignite or brown coal Semi-bituminous coal Lignite or brown coal ; Lignite or brown i coal Coals, Locality of Beds AUSTRL\-HUX- GARY continued Silesia P. Ostran , Orlan-Lazy Poremba Karwin . . Taklowetz Hungary Fiinfliirchen .'\nina . . Xeufeld . . Brennberg . Aika . . . Salgor-Tarjan Dorog-Annatha Tokod. . . . D.\l.matia Siveric . . . Istria: Arsa Transylvani.m Petrozseny Egeres. . . Bosni.\: B.T.U. 12564 12389 11057 13021 1 1932 10276 11356 5200 832s 6913 7966 7709 Zenica. Calo- ries 6980 6883 6143 7234 6632 5709 6309 2889 462s 3841 4426 4283 4483 5657 6270 4829 Nature Bituminous coal [ Cannel coal Lignite or brown coal Lignite or brown coal Lignite or brown coal Lignite or brown coal Lignite or brown coal TEMPERATURE OF FIRE The following table, from M. Pouillet, will enable the temperature to be judged by the appearance of the fire: Appearance Temperature Fahrenheit Appearance Temperature Fahrenheit Red, just visible Red, dull 977° 1290 1470 1650 1830 Orange, deep Orange, clear White heat White, bright White, dazzling 2010° 2190 Red, cherry, dull Red, cherry, full Red, cherry, clear 2370 2550 2730 MELTING POINTS OF METALS Substance Temperature Fahrenheit Metal Temperature Fahrenheit Metal Temperature Fahrenheit Spermaceti Wax, white Sulphur . . Tin .... 120° 239 Lead . . . Zinc . . . Antimony . Aluminum Brass . . . 625° 780 842 1 160 1650 Silver, pure . Gold coin . . Iron, cast, med Steel . . . Wrought-iron 1830° 2156 2010 2550 Bismuth . . 2910 61 62 ADVANTAGES OF LIQUID FUEL FOR MARINE BOILERS THE many advantages of liquid fuel or fuel oil for use with steam boilers have been apparent for a long time, and, in localities where the crude oil or refuse from distillation could be obtained cheaply (or where coal w^as very expensive, as in California) it has been used w4th much satisfaction. As far back as 1893, Colonel Soliani of the Italian Navy read a paper giving details of elaborate trials of petroleum refuse as fuel, and in 1902-3 an extended series of tests of various forms of burners w4th crude oil was made, under the direction of the late Admiral Melville, U. S. Navy, by a Board of Naval Engineers. In all of these tests, the oil was sprayed or atomized by steam or com- pressed air. Although excellent results were obtained, it w^as realized by all marine engineers that the problem was not yet successfully solved for sea-going vessels operating away from a ready supply of fresh water. What was needed was a burner which would efficiently atomize or spray the oil by pressure alone, or, as it is usually called, mechanical atomization. The Babcock & Wilcox Company had developed an efficient steam- atomizing burner which has been extensively employed with its land boilers, and it then proceeded to develop a mechanical-atomizing burner for use at sea. Such a burner was developed which gave excellent results up to a rate of combustion about equal to Navy forced draft practice with coal, but it was realized that higher rates must be made practicable if the full benefit of oil fuel was to be obtained. Further experimentation made it clear that the burner was equal to any demand, but that the proper admission and admixture of air was of at least equal importance. This led to the invention of an air register or impeller which enabled extremely high rates of combustion to be obtained without smoke and with high efficiency. The burners and registers have now been fitted to a number of naval and merchant steamers where they have given great satisfaction. In November and December, 19 10, a boiler at the Company's w^orks, fitted with these burners and registers, was subjected to a series of tests by a Board of Naval Engineers (which is reprinted in Table XXIII.). In one of these tests the rate of combustion was 1.16 pounds of oil per square foot of heating surface with an evaporation of nearly 16 pounds from and at 212° per square foot of heating surface. The Board stated that this was the highest rate of forcing of which there was any record. (It is equivalent to about 75 pounds of coal per square foot of grate.) In March, 1913, a series of tests was conducted by Lieutenant-Com- mander John J. Hyland, U. S. N., at the Fuel Oil Testing Plant, Philadelphia Navy Yard, on a Babcock & Wilcox boiler which is the same as one of the units supplied for the U. S. S. "Oklahoma" (12 boilers in all). This boiler 63 was specially designed for oil fuel and high rates of forcing, while the one tested in 1910 was designed primarily for coal as fuel. The difference is mainly in the much larger amount of furnace volume in the "Oklahoma's" boilers. On this test, the unprecedented rate of 1.23 pounds of oil and 18.7 pounds of water from and at 212° per square foot of heating surface was obtained. The importance of adequate furnace volume is very great, and this is one of the features in which the Babcock & Wilcox boiler is superior to all others. Indeed this boiler is specially adapted to the use of liquid fuel, and a comparison of its performance with those of other boilers shows a higher efficiency (at least ten per cent.) and a higher capacity. ADVANTAGES OF LIQUID FUEL Among the advantages of liquid fuel for marine boilers may be mentioned : Greater convenience and uniformity of operation. Greatly increased cleanliness. Increased bunker capacity due to greater thermal value. Ability to utilize double-bottom and other spaces not available for £oal. Greatly reduced fire room force. Ease and rapidity of taking fuel on board. Higher efficiency of boiler due to uniform conditions of working, absence of opening doors for firing, and no loss from ashes and unburnt fuel. Absence of the nuisance of ashes and cleaning fires. Elimination of "stand-by" losses. The following table gives the specific gravity and weight of oil corre- sponding to readings on Baumc scale : DENSITY OF OIL Pounds Pounds Degrees Baum^ Specific per Degrees Baumd Specific per Gravity Gallon Gravity Gallon 12 .986 8.22 i 24 •913 7.61 14 •973 8. II 26 .901 751 16 .960 8.00 28 .890 7.42 18 .948 7.90 30 .880 7-33 20 •936 7.80 1 32 .869 7.24 22 .924 7.70 The two following tables are given to show equivalent values of coal and of oil in heat effect and at varying prices. In comparing the heat effect, allowance has been made for the greater efficiency of the boiler when using 64 BABCOCK & WILCOX BOILER. U. S. NAVAL OIL-FUEL TESTIXG-PLAXT. XAVY YARD. PHILADELPHIA. PA. This Boiler Holds the World's Record for Economy and Capacity. Having Evaporated 18.7 Lbs. of Water per Sq. Ft. of Heating Surface per Hour and 15.3 Lbs. of Water per Lb. of Oil (both f. and a. 212° F.) when Burning 1.23 Lbs. of Oil per Sq. Ft. of Heating Surface per Hour. The Boiler Has 4000 .Sq. Ft. of H. S., and Is a Duplicate of Twelve FOR U. S. S. "Oklahoma." 65 oil. Tests on the same boiler at the Babcock & Wilcox works showed that the efficiency with oil is ten per cent, (of the coal efficiency) greater than with coal. The thermal value of the oil has been taken at 19,000 B. T. U., which is an average value for Texas crude. In the second table, com- paring costs, coal of 14,000 B.T. U. (Cumberland or George's Creek) has been used. The density of the oil has been taken at .932 specific gravity (20.7 Baume), which makes the weight of a barrel of 41 gallons, 314 pounds. A ton of coal is taken as 2240 pounds. RELATIVE HEATING EFFECT OF COAL AND OIL Coal, B. T. U. I lb. oil (19,000 B. T. U.) I barrel oil I ton (2240 lbs.) per pound = lbs. coal = lbs. coal coal = bbl. oil 10,000 2.090 656.2 3-41 1 1 ,000 1.900 596.6 3-75 12,000 1.742 546-9 4.09 13,000 1.608 504.8 4-44 14,000 1493 46S.7 4.78 15,000 1-393 437-5 5-12 RF.LATIVE COST OF COAL AND OIL (Coal 14,000 B. T. U.; oil 19,000 B. T. U.) Oil — cents per gallon Oil— dollars per bbl. = Coal — dollars per ton 2.00 $0.82 S3-92 2.25 0.92 4.41 2.50 1.02 4.90 2.75 I-I3 5-39 3.00 1-23 .5-88 3-25 1-33 6.37 3-50 1-43 6.86 4.00 1.64 7.84 4-5(> 1.84 8.82 5.00 2.05 9.80 The chemical composition and the calorific value of oils vary even with samples from the same general locality, so that, in accurate work, it is always necessary to have an analysis made. The following table gives data of some analyses of Texas, California, and Mexican oils. 66 CALORIFIC VALUE, SPECIFIC GRAVITY, ETC., OF FUEL OILS Texas Californian Mexican Report "Oil Fuel" Board Navy Test B. &. W. boiler Report of "Oil Fuel" Board Analysis for n. & W. Co. Carbon % Hydrogen % Sulphur % Oxygen % Calorific Value, B. T. U. . . Specific Gravity Baum6, degrees Moisture % Silt % 84.60 10.90 1.63 2.87 19,060 0.924 22 180° 200° 19,086 0.932 20.7 trace under i 295 295 81.52 II.OI 0.55 6.92 18,667 0.966 15 311 311 I7>55i 0.981 12.8 [ -35 310 347 Flash Point, Fahr Burning Point, Fahr MECHANICAL ATOMIZING BURNER The burner used by The Babcock & Wilcox Company is the in- vention of Mr. E. H. Peabody. He thus describes it in a paper read before The Society of Naval Architects and Marine Engineers, November, 1912: "In the light of our experiments begun in 1907 we have come to believe that the best rotative effect on the oil is produced by the tangential delivery method, and it seems plain that the best way to reduce friction is to reduce the amount of surface to which the oil is exposed in its travel through the burner after it begins to whirl and until its exit from the tip. We have also come to attach great importance to simplicity in everything connected with oil burning and believe that the oil burner itself should be of simple construction, easily taken apart, and so designed that when taken apart all the small passages and wearing surfaces will be exposed for inspection, cleaning, and repair. " The results of the writer's efforts to construct a burner to meet these requirements are shown in the cut on p. 69. Oil is delivered under pressure to an annular channel cut into the face of a nozzle upon which is screwed a tip having a very small central chamber communicating with a discharge orifice. Between the nozzle and the tip a thin washer or disc is inserted and held firmly in place. This has a hole in the center corresponding with the diameter of the central chamber of the tip, and small slots or ducts, extending tangentially from the edges of the central opening outward toward the periphery of the washer, long enough to overlap the annular channel of the nozzle and put it in communica- tion with the central chamber. The effect is that, when the burner is assembled with the washer in place, oil is delivered through the ducts tangentially to the central chamber where it rapidly revolves and almost immediately is discharged through the orifice in the tip. " In order to correct a popular fallacy I beg to call attention here to the fact that no mechanical atomizer produces a revolving spray, but the particles of oil fly off in straight lines under the influence of centrifugal force, thus forming 67 a hollow, conical spray. The fineness of this spray, /. e., the minuteness of the particles forming it, has a most important bearing on the results obtained in the furnace. It is possible with some forms of steam atomizers to atomize oil so finely that no flame at all will be produced, the incandescent combustion chamber being filled with a clear invisible gas and every brick being discernible. I doubt if this condition of flameless combustion can be produced with mechanical ato- mizers and heavy oil, nor is it desirable under any circumstances for the simple reason that it costs too much. "With the production of flame, however, furnace design assumes an added importance, for the flame must be distributed evenly and without localizing on the heating surface of the boiler, and the gases must be given time and space in which to expand and burn as nearly as possible to completion before being cooled and the flame extinguished b}' contact with the tubes of the boiler. These points become exceedingly vital when the boiler is forced to the requirements now demanded in naval service." AIR REGISTER OR IMPELLER This device for regulating and directing the admission of air, and referred to on page 63, is the invention of Alcssrs. Peabody and Irish, and reference is made to it in the paper of Mr. Peabody, just quoted, as follows: "Great delicacy is required in introducing the air for combustion, very slight changes affecting the results in unsuspected ways, and while almost any method may result in smokeless combustion, maximum economy and capacity can be secured only by careful and intelligent design. "It is not necessary to give the air a whirling motion but, judging from our rather exhaustive experiments, better gas anah'ses are secured, lower air pressures are required, and less refinement of adjustment is needed if the air is brought into contact with the oil spray with the right sort of a twist. We have found the impeller plate, illustrated on this page, most effective in accomplishing this mixture, and our most satisfactory results have been obtained with it." Impeller or Air Register — Patented 68 Q W H H P< o CO H 69 EFFICIENCY— USE OF THE COAL CALORIMETER THE term "efficiency," specifically applied to a steam boiler, re- fers to the proportional amount of heat which is taken from the available supply in the fuel and transferred to the steam generated. In the case of an engine, the efficiency is deter- mined by the amount of heat taken from the steam and transformed into useful work. The efficiency of an entire plant, which includes both engine and boiler and all auxiliary machinery, embodying all their combined efficien- cies, appears as the amount of work which can be developed by the engine for each unit of fuel consumed in the furnaces. It is evident, therefore, that if a poor engine be installed, the efficiency of the plant as a whole will be low, notwithstanding a highly efficient boiler, and vice versa; and the same thing will also be true, even with a first-class engine and boiler, provided much heat is wasted in the auxiliary machinery. A statement of the efficiency of a plant, therefore, indicates but little, unless something is known of its general design and the type of its various parts. Efficiency is best expressed as a percentage of the total heat supplied. Enough is known of the properties of the steam itself to make the calculation of engine efficiency an easy matter in connection with a careful test. In the case of the boiler, however, as the available heat is in the coal, the proposition is of an entirely different character, and a separate test, in addition to that of the boiler, becomes necessary in order to determine the amount of heat that has been supplied by the combustion of the fuel. In fact, so difficult has this accurate determination of the heat value of coal been found, that engineers with any desire to avoid setting up false standards have until recently considered it best to make no report whatever on this point rather than to put forth unreliable or doubtful figures. Still, without a determination of efficiency, we are left to flounder in a sea of ignorance where the only things that keep afloat our desires for comparison are cut and dried assumptions that nine times out of ten have no counterpart in fact. What right have we to assume that the Ohio coal, or Western Pennsyl- vania slack, burned under the boilers of the large ore-carrying vessels of the Great Lakes, is the same as or equivalent to the Welsh or the Cumber- land coal used by the transatlantic flyers? And yet, that is exactly what we do when we compare the i .6 pounds of coal per indicated horse-power of the transatlantic service with the 1.8 pounds of the Lake practice, to the disparagement of the latter. As a matter of fact, the best ships of that remarkable fleet of grain and ore carriers on the Lakes equal or even exceed in the matter of efficiency the larger units of the ocean greyhounds. But, it is only by the aid of a reliable coal calorimeter that we are able to recognize such facts as these, and to realize that, without such data, terms like ''coal burned per indicated horse-power,'' and "water evaporated per pound of coal" mean practically nothing when used as a basis for comparison. The method of determining the heat value of fuel that at once ap- pealed to pioneers in this work, was the burning of a sample of the fuel in a vessel surrounded by water, and, by measuring the rise in tempera- ture of the water, estimate the heat units evolved during the combustion. The two principal sources of error encountered were: incomplete combustion, and the liability of some of the products of combustion to escape without giving up all their heat to the water. These two objec- tions prevail to-day in many forms of coal calorimeters, and, added to the fact that oftentimes insufficient precaution is taken to calculate radiation losses, serve to promulgate reports of very low calorific values for coal and very high percentages of boiler efficiency. The form of calorimeter best adapted to overcome these difficulties is that designed by M. Berthelot, in which the combustion takes place in an atmosphere of oxygen gas tightly enclosed in a metal bomb which is it- self submerged in water of known weight. The sample of coal to be tested (the calorimeter is equally adapted to liquid or to gaseous fuels) is finely powdered, weighed, and suspended, in the center of the bomb, in a small platinum dish or pan; the cover of the bomb is then screwed on and oxygen gas pumped in through a valve at the top, a pressure of 20 to 25 atmospheres being used to insure a large excess of oxygen when the combustion takes place. The bomb is then placed in the water, which is constantly stirred, until the whole apparatus comes to the same temperature, and enough readings are taken from the thermometer placed in the water to establish the rate of radiation under the conditions existing before combustion. It is well to have the water at the same temperature as the room, or slightly above. When all is ready to start the combustion, an electric current is passed through a very fine iron wire which has previously been sus- pended from terminals inside the bomb in such a way as to touch the coal. On the passage of the current, the wire instantly fuses and ignites the coal, which, owing to the atmosphere of oxygen, burns rapidly and com- pletely, giving up its heat to the walls of the bomb, which in turn give it up to the water. The rise in temperature of the water is carefully noted, the observations being continued until after the whole comes to the same temperature and begins to cool, and the rate of cooling is established. The thermometer used is graduated in fiftieths of a degree centigrade, and can be read to one-half of a hundredth of a degree. In this way the loss by radiation during the combustion may readily be determined and the 71 proper allowance made. The combustion is always complete, and no loss of heat occurs from escaping gases, for the reason that the gases do not escape until after the whole operation is finished and the bomb is opened. The bomb calorimeter, as designed by Berthelot, however, is exceed- ingly expensive, and it remained for M. Mahler to redesign this instrument, replacing the interior shell of platinum by a coating of enamel and other- wise improving and cheapening the construction so that the bomb calo- rimeter in its new form was brought within reach of the industrial world. The accompanying cut shows the Mahler apparatus in all its essential details. The mode of operation is identical with that explained above, and all the advantages claimed for the Berthelot bomb are true of the Mahler. Notwithstanding the fact that the Mahler calorimeter is far more expensive than many other types, the principle of its operation and the facility with which it can be made to give trustworthy determinations of the heating value of fuels, led to its selection as the best instrument for this work by the committee of the American Society of Mechanical Engineers, which drew up the 1 899 code relative to a standard method of conducting steam boiler trials. It therefore stands as the representative coal calo- rimeter of the day. CALORIMETER OF M. PIERRE MAHLER FOR DETERMIXIKG THE HEATING VALUE OF FUELS Explanation: A — Water jacket to diminish radiation. B — Steel bomb. lined with enamel. C — Platinum pan for coal. D — Calorimeter containing weighed water. E — Electrode. F — Fuse wire. G — Support for agitator and thermometer. K — Spring and screw for revolving agitator. L — Lever of agitator. M — Pressure gauge. O — Oxygen cylinder. P — Electric battery. S — Agitator. T — Thermometer. 72 NOTES ON THE ANALYSIS OF CHIMNEY GASES BY THE -ORSAT" APPARATUS T HE principal constituents of the gases in the flues or chimney of a boiler are as follows: Symbol 1. Oxygen O 2. Nitrogen N 3. Carbon dioxide, usually called carbonic acid gas .... CO2 4. Carbonic oxide CO The object of the analysis is to determine the percentage of these gases present, and to deduce therefrom the amount of air actually entering the furnace, as compared with the air theoretically necessary for combustion. If all the air admitted to the furnace could be brought into such intimate r^ Chimney Orsat Apparatus for Gas Analysis contact with the fuel that every atom of the oxygen contained in it could be utilized for the purposes of combustion, the escaping gases would practi- cally consist of only carbonic acid and nitrogen — that is, each atom of the carbon of the fuel w^ould unite with two atoms of oxygen in the air admitted, forming CO 2, the nitrogen passing through unchanged. Such a result is, however, unattainable, and unless an excess of air be admitted, the carbon will not be completely consumed, and CO, consisting of one atom of carbon combined with one atom of oxygen, will be formed, instead of CO 2. The 73 < i^ o O u 74 formation of CO results in a very serious loss of heat, and must therefore be prevented by admitting some excess of air. The excess of oxygen required is generally from 6 to 8 per cent, of the volume of the gases. If there is less than 6 per cent, of oxygen there will almost certainly be traces of CO. The Orsat apparatus enables the percentages of oxygen, carbon dioxide, and carbonic oxide to be ascertained directly. The remainder is usually considered to be nitrogen, as, although there are traces of other gases, they are insignificant. The apparatus, which is shown on page 73, consists essentially of a measuring tube A, into which a sample of the gas is drawn, and of three other vessels B, Bi,and B2, which contain substances capable of absorbing respectively, carbon dioxide, oxygen, and carbonic oxide. The method of using the apparatus is as follows: Through a suitable hole in the chimney, uptake, or flue, insert a piece of iron tube, long enough to reach well past the center, the tube having saw slits in its circumferential plane for a length of 12 inches or more. If desired, a tube perforated with small holes may be used instead. See that the aperture in the chimney, round the tube, is tightly plugged, so as to prevent air (which w^ould probably vitiate the results obtained) being drawn in. Place the apparatus in a convenient position near the chimney, the bottom of the apparatus being, say, about 3 feet above the level of the feet of the observer; connect the end of the iron tube to the apparatus by an india-rubber pipe D, having a U-tube filled with glass wool inserted at the position marked E, between the apparatus and the boiler, so as to intercept dust. The bottle C is to be filled about two-thirds full of water, and con- nected to the bottom of the measuring tube A by an india-rubber tube. When this bottle is placed on the top of the case containing the apparatus, or at some other convenient similar height, the water will naturally flow into the vessel A. If now the bottle C be placed below the apparatus and the cock a opened, it is evident that as the water flows out of A the gas will be drawn in from the flue and take its place. Draw in the gas well below the zero mark, and cut off the connection wdth the flue by closing the cock a. Then lift the bottle C, so that the water level in it coincides with the zero mark in the measuring tube, and open the three-way cock a to the atmos- phere to allow of the surplus gas escaping. We thus obtain the tube A full of gas at atmospheric pressure. Again close the cock a. Then, by opening one of the cocks, b, bi, or 62, the gas contained in the measuring tube A can be forced into either of the vessels B, Bi, or B2, by raising the bottle C so that the water flows into A, due care being taken that the water never 75 rises above the mark at the top of the measuring tube. The vessels B, Bi, and B2 contain the following reagents: Vessel. Reagent. To absorb. B One part commercial caustic potash and two parts of water (solution of Sp. Gr. 1.2) CO2 Bi. Five grammes pyrogallic acid dissolved in 15 cc. water. 120 grammes caustic potash dissolved in 80 cc. water. The two solutions to be mixed O B2. Saturated solution cuprous chloride in hydrochloric acid . . . CO These absorbing vessels should be filled with the reagents, rather more than half-way up. It is essential that the gases to be tested be passed through the different reagents in the order given above, otherwise incorrect results will be obtained. The vessels B, Bi, and B2 contain small glass tubes. These are used with the object of giving a greater wetted surface to absorb the gas introduced. The tubes with copper wire round them are for the vessel B2 containing cuprous chloride. Note. — Care should be taken to kecj:) the pyrogallic solution from air, as it absorbs oxygen rapidly. It is best to mix the potash solution with it in the tube. The measuring tube A is, for convenience of calculation, marked off into 100 parts, so that percentages may be read off easily. At the moment of measuring the volume of gas in the graduated tube, the water bottle must be held at such a height that the level of the water in it is exactly the same as in the graduated tube, otherwise the gas will be compressed or expanded by the difference between the two columns of water. Before commencing the test get rid of as much as possible of the air in the tubes by using the small hand-bellows shown in figure ; then draw several samples of the gas into the measuring tube, and discharge each in its turn to the atmosphere through the three-way cock a. Having obtained an un- diluted sample, shut the cock a, open the cock b, and force the gas into the vessel B. Draw the gas back into the vessel A, and repeat the operation three or four times, so as to ensure the thorough absorption of the CO 2. The last two readings should give the same result, showing that the absorption is complete. Follow the same procedure with the remaining two vessels Bi and B2, taking the reading of the reduced quantity of gas in the vessel A after each operation. CO 2 is absorbed by the caustic potash solution very quickly, and it will be found that passing the gas three times through the absorbing vessel B will generally be quite sufficient. The gas, however, must be passed through the pyrogallic solution at least five or six times, in order that 76 the oxygen may be all absorbed. If this be not done, the oxygen remaining will be absorbed by the cuprous chloride, and will be mistaken for CO, although there may be none of that gas present. The total of the percentages of the three gases CO 2, CO, and O, should be about 19.5, and this rule may be used as a rough check on the analysis. As the percentage by volume of oxygen in air is 21, the volume of air corresponding with any given volume of oxygen may be found by multiply- ing by ^^, or 4.762. The volume of air corresponding to a given volume of CO 2 may also be found by multiplying by the same figures. EXAMPLE:— Analysis shows. Then air used for combustion And excess air 13-5 6% CO3 O 13.5 X 4.762 = 64.3 = 6 X 4.762 = 28.6 92.9 The percentage of excess air above that which is necessary for combustion is therefore: 100 X 28.6 64-3 •=44-5% Care should be taken with regard to the following points: 1. The absorbent should not be forced below the point D, or some of the gas may escape and be lost, and, of course, an incorrect result obtained. 2. The absorbent must be at exactly the same level in the tube — say at C, when measuring the volume after the gas has been absorbed as before. 3. Time must be allowed for the water to drain down the sides of the tube before taking a reading. The time must be the same on each occasion, otherwise more water will drain down at one time than another, and an incorrect reading result. A 3500-MILE R.\iL Shipment for the Pacific Coast REASONS FOR HIGH EFFICIENCY OF BOILERS THE text-books on physics explain that fluids are heated (and cooled) not by direct conduction of heat, but by what is called convection, where the portion near the source of heat has its temperature raised and is displaced by the cooler portions which are heated in turn. It is evident, therefore (as already referred to on page 29), that the boiler which provides most thoroughly definite paths for the hot gases and the water and, at the same time, breaks them up so that all portions can intermingle, will abstract the greatest percentage of heat and thus give the highest efficiency. The Babcock & Wilcox boiler accomplishes this in the most thorough manner. By means of the fire-brick roof and the increasing volume of the furnace, the fuel is given ample opportunity for complete combustion before the hot gases pass among the tubes. By means of the vertical baffles, the gases are directed at right angles across the tubes three times; and, in addition, owing to the sinuous headers which "stagger" the tubes, the gases are thoroughly broken up and every part brought in contact with the heating surface. From the top of the last pass, the gases go direct to the smoke pipe, with a minimum loss of draft. It will be seen, therefore, that the circulation of the gases is perfect. The water is fed into the steam and water drum and thence descends through the connecting nipples to the front headers, from which it jDasses through the tubes receiving heat and being partly converted into steam. The mixed steam and water fills the back headers and passes through the return circulating tubes to the steam and water drum, separating so that the water falls into the body of water in the drum, while the steam passes around the ends of the baffle-plate into the steam space. It is hard to conceive of a simpler and more direct circulation. Inasmuch as boilers have been constiuctcd with tubes at every in- clination from horizontal to vertical, the query would naturally arise whetlicr one inclination is better than another. This subject has been investigated by special tests and confirmed in practice, showing that maximum results are secured when the tubes have an inclination of 10 degrees to 15 degrees to the horizontal. The standard angle for the Babcock & Wilcox boiler is 15 degrees. The increased rates of combustion with coal and the use of oil fuel, with its possibilities of very high forcing, have raised the question of the effect of this greatly stimulated evaporation on the circulation, that is, whether it will be as definite as at lower rates but simply increased in amount. This has been the subject of careful laboratory investigation and also of extended tests of boilers under all degrees of forcing. These have all shown conclusively that, in a well-designed boiler with a simple 78 and definite path for the circulation, there will be no change of direction however severe the forcing. It is very clear, therefore, that, in the Babcock & Wilcox boiler, the conditions are almost ideal for a perfect circulation, and experience has shown this to be the fact. In the tests of the "Wyoming's" boiler with oil fuel, the unprecedented rate of evaporation of almost i6 pounds per square foot of heating surface was maintained without any difficulty, and subse- quent examination showed that no part of the boiler had been injured or distorted in the least degree. Without perfect circulation, such a per- formance is impossible. December on Lake Superior 79 STEAM— PROPERTIES AND LAWS OF GENERATION WHEN water is converted into steam it has first to be heated to a certain definite temperature which is called the boiling point. This temperature equals 212 degrees Fahrenheit for the or- dinary pressure of the atmosphere (14.7 pounds above vacuum), but as the pressure is increased the boiling point increases, although at a decreasing ratio, until at 500 pounds above vacuum it equals 467.3 degrees Fahrenheit. As the water rises in temperature, it absorbs heat at the rate of one B. T. U. for each degree Fahrenheit. This is known as the heat of the liquid, or sensible heat, as it may be shown by means of a thermometer. After reaching the boiling point, the further addition of heat transforms the water into steam without increasing its temperature. The heat thus absorbed is called the heat of vaporization, or "latent heat," and cannot be shown by any instrument for measuring temperatures. The latent heat decreases as the pressure increases, it being about 970 British thermal units per pound at atmospheric pressure, and about 762 at 500 pounds pressure above vacuum. It will be seen, therefore, that the temperature of steam normal to its pressure, is the same as of the water at the boiling point, and also that the total heat in steam consists of two parts; first, the heat contained in the liquid at the boiling point, and second, the heat of vaporization. Or, in other words, the total heat is the sum of the sensible heat and the latent heat. The total heat increases slightly as the pressure increases, being 1 150.4 British thermal units per pound at atmospheric pressure, and 12 10 Britisli thermal units at 500 pounds. The density of steam increases with the pressure, and varies as the 17th root of the i6th power. Its weight per cubic foot may be found by the formula w = .003027/?'^', where p = the pressure above vacuum. The re- sults are correct within y, per cent, up to 250 pounds pressure. Saturated steam cannot be cooled except by lowering its pressure, any cooling effect being compensated for by some of the steam being con- densed and giving up its latent heat. Neither can steam in direct contact with water be heated above the normal temperature corresponding to its pressure, providing there is an opi)ortunity for free transference of heat; the only effect of the addition of more heat being to evajDorate more water. If there is no outlet for the additional steam formed, both the pressure and the temperature will be increased. When steam is removed from contact with water, it may be heated above the normal temperature corresponding to its pressure. It is then called superheated. The table on page 8 1 gives the properties of saturated steam at various pressures. 80 PROPERTIES OF SATURATED STEAM (Compiled from Wm. Kents' condensation of Marks & Davis's Tables) 3 Q-ui 3 3 -::1 .S 'I' '3 i ^ ill 0 ci < 14.7 212.6 180.0 970.4 5-3 20.0 228.0 196. 1 960.0 10.3 25.0 240.1 208.4 952.0 15-3 30.0 250.3 218.8 945-1 20.3 35-0 259.3 227.9 938.9 25-3 40.0 267.3 236.1 933.3 30.3 45-0 274.5 243.4 928.2 35.3 50.0 281.0 250.1 923.5 40.3 55-0 287.1 256.3 919-0 45-3 60.0 292.7 262.1 914-9 50.3 65.0 298.0 267.5 91 1.O 55-3 70.0 302.9 272.6 907.2 60.3 75-0 307.6 277.4 903.7 6S.3 80.0 312.0 282.0 900.3 70.3 85.0 316.3 286.3 897.1 75-3 90.0 320.3 290.5 893-9 80.3 95-0 324.1 294.5 890.9 85.3 100. 327.8 298.3 888.0 90.3 105.0 331.3 302.0 885.3 95-3 IIO.O 334.8 305. 5 882. 5 100.3 115-0 338.0 308.9 879.9 105.3 120.0 341.3 312.3 877.2 no. 3 125.0 344.4 315.5 874.7 115. 3 130.0 347.4 318.6 872-3 120.3 135.0 350.2 321.7 869.9 I2S-3 140.0 353.1 324.6 867-6 130.3 145-0 355.8 327.4 865-4 135-3 150.0 358.5 330.2 863.2 140.3 155-0 361.0 332.9 861.0 145.3 160.0 363.6 335.6 858.8 150.3 165.0 366.1 338.2 856.8 155-3 170.0 368.S 340.7 854.7 157-3 172.0 369.4 341.7 853-9 159-3 174.0 370.4 342.7 8S3-I 161. 3 176.0 371.3 343.7 852.3 163.3 178.0 372.2 344.7 851.5 165.3 180.0 373.1 345.6 850.8 167.3 182.0 374.0 346.6 850.0 169.3 184.0 374-9 347.6 849.2 171.3 186.0 375-8 348.5 848.4 173-3 188.0 376.7 349.4 847.7 175-3 190.0 377.6 350.4 846.9 177-3 192.0 378. 5 351.3 846.1 179.3 194.0 379.3 352.2 845.4 181. 3 196.0 380.2 353.1 844-7 183-3 198.0 381.0 354.0 843-9 185.3 200.0 381.9 354.9 843-20 187.3 202.0 382.7 355.8 842.48 189.3 204.0 383.6 356.7 841.76 191. 3 206.0 384.4 357-5 841.04 193.3 208.0 385.2 358-4 840.32 195.3 210.0 386.0 359.2 839.60 197-3 212.0 386.8 360.1 838.92 199.3 214.0 387.6 361.0 838.24 201.3 216.0 388.3 361.8 837.56 203.3 218.0 389.1 362.6 836.88 205.3 220.0 389.9 363.4 836.20 207.3 222.0 390.7 364.3 835.52 <" a ^ 150.4 156.2 160.4 163.9 166.8 169.4 171. 6 173.6 175.4 177.0 178.5 179-8 181. 1 182.3 183.4 184.4 185.4 186.3 187.2 188.0 188.8 189.6 190.3 191. 191. 6 192.2 192.8 193.4 193-9 194-5 195.0 195.4 195.6 195.8 196.0 196.2 196.4 rg6.6 196.8 196.9 197. 1 197.3 197.4 197.6 197.8 197.9 198.10 198.24 198.38 198.52 198.66 198.80 198.96 199.12 199.28 199.44 199.60 199.72 x; o M r'3 a 0.03732 0.04980 0.06140 0.0728 0.0841 0.0953 0.1065 0.II7S 0.128S 0.1394 0.1503 0.1612 0.1721 0.1829 0.1937 0.2044 0.2151 0.2258 0.236s 0.2472 0.2578 0.2683 0.2790 0.2897 0.3002 0.3107 0.3213 0.3320 0.3425 0.3529 0.3633 0.3738 0.3780 0.3822 0.3864 0.3906 0.3948 0.3989 0.4031 0.4073 0.411S 0.4157 0.4199 0.4241 0.4283 0.432s 0.4370 0.4410 0.4450 0.4490 0.4530 0.4570 0.4612 0.4654 0.4696 0.4738 0.4780 0.4S22 3 Oi , O S 209.3 2H.3 213.3 215.3 217.3 219.3 221.3 223.3 225.3 227.3 229.3 231.3 233.3 235-3 237-3 239.3 241.3 243.3 245.3 247.3 249-3 251-3 253-3 255.3 257.3 259.3 261.3 263.3 265.3 267.3 269.3 271.3 273.3 275-3 277.3 279.3 281.3 283.3 285.3 287.3 289.3 291.3 293.3 295.3 297.3 299.3 301.3 303.3 305.3 315.3 325.3 335.3 360.3 385.3 410.3 435-3 460.3 485.3 224.0 226.0 228.0 230.0 232.0 234.0 236.0 238.0 240.0 242.0 244.0 246.0 248.0 250.0 252.0 254.0 256.0 258.0 260.0 262.0 264.0 266.0 268.0 270.0 272.0 274.0 276.0 278.0 280.0 282.0 284.0 286.0 288.0 290.0 292.0 294.0 296.0 298.0 300.0 302.0 304.0 306.0 308.0 310.0 312.0 314.0 316.0 318.0 320.0 330.0 340.0 350.0 375.0 400.0 425.0 450.0 475.0 500.0 .E ■? 'C 3 m'oj -S-c rt ^ rt Ji-^ ■--2 S E 9 S p,^Ji ^^•^ c^'% Ba-% ^^^ - (X. 391.5 365.1 834.84 392.3 365.9 834.16 393.1 366.7 833.48 393.8 367. 5 832.80 394.5 368.3 832.14 395.3 369.1 S3 1. 48 396.0 369.8 830.82 396.7 370.6 830.16 397.4 371.4 829.50 398.2 372.1 828.86 399.0 372.9 828.22 399.7 373.6 827.58 400.4 374.4 826.94 401. 1 375.2 826.30 401.8 376.0 825.66 402.4 376.7 825.02 403.1 377.5 824.38 403.8 378.2 823.74 404.5 378.9 823.10 405.2 379.6 822.50 405.9 380.4 821.90 406.6 381. 1 821.30 407.2 381.8 830.70 407.9 382.5 820.10 408.6 383.2 819.50 409.2 383.9 818.90 409.9 384.6 81S.30 410.5 385.3 817.70 411. 2 386.0 817.10 411. 8 386.7 816.52 412.4 387.4 815-94 413. 1 388.1 815-36 413.7 388.7 814.78 414.4 389.4 814.20 415.0 390.1 813-62 415.6 390.8 813.04 416.2 391.4 812.46 416.8 392.1 811.88 417. 5 392.7 811.30 418. 1 303.3 810.74 418.7 ^.4-0 810.18 419.3 394.6 809.62 419.9 395.3 809-06 420.5 395.9 808.50 421. 1 396.5 807.96 421.7 397.2 807.42 422.2 397.8 806.88 422.8 398.5 806.34 423.4 399.1 805.80 426.3 402.2 803.10 429.1 405.3 800.40 431.9 408.2 797. So 438.5 415.4 791.55 444-8 422.0 786.00 450.8 428.5 779.00 456.5 435-0 774.00 461.0 441-5 768.00 467.3 448.0 762.00 x'il 199.84 199.96 200.08 200.20 200.34 200.48 200.62 200.76 200. go 201.02 201.14 201.26 201.38 201.50 201.62 201.74 201.86 201.98 202.10 202.20 202.30 202.40 202.50 202.60 202.70 202.80 202.90 203.00 203.10 203.20 203.30 203.40 203.50 203.60 203.70 203.80 203.90 204.00 204.10 204.18 204.26 204.34 204.42 204.50 204.58 204.66 204.74 204.82 204.90 205.30 205.70 206.10 206.95 208.00 208.00 209.00 209.00 210.00 e:fc o Sr''. B 0.4864 0.4906 0.4948 0.4990 0.5032 0.5074 0.5116 0.5158 0.5200 0.5242 0.5284 0.5326 0.5378 0.5410 0.5450 0.5490 0.5530 0.5570 0.5610 0.5652 0.5694 0.5736 0.5778 0.5820 0.5862 0.5904 0.5946 0.5988 0.6030 0.6072 0.61 14 0.6156 0.6198 0.6240 0.6282 0.6324 0.6366 0.6408 0.6450 0.6492 0.6534 0.6576 0.6618 0.6660 0.6702 0.6744 0.6786 0.6828 0.6870 0.7080 0.7290 0.7500 0.801S 0.8600 0.9100 0.9600 1.0200 1.0800 Pressures below the atmosphere, or partial vacuum, are often expressed in inches (of mercury). The following table gives the temperature and pressure of steam corresponding to various vacua. a; H w u; ( u 82 PROPERTIES OF SATURATED STEAM BELOW ATMOSPHERIC PRESSURE Vacuum in Absolute Temperature Heat of Liquid Latent Heat Total Heat Density inches of Pressure Degrees above 32° F. above 32° F. above 32° F. Weight of a Cubic Mercury Pounds Fahr. B.T.U. B.T.U. B.T.U. foot — Pounds 29-5 0.207 54-1 22.18 1 061.0 1083.2 0.000678 29.0 0.452 76.6 44.64 1048.7 1093-3 O.OOI415 28.5 0.698 90.1 58.09 1 04 1 . 1 1099.2 0.002137 28.0 0.944 99-9 67.87 1035-6 1 103-5 0.002843 27.0 1.44 112.5 80.4 1028.6 1 109.0 0.00421 26.0 1-93 124-5 92-3 1022.0 III4.3 0.00577 25.0 2.42 132.6 100.5 IOI7.3 III7.8 0.00689 24.0 2.91 1 40. 1 108.0 IOI3.I II2I.I 0.00821 22.0 3-89 151-7 II9.6 1006.4 I 126.0 0.01078 20.0 4.87 161. 1 128.9 lOOI.O 1 129.9 O.OI33I 18.0 =5.86 168.9 136.8 996.4 I 133-2 O.OI58I 16.0 6.84 175-8 143.6 992.4 1 136.0 0.01827 14.0 7.82 181.8 149.7 988.8 II38.5 0.02070 12.0 8.80 187.2 1 55- 1 985.6 1 140.7 0.02312 lO.O 9-79 192.2 160. 1 982.6 1 142.7 0.02554 5-0 12.24 202.9 170.8 976.0 1 146.8 0.03148 WEIGHT OF WATER AT TEMPERATURES ABOVE 200° FAHR. (Landolt's and Bornstein's Tables, 1905) Deg. Lbs. per Deg. Lbs. per Deg. Lbs. per Deg. Lbs. per F. Cu. Ft. F. Cu. Ft. F. Cu. Ft. F. Cu. Ft. 200 60.12 300 57-33 400 53-5 500 48.7 210 59.88 310 57.00 410 53-0 510 48.1 220 59-63 320 56.66 420 52-6 520 47.6 230 59-37 330 56.30 430 52.2 530 47.0 240 59-11 340 55-94 440 51-7 540 46-3 250 58-83 350 55-57 450 51.2 550 45-6 260 58-55 360 55-18 460 50.7 560 44-9 270 58.26 370 54-78 470 50.2 570 44.1 280 57-96 380 54-36 480 49-7 580 43-3 290 57-65 390 53-94 490 49-2 590 600 42.6 41.8 WATER— THE MEASUREMENT OF HEAT Water has a greater capacity for absorbing heat than any other known substance — bromine and hydrogen excepted. For this reason and from the fact that it is so commonly found in nature, and can be easily handled in experimental work, it has been adopted as the standard substance for measuring the quantity of heat. Two distinct heat units are used in practice — calories and British thermal units. The latter, usually designated by the letters B. T. U., is the quantity of heat required to raise the temperature of one pound of water one degree Fahrenheit. The calorie is the quantity required to raise a kilogram of water one degree centigrade, and is equal to 3.958 British thermal units. The heat-absorbing capacity, or, as it is called, the specific heat of 83 ►J - 5 o - a 84 water, is not exactly constant for all temperatures, but after decreasing very slightly, again increases, and in a gradually increasing ratio, as the temperature is increased. The accompanying table shows the number of British thermal units that will be absorbed by one pound of water, when heated from 32 degrees to various temperatures below 212 degrees. WATER BETWEEN 32 AND 212 DEGREES FAHRENHEIT Tem- Heat Weight. Tem- Heat Weight, Tem- Heat Weight, Tem- Heat Weight, pera- Units Pounds pera- Units Pounds pera- Units Pounds pera- Units Pounds ture above 32° per ture above 32° per ture above 32° per ture above 3 2° per Fahr. per Lb. Cub. Ft. 1 Fahr. per Lb. Cub. Ft. Fahr. per Lb. Cub. Ft. Fahr. per Lb. Cub. Ft. 32 0.00 62.42 78 46.04 62.24 124 91.90 61.65 170 137-87 60.80 34 2.01 62.42 80 48.03 62.22 126 93 90 61.61 172 139-87 60.76 36 4-03 62.43 82 50.03 62.20 128 95 89 61.58 174 141.87 60.71 38 6.04 62.43 84 52.02 62.18 130 97 89 61-55 176 143-87 60.67 40 8.05 62.43 86 54.01 62.16 132 99 88 61.52 178 145-88 60.62 42 10.06 62.43 88 56.01 62.14 134 lOI 88 61.49 180 147.88 60.58 44 12.06 62.43 90 58.00 62.12 136 103 88 61.45 182 149.89 60.53 46 14.07 62.42 92 60.00 62.09 138 105 87 61.41 184 151.89 60.49 48 16.07 62.42 94 61.99 62.07 140 107 87 61.38 186 153-89 60.45 50 18.08 62.42 96 63.98 62.05 142 109 87 61.34 188 155-90 60.40 52 20.08 62.41 98 65.98 62.03 144 III 87 61.31 190 157-91 60.36 54 22.08 62.40 100 67.97 62.00 146 113 86 61.27 192 159-91 60.31 56 24.08 62.39 102 69.96 61.98 148 115 86 61.24 194 161.92 60.27 58 26.08 62.38 104 71.96 61-95 150 117 86 61.20 196 163.92 60.22 60 28.08 62.37 106 73-95 61.93 152 119 86 61.16 198 165-93 60.17 62 30.08 62.36 108 75-95 61.90 154 121 86 61.12 200 167.94 60.12 64 32.07 62.35 no 77-94 61.86 156 ^ 123 86 61.08 202 169.95 60.07 66 34-07 62.33 112 79-93 61.83 158 125 86 61.04 204 171.96 60.02 68 36.07 62.32 114 81.93 61.80 160 127 86 61.00 206 173-97 59-98 70 38.06 62.30 116 83.92 61.77 162 129 86 60.96 208 175-98 59-93 72 40.05 62.29 118 85.92 61.74 164 131 86 60.92 210 177-99 59.88 74 42.05 62.27 1 120 87.91 61.71 166 133 86 60.88 212 180.00 59-83 76 44.04 62.26 1 ^22 89.91 61.68 168 135 86 60.84 There are four notable temperatures for pure water, viz. : 1. Freezing point at sea level, 32° F. . . . Weight per cii. ft., 62.418 lb.; per cu. in., .03612 lb. 2. Point of maximum density, 39.1° F. . . Weight per cu. ft., 62.425 lb.; per cu. in., .036125 lb. 3. British standard for specific gravity, 62° F. Weight per cu. ft., 62.355 lb-! per cu. in., .03608 lb. 4. Boiling point at sea level, 212° F. . . . Weight per cu. ft., 59.830 lb.; per cu. in., .03462 lb. A United States standard gallon holds 231 cubic inches, and 8.3356 pounds of water at 62 degrees Fahrenheit. A British imperial gallon holds 2'j'j.2'j^ cubic inches, and 10 pounds of water at 62 degrees Fahrenheit. Sea water (average) has a specific gravity of 1.028, boils at 213.2 degrees F., and weighs 64 pounds per cubic foot at 62 degrees Fahrenheit. A pressure of i pound per square inch is exerted by a column of water 2.3094 feet, or 27.71 inches high, at 62 degrees Fahrenheit. 85 EQUIVALENT EVAPORATION FROM AND AT 212° F. FOR purposes of comparison, it is usual to reduce the actual evapora- tive results obtained in practice, to a common standard, known as ^^ equivalent evaporation from and at 212 T This means that the temperature of the feed water is supposed to be at 212 degrees, and that the evaporation takes place at atmospheric pressure, or jrom 212 degrees, the equivalent amount of water being calculated which would be evaporated under such conditions. In both cases the heat imparted to the water is the same, and in order to find the "equivalent evaporation," it is only necessary to find the amount of heat actually absorbed by the water in being converted into steam in the boiler, and divide this by 970.4, the latent heat of steam at atmospheric pressure, which is the heat required to evaporate one pound of water "from and at 212 degrees." For example, suppose that 3000 pounds of water are evaporated per hour at a pressure of 70 pounds, the feed water entering the boiler at 100 degrees Fahrenheit. By reference to the steam tables, it is found that steam at 70 pounds gauge jjressure (84.7 absolute) contains 1183.34 British thermal units per pound above 32 degrees ; and from the table for heat in the water, it is found that each pound of water at 100 degrees Fahrenheit con- tains 67.97 British thermal units above 32 degrees. The boiler will there- fore have to impart to each pound of steam generated, the difference between these quantities, or (i 183.34 - 67.97) 1 1 15.37 British thermal units. This amount, divided by 970.4, gives 1.1493, or, say, 1.15. That is, the same amount of heat imparted to one pound of water at 100 degrees Fahrenheit, in converting it into steam at 70 pounds pressure, would evaporate 1.15 pounds from and at 212 degrees Fahrenheit; so that 3000 pounds evaporated at actual conditions are equivalent to (1.15 X 3000) 3450 pounds from and at 212 degrees. The quantity 1.15 is called the factor of evaporation. It may be expressed by the following formula: F = , in which // equals the total heat in steam above 32 degrees at boiler pressure; h equals the heat in the feed water above 32 degrees, and 970.4 equals the latent heat in steam at atmospheric pressure. For convenient reference, the table on page 87 gives these factors for various pressures, and temperatures of feed water. 86 c < Pi o Oh > o o o < JO 3J^dui9X I wrvjiNrjO) -HH-H — oo OC^O^C^CCCCOCI- OM'Nri-ti-.wOOOOO'O^ O^oO cC CC i- i - N rj M rj (N ^ ^ ^ -. w w HH K. ^ o c c c c OfN"Hh-.-.^000 0. c^C^c^oocoocI-^•-I- r^ ro CI M o o 00 t-~ o ■^ (^ n »-. o ox i-^ -o ""j n M (N (v| M ►H M ►H .^ M ^ M w H- c c o c o O r^-^MCO >Of^ O r-n-'-'X'O -^o-o f^CO O w M «-( O C O O OOOOOOOCC i-i-t^i^-C ^fOM M O OX) r-i^-T^ri I- O OOC r^NC i^j rjfNCICirjMMMWMWWWMCCCCC ^>^M oo ^O r-i/5'^l oo '^'-'OC -tn-oc lA^ O'-' O O O O OOOccxoCcc i-r--r~-000 '^'-O'N >-i O OI-^O lO-t^ri i-H C OOC t-'sC i^. fICl(M01(N.-^MM^WMMWI-CCOOC O r^'i-'-'CC in'V] o t-^'^'-iooo i^OO "^CO OO O O OOO O. 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It may be saturated in quality, or superheated, but it must not be wet. Dry steam, or, as it is called technically, saturated steam (mean- ing steam saturated with heat), is steam in its natural or normal condition. If any heat is added it immediately becomes superheated, and it should be noted that it cannot become superheated until it has first become dry, while if any heat is taken away from saturated steam, a portion of it is at once condensed to the form of moisture. The steam that remains, how- ever, is itself dry, and what we know as wet steam is really a mixture of dry steam and small particles of moisture which are mechanically mixed with it and carried along in the current. The question of making dry steam, therefore, is one of properly liberating the bubbles of steam from the surrounding water so that none of the latter shall be entrained with it. As is well known, the immediate predecessor of the water-tube boiler in marine work was the cylindrical or Scotch boiler of large diameters. The Babcock & Wilcox Boiler is built with a steam and water drum of less than four feet diameter, and herein is one of its great elements of light- ness and safety. But, on account of this smaller diameter, and consequent reduction of liberating surface, there might be apprehension that the qual- ity of the steam would be affected and that considerable moisture would be entrained. This, however, is not the case, as shown by the following statements of prominent engineers who have obtained their knowledge from actual tests and experience with the boiler : " The moisture in the steam is so infinitesimal as to be entirely ncgligil)le in the final results." — Lieutenants B. C. Bryan and IT. IT. White, U. S. N. " The calorimctric experiments show the steam to have been perfectly dry." — Chas. E. Emery, Ph.D. "Percentage of moisture in steam — ^part of i jjcr cent. — -.3 to .5." — /. M. Whitham, Mem. Am. Sac. M. E. "At the highest rates of forcing, the moisture entrained in the steam never exceeded 3<4 of i per cent." — Ernest H. Peabody, Mem. Am. Soc. M. E. "Moisture in steam, 0.48 of i per cent., or practically dry." — Robert Logan, N.A. " The calorimeter showed .72 of i per cent, of moisture at the throttle valve, or practically dry steam." — /. E. Denton, Prof, of Mechanical Engineering, Stevens Institute of Technology. Even more convincing is a study of the reports of tests in the follow- ing pages, where it will be found that, at moderate rates of combustion, the steam is dry, and, even when evaporating 16 pounds of water per sq. ft. of heating surface (test of "Wyoming " boiler with oil fuel) , there was only eight- tenths of one per cent, of moisture. The combustion was, in this. case, equivalent to burning 75 lbs. of coal per sq. ft. of grate surface per hour. The following experiment, made several years ago at the works of this company, serves to show the manner in which steam is separated from the water in this type of boiler, and passes in a dry state to the perforated dry pipe connected with the outlet from the drum. It also proves that the size of the drum has little to do with the dryness of the steam, and that a very small liberating surface in connection with a very little time is all that is needed to insure the proper liberation of the steam from the water. In order to observe the phenomena going on inside the steam drum of a boiler in service, a peep-hole, filled with a stout piece of glass, was made in each drum-head, opposite the space between the return circulating tubes and the baffle plate. By means of an electric arc light placed at one eyepiece, the interior of the drum was illuminated and the discharge of each of the circulating tubes distinctly seen. When the boiler was steaming rapidly, with ^i inch air blast in the ash pit, the observations clearly showed that each of the circulating tubes was discharging against the baffle plate, with considerable velocity, a stream of solid water that filled the tube for half its diameter. There was no spray or mist whatever, showing conclusively that the steam had entirely separated from the water during its passage through the circulating tubes, which, in this boiler, were only 50 inches long by 4 inches in diameter. As a matter of fact, the actual steam liberating surface required for the entire boiler was less than that contained in the circulating tubes, which amounted to about 15 square feet, or i square foot to every 100 square feet of heating surface in the boiler. After striking the baffle plate, the water was deflected downward, mixing with the main body of water in the drum, while the steam passed 90 around the ends of the baffle plate into the steam space in which is located the dry pipe. The drum itself is not exposed to great heat in this type of boiler, and the water in it is not agitated in any way, so that there is no possibility of water or spray reaching the dry pipe. In view of this experiment, it is evident that the Babcock & Wilcox marine boiler cannot furnish anything but dry steam. In any ship or other installation of boilers, however, it must be remem- bered that after leaving the generator the steam passes at once into a system of piping, which, even if well covered, is always being more or less cooled by the surrounding air. This cooling effect necessarily condenses some of the steam and it has often happened that samples of steam have been tested which, by accident, contain some of this condensation from the sides of the pipe. Such tests are not only manifestly unfair to the boiler, but are very misleading in their results. METHOD OF TESTING STEAM The method best adapted to insure obtaining a fair sample of steam for testing, is to take it from the center of the vertical portion of the steam pipe as near the boiler as possible. Use a straight open-ended nipple, pro- vided with a long thread on one end n^perforateo so that it may be screwed into the - ,1 i 15 " "^ ^V-S-. steam pipe far enough to bring the open end at or near the center of the current of steam ascending from the boiler, and as far removed as possible from the sides of the pipe, which are always coated with a thin film of moisture. Do not use perforated or slotted nipples, as they have been found to give very inaccurate results. The throttling calorimeter, first devised by Prof. C. H. Peabody, of the Massachusetts Institute of Technology (see Journal of Franklm In- stitute, August, 1888), is by far the simplest type of instrument for testing the quality of steam, and, when properly used, gives very accurate results. There have been numerous forms of this instrument, one of the simplest being that designed by Mr. George H. Barrus, of Boston, which is described below. Steam is taken from a >2 -inch pipe provided with a valve, and passed through two 3^-inch tees situated on opposite sides of a ^-inch flange union, substantially as shown in the accompanying sketch. A thermometer cup, or well, is screwed into each of these tees, and a piece of sheet-iron, perforated with a I -inch hole in the center, is inserted between the flanges and made tight with rubber or asbestos gaskets, which also act as non- THERMOMETER CUP 91 SIX I'ROTKCTKI) CKl'ISKKS "TACOMA," " CLEVELAND," " DENVER," " GALVESTON," "CHATTANOOGA" AND "DES MOINES" Alt. Kitted with Babcock & Wilcox UOII.ERS Armiigcment of Boiler Rootns: Total Heating Surface . 13200 sq.ft. Total Grate Surface . 300 sq. ft. Ratio H. S. to G. S.,44: i FRAME 42 LOOKING FORWARD 92 conductors of heat. For convenience, a union is placed near the valve, as shown; and the exhaust steam may be led away by a short i^-inch pipe, shown by dotted lines. The thermometer wells are filled with mercury or heavy cylinder oil, and the whole instrument, from the steam main to the i>4-inch pipe, is well covered with hair felt. Great care must be taken that the l-inch orifice does not become choked with dirt, and that no leaks occur, especially at the sheet-iron disc, also that the exhaust pipe does not produce any back pressure below the fiange. Place a thermometer in each cup, and, opening the y^-mch. valve wide, let steam flow through the instrument for ten or fifteen minutes; then take frequent readings on the two thermometers and the boiler gauge, say at intervals of one minute. The throttling calorimeter depends on the principle that dry steam when expanded from a higher to a lower pressure, without doing external work, becomes superheated, the amount of superheat depending on the two pres- sures. If, however, some moisture be present in the steam, this must necessarily first be evaporated, and the superheating will be proportionately less. The limit of the instrument is reached when the moisture present is sufficient to prevent any superheating. Assuming that there is no back pressure in the exhaust, and that there is no loss of heat in passing through the instrument, the total heat in the mixture of steam and moisture before throttling, and in the super- heated steam after throttling, will be the same, and will be expressed by the equation H-^ = 1150.4 + 47 i.t - 212) H — 1150.4 —.47 {t — 212) ^^ or X = — ^ -t -r/ V / s^ jQQ in which :\: = percentage of moisture; ii^ = total heat above 32° in the steam at boiler pressure ; L = latent heat in the steam at boiler pressure ; 1 1 50.4 = total heat in the steam at atmospheric pressure; /= temperature shown by lower thermometer of calorimeter; 212 = temperature of dry steam at atmospheric pressure. Theoretically the boiler pressure is known from the temperature of the upper thermometer; but, owing to radiation, etc., this is usually too low, and it is better to use the readings of the boiler gauge, if correct, or better still to have a test gauge connected on the >^-inch pipe supplying the calorimeter. If the instrument be well covered, and there is as little radiating sur- face as possible, the above assumption that there is no loss of heat in pass- ing through the instrument may be nearly, though never quite, correct. On 93 94 the other hand it is more than hkely to be very far from correct, and, to eHminate any errors of this kind, Mr. Barrus recommends a so-called "calibration" for dry steam. This, again, involves the assumption (which is open to some doubt) that steam, when in a quiescent state, drops all its moisture and becomes dry. No other practical method, how- ever, has been proposed, and this is, therefore, the only method used at the present time. Some engineers, however, refuse to make any cali- bration, but, instead, make an assumed allowance for error. To make the calibration, close the boiler stop valve, which must be on the steam pipe beyond the calorimeter connection. Keep the steam pres- sure exactly the same as the average pressure during the test, for at least fifteen minutes, taking readings from the two thermometers during the last five minutes. The upper thermometer should read precisely the same as during the test, and the lower thermometer should show a higher tempera- ture; this reading of the lower thermometer is the calibration reading for dry steam, which we will call T. Calculation of results, allowing for radiation by calibration method: 47 {T - t) Formula, x = X loo L in which x = percentage of moisture; 7"= calibration reading of lower thermometer; / = test reading of lower thermometer; L = latent heat of steam at boiler pressure. The method of taking a sample of steam from the main is of the greatest importance, and more erroneous results are due to improper con- nections than to any other cause. Use only a plain, open-ended nipple projecting far enough into the steam pipe to avoid collecting any conden- sation that may be on the sides of the pipe. Take care that no pockets exist in the steam main near the calorimeter, in which condensation can collect and run down into sampling nipple. Remember you are ascertain- ing the amount of moisture in the steam and not measuring the conden- sation on the walls of the steam piping. Make connections as short as possible. As mentioned above, there is a limit in the range of the throttling calorimeter which varies from 2.88 per cent, at 50 pounds pressure to 7.17 percent, at 250 pounds. When this limit is reached a small separator may be interposed between the steam main and the calorimeter, which will take out the excess of moisture. By weighing the drip from the separator and ascertaining its percentage of the steam flowing through, and adding this to the percentage of moisture then shown by the throttling calorimeter, the total moisture in the steam may be ascertained. It is seldom, however, in a well-designed boiler, that any but a throttling calorimeter becomes necessary. 95 96 ECONOMY DUE TO THE HEATING OF FEED WATER THE importance of heating feed water before delivering it to a boiler can best be realized by considering exactly what takes place during the generation of steam. As explained on page 80, the total heat in steam consists partly of sensible heat, which marks the boiling point of the water, and partly of latent heat, which converts the water into steam. Therefore, in generating steam in a boiler, the water must first be heated to the boiling point and then enough heat added to evaporate it at the required pressure. PERCENTAGE OF FUEL SAVED BY HEATING FEED WATER (Pressure i8o pounds per gauge) Initial Final Temperature — Degrees Fahrenheit Degrees Fahrenheit 120° 140 160° 180° 200° 250° 300° 32° 7-35 9.0: I 10.69 12.36 14.04 18.20 22.38 35 7.12 8.7c ) 10.46 12.14 13.82 18.00 22.18 40 ( 5.72 8.4 [ 10.09 11.77 13-45 17-65 21.86 50 5-93 7 A 5 9-32 11.02 12.72 16.95 21.19 60 5-13 6.8. ^ f^-55 10.27 11.97 16.24 20.52 70 I-31 6.0- 1- 7-77 9.48 II. 21 15-52 19.83 80 V4« 5-2: J 6.96 8.70 10.44 14-79 19-13 90 2.63 A-y ) 6.14 7.89 9-65 14.04 18-43 100 1-77 3-5- \ 5-31 7.08 8.85 13.28 17.70 no .89 2.6i ^ 447 6.25 8.04 12.50 16.97 120 .00 i.8( ) 3.61 5-41 7.21 11.71 16.22 130 •9 2.73 4-55 6.37 10.91 15-46 140 .0( ) 1.84 3-67 5-51 10.09 14.68 150 •93 2.78 4-63 9.26 13-89 160 .00 1.87 3-74 8.41 13.09 170 ■94 2.83 7-55 12.27 180 .00 1.91 6.67 11-43 190 .96 5-77 10.58 200 .00 4.86 9.71 210 3-92 8.82 The rate at which water absorbs heat varies slightly as its density decreases, but for rough calculations it can be assumed that the number of degrees Fahrenheit which a pound of water is heated, represents the number of British thermal units it has absorbed. Suppose, therefore, that a boiler is making steam at 180 pounds gauge pressure and is being fed with water at 60 degrees Fahrenheit. By reference to the steam tables, we find that the boiling point at 180 pounds gauge pres- sure is about 380 degrees Fahrenheit, and the latent heat equals about 845 heat units. When the water goes into the boiler, therefore, it has first to be heated from 60 degrees to the boiling point, which requires approximately (380 — 60) 320 heat units. This, with the latent heat afterwards added to convert it 97 into steam, makes a total of (320 + 845) 1 165 heat units which must be added to each pound of water entering the boiler to make one pound of steam. If instead of entering the boiler at 60 degrees, the feed water were heated to 200 degrees Fahrenheit, only (380 — 200) 180 heat units would have to be added to bring it to the boiling point instead of 320 as before, and the total heat added per pound of steam would be (180 + 845) 1025 instead of 11 65 heat units. In other words, to each pound of water con- verted into steam the boiler would now have to add only 88 per cent, of the amount of heat it did before, and 12 per cent, of the coal might be saved, or, providing the same amount of coal was burned on the grates, it would make nearly 14 per cent, more steam than it did with feed water at 60 degrees. The table on page 97 shows the saving that may be expected by heating feed water various amounts. Another very convincing way of looking at this matter is from the view of engine efficiency. The best engine yet designed, with all the modern improvements of high steam pressure, multiple expansion, condensers, etc., cannot possibly use more than one-fifth of the heat contained in the steam, because of the latent heat necessarily discharged in the exhaust. How very much more wasteful then must be the pumps, blower engines, and other auxiliary machinery on board ship, even if, as is often the case, they exhaust into the condenser. It is the general impression that auxiliaries wdll take much less steam if the exhaust is turned into the condenser, thereby reducing the back pressure. As a matter of fact, vacuum is rarely registered on an indicator card taken on auxiliary cylinders unless the exhaust connection is short and with- out bends, long pipes and many angles vitiating the effect of the condenser. On the other hand, if the exhaust steam in the auxiliaries can be used for heating the feed water, all the latent heat of this steam, except what is lost by radiation, goes back to the boiler and is saved instead of being thrown away in the condensing water or wasted with the free exhaust. Taking the whole plant into consideration, this makes the auxiliary machinery more efficient than the main engine. For illustration, take the first of the series of tests of the steamship " Pennsylvania," as found on page 145. The total amount of steam furnished per hour was 20,407 pounds, of which 17,252 pounds were used in the main engine and 3155 in the auxiliaries, i.e., the auxiliaries required 15.46 per cent, of the total steam. Of the 3155 pounds of auxiliary steam, 139 pounds were used by the stoker engines and exhausted into the ash pits, leaving 3016 pounds that exhausted into the heater. The feed water was taken from the hot well at a temperature of 99.3 degrees Fahrenheit and pumped through a closed feed-water heater, where it was heated to 222 degrees Fahrenheit by means of the exhaust steam from the auxiliary machinery. From this heater it passed to the boilers and 99 100 was converted into steam at a pressure of 242 pounds. The auxiliaries exhausted into the heater at about 3 pounds back pressure. By referring to the steam tables, it will be found that the 3016 pounds of steam supplied to the auxiliary machinery contained 3,624,930 British thermal units (120 1.9 X 3016). At 3 pounds back pressure the same amount of steam consumed would contain 3,480,162 British thermal units. The difference between these amounts — 166,483 British thermal units — is all that is available for doing useful work, and as no engine can use all of this with- out waste, it will be seen that the proportion of heat that is converted into work is very small indeed. If the exhaust steam from the auxiliary machinery had been turned into the condenser, it is true that not quite so many pounds would have been required each hour, but all the latent heat would have been thrown away in the condensing water, while as a matter of fact, by sending it into the feed-water heater, over three-quarters of the entire 3,480,162 British thermal units were saved. This is shown by the heat units absorbed by the feed water which was heated from 99.3 degrees to 222 degrees, a difference of 122.7 degrees Fahrenheit. This multiplied by the number of pounds heated gives (20,407 X 122.7) 2,503,939 British thermal units as the actual amount of heat taken from the exhaust steam of the auxiliaries each hour and returned to the boiler. Of the remaining 976,123 British thermal units, part is lost in radiation, condensation in the pipes, etc., and part, amounting to nearly 600,000 British thermal units, is wasted in the drips from the heater, on account of the impossibility of cooling the condensed steam much below 222 degrees Fahrenheit. It may be noted, further, that each pound of coal burned contained 11,790 British thermal units, of which 75.7 per cent., or 8923 British thermal units were utilized in making steam. If, therefore, 2,503,939 heat units had not been saved by heating the feed water, it would have been necessary to have heated the same by an additional expenditure of 280 pounds of coal per hour, thereby increasing the total coal burned in the plant, per indicated horse-power, to 2.15 pounds instead of 1.92 pounds, as shown by the test. There is another reason for heating feed water, aside from the obvious saving of heat units, and that is the fact that the boiler steams more eco- nomically when using hot feed water than when using cold. This was demonstrated experimentally by Kirkaldy. of England, and the theory ad- vanced by M. Normand seems very plausible, namely, that cold water checks the circulation in the boiler, and in re-establishing this a certain amount of heat disappears in mechanical work, with a consequent loss in evaporation. Water-tube boilers with their rapid and uniform circulation, are not liable to injury by the use of cold feed water, but the above points make it clear that cold water should never be used by the engineer who wishes to obtain the highest economy from his plant. STEAM FROM SUPERHEATER STEAM 10 SUPERHEATER BABCOCK & WILCOX SUPERHEATER — PATENTED 102 Bx^BCOCK & WILCOX SUPERHEATER THE illustration on the opposite page shows a cross-section of a Babcock & Wilcox Marine Boiler fitted with a superheater. From this it will be seen that the superheater is composed of a series of tubes bent into U-shape and expanded into forged- steel headers which run across the boiler at right angles to the tubes. The length of the headers and the number of tubes depends upon the degree of superheat required. The superheater is placed in a box which is arranged to form a continua- tion of the first and second passes for the gases of combustion as they pass around the tubes of the boiler, so that the superheater is located where there is a great difference of temperature between the hot gases and the steam, and not, like the old-fashioned ones, in the uptake, where this difference was smaller. In order that the steam as it passes through the superheater may be thoroughly exposed to the hot gases, removable baffles or division plates are put in the headers of the superheater, two in the upper header at one quarter of the length from each end and one in the lower header at mid- length. The result of this location of the baffles is to force the steam as it goes through the superheater tubes to pass through the hot gases eight times, thereby giving ample opportunity for the elevation of temperature to the desired extent. Superheater tubes are 2 inches in diameter and are arranged in groups of four, accessible from a single handhole just as are the tubes in the boilerheaders, thus affording ready access to any tube for expanding or renewal. The plates for these handholes are interchangeable with those on the boiler headers. DANISH FISHERY PROTECTION S. S. "ISLAND'S FALK." BABCOCK & WILCOX BOILERS. 1200 Horse-power 103 ECONOMY DUE TO SUPERHEATED STEAM IN MARINE PRACTICE* By Walter M. McFarlaxd, AI.A.S.M.E. THE theoretical advantages of the use of superheated steam were evident when the principle of the Carnot heat cycle was under- stood. In the early days, when steam pressures were low, the economy due to a very much higher initial temperature with no increase of pressure was, of course, obvious. Accordingly, a number of plants were installed using superheated steam. On the whole, these early installations were not practical successes, on account of the rapid corrosion of the superheaters, although the heat economy was obtained. In those days the causes of corrosion were not properly understood so that the measures taken to prevent corrosion often increased it. In more recent years, since the means for preventing corrosion are fairly well known, the attractiveness of the benefit to be derived from super- heating has led to its reintroduction. An excellent article by Capt. C. A. Carr, U. S. N., published in the Journal oi the American Society of Naval Engineers for Februar>^ 191 1, gives a great deal of information with respect to land plants, and will repay very careful study. Speaking generally, it is considered that with steam turbines of modern design and carrying from 175 to 200 pounds steam pressure, there is a saving in steam consumption of about i per cent, for each 10 degrees of superheat. About ten years ago, Capt. Augustus B. Wolvin, then the manager of a number of steamboat lines on the Great Lakes, and who has been one of the pioneers in the adoption of improvements in marine machinery tending to economy, installed Babcock &: Wilcox boilers and superheat- ers in one of the vessels under his control, and followed this by similar in- stallations on several other vessels. One of these, the "James C. Wallace, " was subjected to a test by a board of naval engineer officers, and showed a saving in coal of about 9 per cent., with an average superheat at the engine of about 85 degrees. The Bureau of Steam Engineering of the United States Navy took up this subject, and in 1904 ordered Babcock & Wilcox boilers and superheaters to replace the old cylindrical boilers on the " Indiana. " This was followed by installations of similar boilers and super- heaters on the " Massachusetts" and the "New York" (now " Saratoga") in the way of replacements, and on the "Michigan," "South Carolina," "Prometheus," "Vestal," "Delaware," "North Dakota," "Texas." and "New York" (new), new vessels. In 1905 boilers and superheaters from the same makers were ordered for the steamship "Creole," with respect to * Abbreviated from International Marine Engineering. 104 whose performance some interesting data will be given later on. The Pennsylvania Railroad has always shown a desire to get the safest and most efficient machinery in its marine service, and in 1909 ordered from this con- cern boilers and superheaters for three of their large tugs, the "Johns- town," "Wilmington," and " Harrisburg, " which have given great satisfaction and economy in service. The steam yacht "IdaHa" also has a boiler and superheater supplied by this same firm. Table IX. gives the performance of the steamship "Creole," which is TABLE IX.— ECONOMY DUE TO SUPERHEATED STEAM— MERCHANT VESSELS Name of vessel Date of tests Length, feet Beam, feet Draft, feet Tonnage, gross Tonnage, net Cylinders, diameter and stroke L H. P Boiler pressure, pounds Kind of boilers Ratio of superheating to evaporating surface per cent *Av. coal per trip for five round trips, tons . . Percentage of saving by use of B. & W. boiler and superheater Av. coal per trip for two round trips, each vessel, in October, 19 10 Percentage of saving by use of B. & W. boiler and superheater Creole 1910 407 53 26.7 6,754 4.302 (2) 27^4, 46} 2, 79.42 7,000 210 Babcock & Wilcox with superheaters. 15-5 1,149 ti6.38 1,206 ti745 Momus and Antilles I 908-9- 10 410 53 25.6 6,878 4,326 (1)34,57,104, 63 7,500 2IO Scotch, no superheater. 1,374 1,461 * The "Creole's" trips were in summer of 1910; those of the other ships are their most eco- nomical trips in summers of 1908, 1909, and 19 10. t The improved economy is due partly to greater efficiency of boilers of " Creole" and partly to superheat. See text for analysis and discussion. fitted with Babcock & Wilcox boilers and superheaters, as compared with the performance of her two sister ships, the "Momus" and "Antilles, " which have ordinary cylindrical boilers without superheat. As shown by the table, the hulls are practically identical. The "Creole" has twin screw engines of about 7000 horse-power, while the "Momus" and "Antilles" have single screw engines of about 7500 horse-power. All three ships carry the same steam pressure — about 210 pounds. The "Creole" was originally (1905) fitted with Curtis turbines, but the speed was too low (i5/^ knots) to permit economical use and they were removed. It is to be noted that so far as there is any advantage in engine economy it should be with the " Momus " and "Antilles, " which have each a single engine of about the same power as the aggregate of the two engines on the "Creole," thereby reducing the 105 losses due to cylinder condensation. The engines are all triple expansion and of excellent design. The "Creole's " first trip with her new engines was made in the spring of 1910. Two comparisons are given, one of five round trips of the "Creole" in the summer of 1910, as compared with five round trips of each of the others, obtained by taking their best performances in the three summers of 1908, 1909, and 1910. The second comparison is between two round trips of all three vessels made in the month of October, 1 910. They run over the same route from New York to New Orleans, and, as the hulls are identical and the engines designed and built by the same firm, the only material difference is in the boilers and superheat. The table shows that the "Creole" operates with about 17 per cent, less fuel per round trip than her sister ships. The average superheat carried is about 60 degrees, from which a saving of about 6 per cent would be expected. It is to be noted, however, that there is a distinct gain in economy due to the use of the Babcock & Wilcox boiler, as contrasted with the cylindrical or Scotch boiler. In an article by the late Admiral George W. Melville, U. S. N., pub- lished in the Engineering Magazine for January, 191 2, are given reports of very accurate tests of Scotch boilers* and of Babcock & Wilcox boilers made by boards of navy officers and committees of independent engineers, so that the reliability of the data is beyond question. These tests showed that, at the rate of combustion obtaining in these vessels, the Babcock & Wilcox boiler shows an efficiency of about 74 per cent., as against from 62 to 67 per cent, (average 64.5 per cent.) for the Scotch boiler. Working out the saving due to this greater efficiency, it comes to 11.7 per cent, and this subtracted from 17.45 per cent., the total saving, leaves 5.75 per cent, as the saving due to superheat, which agrees quite well with the rough general rule of I per cent, saving for each 10 degrees of superheat. Table X. gives the performance of four United States naval vessels, all of the same displacement and approximately the same power, and all fitted with Babcock & Wilcox boilers. The " Kansas " and the " New Hampshire " have no superheaters, while the "Michigan" and the "South Carolina" are fitted with superheaters. The performance of these four ships is very interesting, showing a saving, based on the average of the two ships, with superheaters as contrasted with the two without, of 18.52 per cent. In this connection it is interesting to note the remarks of Commander Henry C. Dinger, U. S. N., formerly editor of the Journal of the America)! Society of Naval Engineers, who says with respect to the better performance of the ships with superheaters: "This shows a gain of about 16 per cent, over previous navy practice; of this gain one half may be assigned to the use of superheated steam, and the other due to reduction of clearance and better cylinder proportions." *This report is reproduced on p. 58. 106 TABLE X.— ECONOMY DUE TO SUPERHEATED STEAM. OFFICIAL TRIALS OF UNITED STATES NAVAL VESSELS Name of Vessel Builders Date of trial ■ ■ • Displacement on trial, tons Twin screw engines, diameter and stroke of cylinders, inches Kind of boilers Evaporating surface in use, square feet . Superheating surface in use, square feet . Ratio superheating to evaporating surface, per cent Heating surface, total square feet Grate surface, total square feet Ratio evaporating to grate surface Speed, average for trial (4 hours) Revolutions, average per minute (4 hours) Steam pressure at boilers, gauge, pounds . Steam pressure at high-pressure steam chest, gauge, pounds Steam pressure, first receiver, absolute, pounds Steam pressure, second receiver, absolute, pounds Vacuum in condensers, inches of mercury Superheat at high-pressure chest, degrees Fahrenheit I. H. P. of main engines only I. H. P. of all auxiliaries in use .... I. H. P. total Coal per hour per I. H. P. of main engines Coal per hour per I. H. P. of main engines and all auxiliaries Coal per hour per square foot grate surface Air pressure in fire-rooms, inches of water Kansas New York Shipbuilding Co. Dec. 14, 1906. 16,000 321^,53.(2)61; 48 Babcock & Wilcox 52,752. No superheaters 52,752 1,097 48.0 to I 18.004 121.32 278.2 250.0 106.5 38.0 28.0 None 19,302.00 455-00 I9.757-00 1-779 1-737 31.21 0.60 New Hampshire New York Shipbuilding Co. Dec. 20, 1907. 16.145 32^.53. (2)61:48 Babcock & Wilcox 47,112 No superheaters 42.8 47.1 12 1,100 I to I 18.162 118.75 246.00 222.00 32-20 25.60 None 16,772.00 495-00 17,267.00 1-785 1-773 27.21 0.49 Michigan New York Shipbuilding Co. June 10, 1909, 16,064 32, 52, (2) 72:48 Babcock & Wilcox 42,432 5. 174 12.2 47,606 1,046 40.6 to I 18.79 119.46 297.70 246.00 77.40 8.10 27.00 85.70 16,016.4s 500.85 16,517.30 I-51 1.46 23.28 0.67 South Carolina Wm. Cramp & Son S. &E. B.Co. August 25, 1909. 16,064 32, 52, (2) 72:48 Babcock & Wilcox 42,432 S.174 12.2 47,606 1,046 40.6 to I 18.86 121.28 285.00 241.00 96.50 35-10 26.2 47-5 17,651.00 706.00 18,357-00 1.395 1. 341 23.47 In October, 1909, a test was made of the machinery of the yacht " IdaHa " with superheated steam. She has a four-cyhnder triple-expansion engine, the cyHnder diameters being 11.5 inches, 19 inches, (2) 22.7 inches by 18 inches stroke. All the cylinders are un jacketed and have piston valves. There is one Babcock & Wilcox boiler, with 65 square feet of grate surface and 2500 square feet of evaporating surface and 340 square feet of superheating sur- face. These tests are notable from the fact that the weight of the steam used was carefully determined by weighing the steam condensed in tanks on carefully standardized platform scales. The actual duration of the test in each case was about 2^ to 3 hours, but observations were made every 15 minutes. The results are given in Table XI. The duration of the experi- TABLE XL— ECONOMY OF SUPERHEATED STEAM. TESTS ON YACHT "IDALIA." SUMMARY OF TESTS Conditions Pressures Vacuum Temperatures Date, 1909 Throttle First Receiver Second Receiver Feed Hotwell Oct. II Oct. 14... . Oct. 14.... Oct. 12... . Oct. 13.... Saturated Superheat, 57°... Superheat, 88°... Superheat, 96°... Superheat, 105°.. 190 196 201 198 203 68.4 66.0 64.3 61.9 63.0 9-7 9-2 8.7 7-8 8.4 25-S 25.9 25-9 25.4 25-2 201 206 205 202 200 116. 109-5 115-0 III. 5 III.O R. P. M. I. H. P. Main Engine Water per Hour Total Water per I. H. P. Per- cent. Saving of Steam Date, 1909 Conditions Air Pump Circulat- ing Pump Main Engine Oct. II... . Saturated Oct. 14.. .. Superheat, 57°.. . Oct. 14 iSuperheat, 88°.. . Oct. 12.. .. Superheat, 96°... Oct. 13.. .. Superheat, 105°.. 57 56 53 54 4-; 196 198 196 198 197 194-3 191-5 I9S-I 191-5 193-I 512.3 405-2 521. 1 408.3 502.2 9.397 8,430 8,234 7,902 7,790 18.3 17.0 15-8 15-8 15.5 7.10 13.66 13.66 15.30 io8 ments was obviously too short to make it worth while to attempt to measure the coal. It is to be noted that the feed, air, and circulating pumps, all of which are independent, discharge their exhaust steam into the main con- denser, so that the figures given for steam per horse-power include the steam used by these auxiliaries, as well as by the main engine, while the horse- power is of the main engine only. We have now given such experimental data as are available of measure- ments of coal and water to show the economy of superheating, and, as stated above, they bear out the rough rule that there is about i per cent, in saving of fuel for each lo degrees of superheat. The practical effect of superheated steam is, of course, to give a greater thermal efficiency to the engine in which it is used and reduce the number of pounds of steam required per horse-power. The question has frequently been raised whether there is a corresponding saving in fuel. Speaking generally, it may be asserted that with superheaters properly designed and located, and within the limit of superheat ordinarily used in marine practice ■ — 50 to 100 degrees — such tests as have been made, and such general ex- perience as has been gained, tend to show that there is almost exactly the same percentage of reduction in the amount of fuel used as in the amount of steam per horse-power. It is not difficult to understand why this should be the case in a properly designed arrangement of superheaters. In all the cases cited, and these are the only ones for which data are available, the superheaters are used with Babcock & Wilcox boilers. As is well known, a system of baffling is used in these boilers which causes the hot gases to cross the tubes three times on their way from the furnace to the up-take. The superheaters are placed at the passage from the first to the second pass, after the gases have crossed the tubes once and before they cross the second time, so that the temperature is very much higher than in the case of the older types of superheaters, where they were placed in the up-take like a feed-water heater. The experiments which have been made on these boilers under various rates of combustion show that the temperature where the superheater is located, when burning from 30 to 35 pounds of coal per square foot of grate, would be about 1000 degrees Fahrenheit, while the temperature of saturated steam of 200 pounds is 388 degrees Fahrenheit. There is thus a good difference in temperature, so that a considerable degree of super- heat is obtained with a moderate amount of superheating surface. There are still the second and third passes of the boiler to be acted upon by the hot gases, and the only effect is to reduce slightly the temperature of the gases in the up-take. Hence the efficiency of boiler and superheater is at least as great as that of the boiler alone. The examples we have given of the naval vessels, of the " Creole " and her sister ships, and the "Wallace," with and without superheat, all show results as measured in coal, while the "Idalia" experiments give them in water. 109 None of these experiments has the conditions absolutely ideal for determining with extreme accuracy the exact amount of gain due to superheating, because other items vary besides the extent of superheat. What practical men desire to know, however, is not results to the last decimal point, but to be reasonably sure that there is a decided gain due to superheating, and this has, from the data given, been shown beyond question. Obviously, thoroughly dry steam, as against very moist, would be a blessing in reciprocating engines, so that this, of course, is another benefit of superheating. On board ship, where there are so many auxiliary engines scattered over a large area, and many of them simple cylinders following full stroke, it can readily be seen that the use of superheated steam ought to be conducive to a great increase of economy. In the central stations and power houses on shore, before the use of superheated steam, many of the valves and fittings in the pipe lines were of cast iron. It was found that superheat of loo degrees, or higher, caused considerable trouble, due to dis- tortion of the cast-iron fittings and inability to keep the valves tight. The general practice now is to avoid the use of brass or cast iron, and the valve bodies and fittings which come in contact with superheated steam are to be of cast steel. Valve seats are made of bronze with a large percentage of nickel, or of Monel metal, which is a natural bronze of somewhat similar com- position. The navy is now using Monel metal valves and seats. With these precautions, experience has shown that superheated steam up to loo degrees can be used with great satisfaction as far as practical service is con- cerned, with no increased cost of repairs and with decided increase in efficiency. .11 k; r REBOILRRING THE UNITED STATES MONITORS AT the breaking out of the war with Spain, the United States Govern- ment found it necessary to commission every available ship then in ordinary; among these vessels were the old single turret monitors, which were capable of doing good service as harbor defence vessels, provided they could be reboilered at once. The contract for this work on the " Canonicus," " Mahopac" and "Man- hattan," stationed at League Island Navy Yard, Philadelphia, was awarded to The Babcock & Wilcox Company, and the first two vessels were made ready for steam in thirty days and the third in forty-two days after the order to proceed with the work was received. As the boilers were built in sections, the Government saved much time and expense by passing them into the vessels through the seven-foot armored funnel. Cutting of the decks was thereby entirely avoided. Originally, each monitor was fitted with two fiat-sided Stimers fire- tubular boilers, one on either side of a fore and aft fire-room. As soon as one old boiler was cut up and removed, the work of installing the new boilers began, so that construction progressed on one side of the ship while the second boiler was being demolished on the other. The new boilers con- tained a total of 6000 square feet of heating surface and 200 square feet of grate. Steam was supplied to a pair of horizontal, crank-and-lever, Ericsson engines, having cylinders 48 inches in diameter and 24 inches stroke. To economize space and obtain a low center of gravity, the cylinders were placed athwartships on the same axial line, and as both were fitted with 16-inch trunk pistons, the effective annular area of the crank end was equivalent to that of a circle 45 inches in diameter. In order, therefore, to equalize the power developed on each side of the piston, it was necessary to allow the steam to follow further on the trunk end than on the head end. As the engines were constructed before the advent of high pressures, only 50 pounds initial could be carried in the cylinders, although the boilers were constructed for a working pressure of 1 75 pounds. It is conceded by the best authorities that the time employed in building and installing the boilers is the quickest on record, and, as to steaming, the Navy Department states: "It is a source of satisfaction that the per- formance of these vessels with the new boilers exceeded that obtained when the vessels were first built." 113 "4 EXAMPLES OF DURABILITY IN the earlier editions of Alarine Steam it was thought well to insert a few pages giving some examples of the durability and small amount of repairs required for Babcoek & Wilcox Boilers, inasmuch as the mistaken idea (already referred to on previous pages of this edition) prevailed to some extent that the boiler is delicate and requires very care- ful handling. As already shown by comparing the scantlings of the Bab- cock & Wilcox Boiler with those of the cylindrical boiler, it is easily seen that the former is even more rugged in those parts which give out first, namely, the tubes, than the latter. Instances were quoted in the earlier editions of the large amount of steaming which had been done by various vessels with few or no repairs, but there had not then been a sufficiently long interval since the installation of the boilers to give the time element its due weight. In 1910, letters were written to users of Babcoek & Wilcox Marine Boilers to get expressions of opinion as to the durability of and general satisfaction with the boilers, and some specimen extracts from the answers will be instructive. The chief engineer of a large Lake steamer says : "We have two of your boilers that have been in use for eleven years. They have always given plenty of steam and we have had no trouble in keep- ing up the boilers." Another case is that of a dredge employed by the Engineer Corps of the Army on the Pacific Coast. There are two boilers with oil fuel. These have been in use for five years, working with a pressure of 200 pounds. The total cost of repairs for the two boilers for the five years has been about three hundred eighty-five dollars ($385.00) and the report is that the general performance of the boilers has been highly satisfactory and economical. In connection with the fire-boats "Daniel T. Sullivan" and "David Scannel," of which illustrations are given elsewhere, the consulting engineer who selected Babcoek & Wilcox Boilers for them says: "I will state that these boilers were selected because of the exceedingly low cost of maintaining boilers of the same size and capacity in two towboats, which have been operated for a number of years on San Francisco Bay under my observation. The boiler on each of these boats has about 2770 square feet of heating surface and is called upon to evaporate from 12,000 to 14,000 pounds of steam per hour. During the last eight years, the expense of maintaining one of these boilers has not exceeded $20.00 per year." Babcoek & Wilcox boilers were installed on the fire-boat "W. S. Grat- tan" in 1900. In 1910, the Buffalo Fire Department wrote, 1 1 6 "We wish to advise that Ave have not cut down the steam pressure on these boilers but still maintain a pressure of 225 pounds. These boilers have given entire satisfaction." Inquiry has recently been received, after fourteen years of service, from one of the early installations on the Pacific Coast for some new headers, thus giving some idea of the durability of this part of the boiler. The early installations of boilers on the Great Lakes are running with the original tubes, so that, under the conditions there obtaining, the life of the tubes has been at least twelve or thirteen years. The best possible testimony, however, to the durability of the boilers and general satisfaction with them is a repetition of orders from users who have had long experience with them. We have recently had the ninth repeat order from one firm which has been using our boilers for the last ten years. We have also received orders recently for three separate sets of boilers from a large corporation which has had ten years' experience with the first installations, and, prior to these last orders, had placed our boilers in nine vessels. The Municipal Ferry of New York has just made a contract for a new boat with our boilers after nearly ten years' experience with them on five others, the largest and fastest ferry-boats in the world. After six years experience with our boilers in two fire-boats, the Fire Department of New York City is using them again in a new fire-boat just completed. After investigating the experience in New York, Buffalo and San Francisco, the Boston Fire Department installed our boilers in a new fire- boat and to replace an old shell boiler in another. An order for four boilers was placed with us this year by a user who has had nearly twenty years' experience with our boilers, on a large number of vessels. All of the foregoing instances are in the merchant service, where the weight-saving feature of the Babcock & Wilcox boiler is not so important as in war vessels. The constant succession of orders for vessels of the United States and foreign navies is ample proof of the satisfaction they have given. Every new battleship of the United States Navy launched since 1901 has Babcock & Wilcox Boilers, without mentioning the numerous armored and protected cruisers and other vessels. A majority of the "dreadnought" battleships of the world are fitted with these boilers, and the largest boiler installation in any vessel, naval or merchant, is 87,500 horse-power of Babcock & Wilcox Boilers in the battle-cruiser "Tiger" of the British Navy, 117 FULL-SIZE SECTIOXAL MODEL De.akxm.nt ok .^L^K,^.H Encneerkvu, United States Xaval Academy Ii8 CORROSION-CAUSES AND PREVENTIVE MEASURES AS the life of a boiler mainly depends upon the rate of progress of the corrosion of its pressure parts, the prevention or delay of this destructive action is one of the most important duties of the intelligent engineer. Not only should the subject be studied in its various aspects, but the greatest care and watchfulness are necessary in order to successfully stay the advances of this subtle force. The principal causes of corrosion of iron and steel boilers, in sea-going vessels, can be classified as follows: 1st. Use of sea water. 2d. Acidity — the use of animal or vegetable oils in the steam cylinder. 3d. Admixture of air with the feed water. 4th. Galvanic action. Each of these causes of corrosion, and means of preventing or remedying them, will be considered separately. USE OF SEA WATER Salt water is known to be a solvent of iron or steel, and when boiled under high pressure the magnesium chloride, about 250 grains of which are contained in every gallon, becomes highly corrosive. ANALYSIS OF SEA WATER Carbonate of lime 9.79 grains per gallon Sulphate of lime 114.36 grains per gallon Sulphate of magnesium 134-86 grains per gallon Chloride of magnesium 244.46 grains per gallon Chloride of sodium 1706.00 grains per gallon Total solids 2209.47 grains per gallon Under certain conditions, particularly in the process of corrosion, the water becomes acid by the dissociation of magnesium chloride into hydro- chloric acid and magnesia; the acid, in contact with iron not protected by scale, forms an iron salt which, at the very moment of formation, is neu- tralized by the free magnesia in the water, thereby precipitating oxide of iron and reforming magnesium chloride. Thus it is easily seen that free iron is never found in solution in boiler water. The black and red deposits formed in boilers which have had an excess of sea water in them are generally iron oxides. The red is found when there is much air allowed to get into the boiler; the black when little or no air is present. Just here comes in one of the most astonishing neglects of marine en- gineering. It is the neglect of modernizing the condensers of sea-going ships. 119 To deliberately install an expensive and well-constructed boiler, and as deliberately permit the use, in connection therewith, of condensers known to be subject to leakage, and constructed so as to make quick and efficient repair extremely difficult, is at least commercially criminal. There is far more room for improvement in design and construction of the condensers than in marine boilers, and the great importance of the former is most ob- vious when the first cause of corrosion is properly considered. / _, S. S. "ADELINE SMITH " Owners: Smith LuMnER Co. Badcock & Wilcox Boilers, 1800 Indicated Horse-power Preventive. — To prevent salt feed, the condensers must be tight, and an ample provision made for fresh water "make-up" either by carrying a supply in bulk or by installing an adequate evaporating plant, designed and located so as to operate without priming. If salt feed does enter the boiler, the quantity must not be increased by "blowing off" water from the boiler, at least not until the saturation has reached J'^. A high saturation is preferable to a continuous renewal of salt feed, aside from the heat loss of blowing off. A light scale will reduce the evaporative efficiency of a boiler, in spite of statements to the contrary, and a heavy scale will induce the burning out of parts exposed to the flames. Remedy. — A small amount of salt water is bound to get into the boilers, even under favorable conditions, through priming in the evaporator and sHght leakage from the condenser, and it is an excellent plan to con- stantly use a small quantity of milk of lime to neutralize it. One or two pounds per looo indicated horse-power fed per day, in the manner below mentioned, may suffice. The Hme used is the ordinary unslaked lime of commerce, and it should be finely powdered and kept in a dry place; for instance, on the up-take gratings. Milk of lime is a mixture of about one pound of lime to a gallon of water and should be added at times to the water in the filter box. The Use of Lime. — When starting with new boilers on a voyage for the first time, ten pounds of lime should be put into the boilers for every 1000 horse-power (dissolve in water and put in through man hole); and four to six pounds of lime per day for every lOOO horse-power should be passed through the hot well (as milk of lime) for about six days. At the end of the voyage the boilers should be examined to see if they have a thin coating of lime scale on their interior surface. If this is not the case and the water shows an improper color, the use of the lime should be continued. The rationale of the use of lime is the conversion of magnesium chloride, which is corrosive in effect on iron and steel, into magnesia and chloride of calcium neither of which is corrosive; and the light scale on the surface also prevents the corrosive elements from coming into contact with the iron. Further precautionary methods must be employed by the marine engineer in order to conquer corrosion. The boiler water should be tested daily, and if found to be acid or to contain a larger amount than 50 grains of chlorine per gallon, a remedy must be applied. ACIDITY This cause of corrosion may arise from salt feed, or from the introduc- tion of animal or vegetable oil with the feed water by reason of using such oils in the steam cylinders, the exhaust steam entraining much of it to the condensers. This oil, containing fatty acids, will decompose and cause pitting wherever the sludgy deposit can find a resting place in the boilers. Preventive. — Next in importance to the total exclusion of sea water, is the necessity of keeping oil out of the boiler. Only the highest grade of hydrocarbon oil should ever be used in the steam cylinders, and of this the least possible amount. Also, in lubricating piston rods and valve stems, this same precaution should be observed. For, apart from the evil effects of acidity, the hydrocarbon deposited upon the heating surfaces is most harmful, as a thin film of this deposit forms a complete non-conductor, thereby preventing the heat from passing through into the water, and causing the surfaces to burn, blister and crack. Where surface condensers are used, the feed water should be purified on its way to the boiler by passing it through a cartridge filter, which 121 must be kept clean. A large amount of impurities is thereby caught, and the condition of the feed water materially improved. Remedy. — If the boiler water is strongly acid, a solution of carbon- ate of soda should be added to the feed at the rate of a bucket of soda solution per hour until the water just turns red litmus paper blue, after which daily additions of soda will suffice to keep the water in a safe or alkaline state. Carbonate of soda has also been found effective in cases where scale of sulphate of lime is formed, as it possesses the property of changing the sulphate of lime to sulphate of soda, which is soluble, and therefore, harmless. Carbonate of lime, which is also formed, may be easily blown or washed out. To sum up, oil and salt water should never be allowed to enter any kind of a steam generator, and, where surface condensers are used, the feed water should be purified as much as possible before entering the boiler. Graphite can be used in place of oil as a cylinder lubricant wath equally satisfactory results. In fact, graphite is superior to oil when the steam pressure carried is from 200 to 275 pounds, corresponding to a temperature in the neighborhood of 400° F. Oils containing animal fats produce rapid corrosion and should never be used in the cylinder of a steam engine. Many steam vessels are running without a particle of oil ever being in- jected into either their main or auxiliary cylinders, the slushing of the piston rods being found ample for piston lubrication. ADMIXTURE OF AIR WITH FEED WATER Air has been a well-recognized cause of corrosion for many years, and instances of rapid corrosion have been proved to have been caused by the feed pumps sucking air from the hot well, and the feed being delivered at a level considerably below the water line. The boilers that have been most free from this kind of corrosion are those in which the best means have been adopted to keep out air. Small bubbles of air expelled from the water on boiling, attach themselves tenaciously to the heating surfaces. The oxygen in this air at once begins war on the iron or steel and forms iron rust ; making a thin crust or excrescence which, when washed away by the circulation or dislodged by expansion and contraction leaves beneath a small hole or pit. Pitting, once started, pro- gresses rapidly, as the indentations form ideal resting places for the bubbles of air, and at the same time present increased surfaces to be attacked. "^Thorpe states that "nearly all natural waters contain oxygen in solution, and can only be freed therefrom by prolonged boiling in vacuo. " *Spenmath states that water absorbs oxygen as follows : * " Corrosion of Boiler Tubes in U. S. Navy, " Lt. Com. Walter F. Worthington, U. S. N., Journal of the American Society of Naval Engineers, Vol. XII. 123 At 32" Fahrenheit it will absorb 4.9 per cent, of its own bulk At 50° Fahrenheit it will absorb 3.8 per cent, of its own bulk At 68° Fahrenheit it will absorb 3.1 per cent, of its own bulk *Stromeyer states that under 150 pounds pressure, cold feed water absorbs 3.2 pounds of oxygen per ton. With independent feed pumps there is less opportunity for air to get into the boilers than when the pumps are worked off the engines. Air or oxygen is most corrosive in its action, and this is the reason for the boiler feed delivery pipes being fixed either in the steam space or near the water line. Preventive. — Where possible, the hot well water should be pumped to a filter tank situated eight to ten feet above the feed pump suction valves. By so doing a large amount of air rises and is liberated from the surface of the water, and a head of water at the suction valves of the pump is assured. Remedy. — Salt w^ater absorbs more air than fresh water. Care should be taken to keep the pump glands tight, and to efficiently entrap free air in the air vessels. GALVAXIC ACTION Formerly, nearly all corrosion in boilers was attributed to this cause, and zinc slabs were suspended everywhere possible within the water space. The position of zinc relative to that of iron in the scale of electro-positive metals, causes it to be attacked instead of the metal of the boiler when galvanic action takes place. Preventive, — To afford protection by the use of zinc, however, there must be positive metallic contact between the zinc and iron. Practically, it is impossible to maintain this contact with the usual methods of installation, and it has been shown that no galvanic current exists after a few hours of steaming, in the arrangements ordinarily emi)loyed. Remedy. — The use of zinc, however, should not be abandoned on this account, as it appears still a very important element of protection against corrosion due to air in feed water. Its suspension in drums, and points within the boiler near the entrance of the feed, is recommended as of positive benefit, and, indeed, as long as zinc slabs continue to disintegrate and oxidize in a boiler, they deflect to themselves from the iron just that amount of harmful action. METHOD OF TESTING WATER FOR CORROSIVENESS The first thing in testing, as is well known, is to see that the color of the water, as shown in the gauge glass, is neither black nor red. The only color * "Corrosion of Boiler Tubes in U. S. Navy," Lt. Com. Walter F. Worthington, U. S. N., Journal oj the American Society oj Naval Engineers, Vol. XII. 124 admissible is slightly dirty gray or straw color, unless the water is transparent. So long as the water is red or black, corrosion is going on, and it must immedi- ately be neutralized by freely using lime or soda, and frequently scumming and blowing off, the make-up being provided by the evaporator. The salinometer is not a very accurate instrument for determining the quantity of sea water in boiler water, but the apparatus here described gives STEAM WHALER "SHELIKOF" Owners: Pacific Whaling Co. Babcock & Wilcox Boilers, 450 Indicated Horse-power a convenient and accurate method of ascertaining the exact number of grains of chlorine per gallon in the water tested. It is based on the scheme for the volumetric determination of chlorine devised by Fr. Mohr, an emi- nent chemist, and requires one graduated bottle, one bottle of silver solution containing 4.738 grams of silver nitrate to 1000 grams of distilled water, and one bottle of chromate indicator, which is a 10 per cent, solution of pure neutral potassium chromate. To Make Test. — Fill the graduated bottle to the zero mark with the water to be tested ; add one drop of the chromate indicator ; then slowly add the silver solution; keep shaking the bottle. On nearing the full amount of silver solution required, the water will turn red for a moment, and then back to yellow again when shaken. The moment it turns red and remains red, stop adding the silver. The reading on the graduated bottle at the 125 Ejsawj Jj^.:_ I. l"J lit, ^inli»iiiii»t 126 level of the liquid will then show the amount of chlorine in grains per gallon. For example, if a permanent red color is shown when the level is midway between 150 and 200, there are 175 grains of chlorine per gallon. The principle of the process depends upon the fact that if some of this silver solution be dropped into water containing a chloride, a curdy white precipitate of chloride of silver will be formed. If there is also present in the water enough potassium chromate to give a yellow color, the white precipitate will continue to form as before, owing to the silver having a greater affinity for chlorine than for the chromic acid in the chromate. But, at the moment when all the chlorine in the sample has been con- verted, the silver will attack the yellow potas- sium chromate, and chromate of silver will be formed, which is red in color. The amount of chlorine present is, therefore, shown by the amount of silver solution required to convert it all to silver chloride, and the determination of the exact point at w^hich the chloride precipi- tate ceases to form is greatly facilitated by ob- serving when the chromate indicator turns from yellow to red. It is not necessary to add the silver solu- tion until the color becomes very red, as the delicacy of the reaction would be destroyed, but the change from yellow to yellowish red must be distinct and must not change on shaking. The sample of water to be tested should be neutral, as free acids dissolve the silver chro- mate. If it should be acid, neutralize by adding sodium carbonate. Slight alkalinity does not interfere with the reaction, but should the sample be very alkaline, it may be neutralized with nitric acid. Should it happen that the color does not change within the limits of the graduations, the sample may be tested by diluting with distilled water. For example, add three parts of distilled water to one part of the sample. If then, on testing the mixture, the color changes at 200, the number of grains per gallon in the original sample will be four times this reading, or 800 grains. The chlorine should be kept down to the least possible amount — say below 50 grains per gallon- — as the nearer the boiler water is to fresh water the safer the boilers are against corrosion. If the water is so corrosive as to be acid, blue litmus paper, which has not been allowed to become deteriorated through exposure to the atmos- Hssbs^ CiRADUATKD BoTTLE 127 128 phere (keep in a bottle with a glass stopper), will turn slightly red. If a change in color is not apparent at once, it should be allowed to remain in the solution a few minutes and then carefully dried and compared with an unused sample. Another method is to put into it a few drops of a chemical called methyl-orange. This methyl-orange gives a yellow color so long as the water is alkaline, but if turned pink, it shows that the water is acid, and therefore highly corrosive. This latter test is more sensitive than the litmus paper test, and should be used in preference. A testing kit containing the graduated bottle and the solutions referred to, also strips of blue and red litmus paper, neatly packed in a padded box, is supplied by The Babcock & Wilcox Company with all boiler installations intended for salt water service. Steam and Water Drum. Babcock & Wilcox Boiler, Details of Construction 129 CARE OF BABCOCK & WILCOX MARINE BOILERS FIRING. — The correct manner of firing boilers depends largely upon the class and quality of the fuel. Coal can be divided roughly into three classes — anthracite, or hard coal; semi-bituminous; and bituminous, or soft coal. When anthracite coal is burned it should be spread evenly over the grate and a fire of uniform thickness maintained, which may be from 3 to 8 inches, depending on the intensity of the draft and size of the fuel. When stoking, half the grate should be covered at a time. In this way, complete combustion is promoted by the fire on the bright half of the grate. Semi-bituminous coal, that is high in fixed carbon and low in volatile matter, can be fired evenly on the grate or coked just inside the fire door under the reverberatory roof, and then spread back over the incandescent fuel beyond. The coking of the coal at the front of the furnace distills off the volatile gases which burn under the furnace roof before passing among the tubes forming the heating surface. Bituminous coal, which contains a large percentage of volatile matter and a relatively small amount of fixed carbon, is best burned by stoking light and often and covering about one-quarter of the grate at a time. The fire should be from four to seven inches thick to obtain the best results. Cleaning. — The efficiency of boilers must be preserved by keeping the heating surfaces clean, both externally and internally. By means of a steam lance and a flexible hose, provided with the boilers, the soot may be almost entirely removed from the tubes, the lance being inserted through the dusting doors in the side casing. In this way the boilers may be cleaned without interfering with the stoking. On arriving in port, the boilers should be swept out, and all deposits of soot removed. When time in port will permit, the hand hole plates opposite the tubes in the vicinity of the furnaces should be removed, and the interior surfaces examined and washed out; and, if any undue accumulation of scale has taken place, it should be removed by the spoon scrapers or wire brush. Tubes have been known to blister and crack, and upon removal found to contain only an eggshell of scale thinly deposited over their entire inner surface. Had these tubes been closely examined, before removal, by means of an electric lamp or torch, a small laminated hummock of scale would have been discovered directly over the blister or crack. These small bunches are composed of flakes of scale that have become loosened from other parts of the boiler and carried with the circulation until dammed in some portion of the tube. As these bunches are loose, they may be easily dislodged by washing out with a hose. Scale burns are most likely to occur when the feed water contains sulphate of lime or when salt water is used for make-up feed. 130 If the water has a tendency to form a hard scale, such a scale should be removed with the tube scrapers provided. One thirty-second of an inch of scale is the maximum thickness that should be allowed upon the heating surface. iiii>.'JiiilliBitfi>Mir>- STEAM TUG "EDNA G" Owners: Duluth & Iron Range Railroad. Babcock & Wilcox Boilers, 550 Indicated Horse-power. Breaking Ice in Duluth Harbor Blowing Off. — Boilers should be blown through the bottom blow valves, at least twice a day, and through the surface blow valve, or scummer, once a watch. Opening these valves wide and immediately closing them is usually sufficient. Bottom blows should be used freely after the boilers have been standing with banked fires or quietly steaming. At such times blowing should be more frequently attended to, as the circulation is less active and there is more opportunity for scale-producing deposits to settle on the heating surface. Repairs. — In order to remove a tube, select a narrow ripping chisel from the tool box furnished with all installations, and slit both ends of the tube length- wise to a depth a short distance beyond the tube seat; close the expanded portions in, and, after loosening, the tube can be driven out. Care should be taken not to mar the seat in the wrought-steel header into which the tube is expanded. The process of removing and renewing tubes is the same PLUG EXTRACTOR 131 as that employed in Scotch boilers, but avoids the necessity of beading over as the ends are not exposed to the action of the flames, nor the tubes used as stays. To save time in cases of emergency, tubes may be stopped with a conical cast-iron plug supplied for the purpose. As the plug fits the tube, only a few raps with the hammer are necessary to make it tight. The large end of the plug is drilled and tapped, and may be easily withdrawn by the extractor, consisting of wrought-steel bridge, bolt and nut, furnished with the boiler. When tubes become defective, they are generally renewed as the time required is but a trifle longer than that of plugging. The expanding of the tubes is performed in the usual manner with expanders and mandrils provided. In replacing any of the short tubes, or nipples, between the headers and mud drum, or headers and steam and water drum, care should be taken that the projecting ends are swelled with the expander. All tubes and nipples should extend beyond their expanded seats one-half an inch. ^^J^ EXPANDER IX POSITION STEAM PACKET "CHARLES NELSOX" Owner: Chas. Nelson, San Francisco, Cal. Babcock & Wilcox Boilers, 850 Indratkd Horse-power 132 TESTS OF BABCOCK & WILCOX MARINE BOILERS THE object of testing a steam boiler is to determine the quantity and quality of steam it will supjjly continuously and regularly, under specified conditions ; the amount of fuel required to jjroduce that amount of steam, and sometimes sundry other facts and values. In order to ascertain these things by observation, it is necessary to exercise great care and skill, and employ the most perfect apparatus, or errors will creep in sufficient to vitiate the test and render it of no value, if not actually misleading. The principal points to be noted in a boiler test are: 1st. The type and dimensions of the boiler, including the area of heat- ing surface, steam and water space, and draft area through or between tubes. 2d. The style of grate, its area, with proportion of air space therein; height and size of funnel ; area of up-take, etc. 3d. Kind and quality of fuel ; if coal, from what mine, etc. ; percentage of refuse and percentage of moisture in fuel. The latter is a more important item than is generally understood, as in adding directly to the weight, it introduces an error in the final results directly proportioned to the per cent, of the fuel. 4th. Temperature of feed water entering boiler, and temperature of escaping gases. The temperatures of fire room and of external air may be noted, but are usually of slight importance. 5th. Pressure of steam in boiler, draft pressure in furnace, at boiler side of damper, in up-take connection with funnel, and the pressure of the blast, if any, in the ash-pit or stoke hold. 6th. Weights of feed water, of fuel and of ashes. Water meters are not reliable as an accurate measure of feed water. yth. Time of starting and of stopping test, taking care that the conditions are the same at each, as far as possible. 8th. The quality of the steam, whether "wet, " "dry" or superheated. From these data all the results can be figured, giving the economy and capacity of the boiler, and the sufficiency or insufficiency of the conditions, for obtaining the best results. For purposes of comparison with other tests, the water actually evapo- rated under the observed conditions per pound of coal and combustible and per square foot of heating surface per hour are reduced to "equivalent evaporation" from and at 212 degrees. (See page 86.) The standard boiler horse-power is equal to 34>^ pounds of water evapo- rated per hour from and at 212 degrees. The modern marine engine, however, uses only about half a boiler horse-power for each indicated horse- power, and any calculation of the former quantity is of little use for marine purposes. 133 aCRTN DECK ARRANGEMENT OF BOILERS OF U. S. S. "ALERT" TESTS OF EXPERIMENTAL MARINE BOILER BUILT BY THE BABCOCK & WILCOX COMPANY AND INSTALLED FOR EXPERI]\IENTAL PURPOSES AT THEIR WORKS THE FOLLOWING TESTS WERE MADE ON THIS BOILER UNDER THE CONDITIONS NOTED: By the late Chas. E. Emery, Ph.D., October 29TH, 1897: Anthracite egg coal; closed stoke-hold blast. By Jay M. Whitham, Mem. Am. Soc. M. E., May 7th, 1895: Pocahontas coal; closed ASH-PIT blast. By Ernest H. Peabody, Mem. Am. Soc. M. E., March 25TH, 1899: Keystone coal with mechanical stoker; natural draft. Engineer conducting test Date of test Duration of test, hours .... Heating surface: 1337 in boiler 215 in heater, sq. ft. Grate surface, sq. ft. .... Ratio of heating surface to grate surface Kind of fuel Steam pressure by gauge, average, lbs. Force of draft in inches of water, closed stoke hold . Force of draft in inches of water, closed ash-pit Force of draft in inches of water at base of funnel, average Force of draft in inches of water in furnace, average Temperature of feed water, average deg. Fahr. Temperattire of water from heater, average deg. Fahr. Temperature in upper part of closed fire room, average deg. Fahr C. E. Emery Oct. 29th, 1897 ■i Temperature of flue gases Per cent, of refuse in coal Quality of steam (by Barrus calorimeter with calibration) Average water per hour evaporated into dry steam under actual conditions, lbs. Water evaporated per pound of coal, from and at 212°, lbs Water evaporated per pound of combustible, from and at 212°, lbs Coal per sq. ft. of grate per hour, lbs. . Water evaporated per sq. ft. of heating surface per hour, under actual conditions, lbs. . Water evaporated per sq. ft. of heating surface per hour, from and at 212°, lbs. Water evaporated per sq. ft. of grate per hour, from and at 212°, lbs 7-33 1552 33-25 46.67 Lackawanna egg. Woodward Mine 200 +0.99 -0.49 +0.14 108.8 230.8 95-2 Antimony did not melt* 7.98 Dry 9619 8.36 9.08 40.29 6.20 7.21 336.72 J. M. Whitham May 7th, 1895 E. H. Peabody Mar. 25th, 1899 24 1552 38.5 40.03 Pocahontas run of mine 154 +0.98 -0-54 —0.04 66.0 147.9 By Pvrometer 607° F. 5-38 Dry 12,493 8.29 8.76 46.9 8.05 9.67 389.7 6.0 1552 45-7 33-96 Keystone run of mine 113 Natural draft -0.35 -0.15 61.3 151.0 Bismuth melted" Lead did not 12.6 Dry 5270 10. II 11.65 13-7 3-39 4.07 138.2 Antimony melts at 840° P.; lead at 625° P., and bismuth at 510° P. 135 TESTS OF A BABCOCK & WILCOX BOILER BUILT FOR THE U. S. S. "ALERT"* TESTS CONDUCTED BY A BOARD OF NAVAL ENGINEER OFFICERS CONSISTING OF LT.-COM. GEO. W. McELROY, LT. \Y. ^V. \VHITE AND LT. EMIL THEISS. The "Alert" will have two boilers placed side by side in the ship, with a passageway between them, facing an athwartship fireroom. The dimensions, over all, of the boilers are: Length at bottom of ash-pit, ii feet I inch; distance from boiler front to perpendicular from center of drum, 19^^ inches ; length at top from back end to center of drum, 10 feet s-yi inches ; width of boiler, 8 feet 9 inches; height from bottom of ash-pit to center of drum, 10 feet 8)'2 inches. Heating surface, outside of tubes, square feet .... 2012 Heating surface in boxes, square feet 93 Heating surface in drum, square feet . .... 20 Total heating surface 2125 Grate surface (length of grate, 6 feet 4 inches) square feet . . 48 Ratio heating surface to grate surface 44 : i Air heater: Number of tubes (each 3 inches diameter and 6 feet long) . 102 Heating surface in tubes, square feet 481 Area through tubes, square feet ... .... 4.3 Least area l)et\vcen tubes for up-take gases, square feet . . 7.25 Smoke pipe: Diameter, feet and inches 3-6 Height, feet 48 Boiler: Weight of boiler, dry-weighed on car, complete, pounds . . 46488 Total weight of boiler and water, pounds 54638 The weight of water necessary to fill this boiler to 5 inches in gauge glass (which is at the middle of the driun), is 8833 pounds, or 8150 pounds for same level at temperature due to boiling water under 225 pounds pressure. DESCRIPTION OF TESTS Four separate tests were made, on April 11, 12, 13 and 14, 1899. The first was with cold air, closed ash-pit draft, and a steam jet in the smoke pipe. This test was intended to demonstrate the performance, under the con- ditions stated, of the boiler with the maximum consumption of coal that it is expected to reach in naval practice. The second test was with open ash-pit, a steam jet being used in the chimney to produce a partial vacuum about equivalent to that due to the height of smoke pipe as on the ship, viz., about 0.45 inch of water. The third was with heated air, closed ash-pit draft, and a steam jet in the * Extracts from the annual report for 1899 of Admiral Geo. W. Melville, then Engineer-in- chicf of the United vStatcs Navy. 136 chimney. The blower drew the air through the heater tubes and discharged it into the back of the ash-pit. The conditions as to draft, method of firing, and temperature of feed were as nearly as possible the same as in test No. i , the object being to establish the effect due to the heating of the air. In all the three preceding tests Cumberland coal was used. During the first and the greater part of the second test it was George's Creek coal. During the latter part of the second test, and throughout the third test, another shipment of coal, also Cumberland, was used. This last coal contained less slack and less surface moisture than the first, but all was of excellent and presumably of very similar quality. The fourth test was with cold air, closed ash-pit draft, and a steam jet in the chimney, and was undertaken to show the efficiency of the boiler using hard coal under moderately strong forced draft. Attention is especially directed to the comparative results of tests made April 13 in presence of the Board, and on April 19 by the firm. These two tests were made under nearly identical conditions as to draft, temperature of feed, and method of firing, except that during the test of April 13 the air heater was in use, while on April 19 it was not, and would seem to show that with the ratio of grate to heating surface, and the circulation of gases secured in the boiler under test, the up-take gases escape at so moderate a temperature that the air heater is of little value. The data of the tests, bearing on this point, are given in the table on the following page. The results of the parallel tests, with and without air heaters in use, made by the Board on April 1 1 and on April 13, are somewhat vitiated by the fact that the coal used was not from the same shipment in the two cases; and, while from the same coal region, and presumably of very similar heating value, the first lot contained about 4.09 per cent, of surface moisture, and was composed of nearly 75 per cent, slack, while the second lot contained 2.77 per cent, of surface moisture, and contained much less slack — about 50 per cent. The following experiment, made April 22, in the presence of Lieut, (then Chief Engineer) G. W. McElroy, United Spates Navy, gives the time required for raising steam under the conditions stated. Fires were started with wood and oily waste in front. About one-half shovel- ful of kerosene was thrown on just after lighting the fires. Soft coal was used toward the end. The boiler was at atmospheric temperature when fires were lighted, the water at the temperature of 54° F. Its height in the gauge glass on starting fires was 1^4 inches. Almost immediately after the fires were started the circulation of the water began, as evidenced by the temperature of the different parts of the boiler. RECORD OF RAISING STEAM Lighted fire. 1J4 inches water in boiler gauge glass. Natural draft Began to make steam. No pressure on steam gauge 5 pounds pressure on steam gauge 10 pounds pressure on steam gauge 20 pounds pressure on steam gauge 25 pounds pressure on steam gauge 40 pounds pressure on steam gauge 137 II.3I 11.42 1 144' 2 1 1 45 ii.463i 11.47 11.48^ ARRANGEMENT OF BABCOCK & WILCOX BOILERS IN LARGE LAKE CARGO STEAMERS 138 c 00 >-< M q Tt cf i^ ri 0,0 00 O O Om^ " « CO to t-oo o o 13'-''U:73 >qqoi mi/)n 2 J rt 5 'H d r^ o M i' l' a Pi S3 •^oo .OtdvOO'OOt'-r^'^n'vc X in aS too •-• f " ro ■^ 'ti- t; O Ov !■! ro n N H 3 ro o O M S -OO » « gNOOMOOO MOO 'to L^ doo'ddiooorofodi-^ M" ^ r- t^ C) o M M ■-' O I-OO o oxi a<; N I + : -O t^OO "i p-c M,x„Tio; OsnO ro pi J, ■ ■ « V- u J3 QIC HO I 1 + O 00 fs f *0 ^ t^ l/^O M Tf M lO N O 00 i-t M M I J too N M M w O, . I I 00 sO O t^ I O i-i O On 'O 1 O O O ro 1/1 IT) M O lOOO M l/l rj f>7 O O 1^ d ri d d q t~- ro I~ o, rj- o fovd lA d d NO O O r^GO 0> o O O CO n M fO ro fO 00 00 ►-■ 1 *o p! o 4 w "Si- •- p. bo o *" CO -^13 o •-« " C O t^ t 'J' c S '"' *^ h5 O O «^ 00 i-i -t f ) l*^ i-H 00 N w cs 00 OoO ro t-^ ■^o ■^ cJ c^ Oi d O 00 ro C> -t O* O rood lo t^ 0\ .E C rt m'^O m " w • O M 00 M ■ O ro O ^ N t^ M 00 O. »o o 1 1 M d\ d ffi ^ Q v-^B e " t^ o I I "^ o o d\ t^od d O O (N M M 1- -^oo ; a o ^"^-isl I -2 J goimE-fe Q m in ^' -IT ^ K^ »^' ^fC J oa o-m ^ tf 139 5iH 52% 53 535^ 54?^ 55H RECORD OF RAISING STEAM— Continued 49 /i 50 pounds pressure on steam gauge 51 65 pounds pressure on steam gauge. 4J 2 inches water in boiler gauge glass- Put on blower 75 pounds pressure on steam gauge 100 pounds pressure on steam gauge 105 pounds pressure on steam gauge 125 pounds pressure on steam gauge 150 pounds pressure on steam gauge 175 pounds pressure on steam gauge 56^4 200 pounds pressure on steam gauge 57/4 225 pounds pressure on steam gauge, s^^incnes water in boilergauge glass. Safety valve blowing. Stopped blower The table contains the calculated results and final averages. The evapora- tion has been figured out on the basis of dry coal and combustible consumed, and water evaporated into steam of the calculated quality. On the completion of the tests the boiler was thoroughly examined inside and outside. The grate bars and bearers had not suffered the least injury, nor did the fire- brick back, or the fire-brick baffles supported upon the row of 4-inch tubes over the furnace, show signs of distress. The entire outer casing plates opposite the tubes were removed on one side and the magnesia and fire-brick lining taken down, exposing the tubes and making possible an examination of the sectional vertical baffles. These, as well as the inclined deflector in the space above the tubes, were found in perfect condition. The edges were sharp and no warping was noticeable. The 4-inch tubes imme- diately above the furnace were perfectly straight. Generally speaking, the tests conducted must be regarded as most satis- factory. The boiler did its work under natural and under forced draft with good economy and without distress. The comparatively low temperature of the up- take gases during all the tests both with and without the air heater in use seems to indicate that the air heater is not a necessity in combination with a boiler of the design in question, and cannot be considered a desirable adjunct except possibly when working at very high rates of combustion. Ore Docks at Two Harbors, Mi.\.n. 140 m cy > *k5 o 2 "" o o al very ed dur- blower uously •a a 3 O down 83 tons n ore. orward ■; in. M i^O o c c a g " o S c a CO f3 3 & S & is So- C (NO 1'? Lake Huron, c poor, fires clea ing test and running conti (U 4J 3 M 3-g 13 pa & oO I ST "C (^ o rt 3 c J J J J ■ " ■ J ' ^ DO ^4 « V- C 6 ^ o C " to P-- 3 K o f2i« ^'m ^y. o rt rt' rt nl C! 'f ffi ._^ w o Q Q CL, , ^ ^ >-\ 1-^ i-A I— 1 w w w fr, DO CO CO ^o sai'IV " -^ to 00 (-1 ro spss3^\ JO paadg [? f^ fo ro " [^ ^ « " ^ o. Cv ro to 00 rO to T -T a^BJO o> M " 00 t 0\ vO ■0 r^ •;^ -bg J3d -J -H -I [3^ ""^ M [^ Ov O M « " ro N r^ lO to I^ M M >-H Oi •d -H -I I^^^oi o o f O t^ '^ -0 CO CO to •t -t to 00 >-* ^ '-' *-• '-' "- "^ 1-H >- '-' •^ Oi r^ ro ri -(- to -o xO o o Ol o « o> o> pUB UIOJJ *"* <> in ^ 'O C^ f-l ro M -o suou o o o vO t^ rl- M CO ^•a -ipuoo t- t^ r^ o> Oi 00 00 00 J IBnjov • " ■ AlUQ -Sua 0' ^ uiBjNi -d -H -I rO fO fO j3d -jj^ jod j3;bj\\ — M *^ 1 iH O O •3U3 UIBJ^ - io -f ■ CO O 'f to 00 rt 3 d o o t^ o M l^lOX o t 00 CO vO to ffi n r] M tH "-* 04 o o -r M -t CO to d H I CO I^ o t^ t^ t^ t^ vO 3 o aoj CN a oO o 1^ ro c^ t fO o U O] o >o O O O rO o M M N p;oj. o lO o O t^ ro w Tf fO 00 fO ^ "5 M -i s:}nuii,v -isd -SAs-g h; N O ■o to to r-- CO r- ■i- ro 00 Ci r^ •^ r^ ■^ r^ r^ t^ t-- 00 saqouj o CO to 0. d Ov .0 uinnoB^ " rl rl ~> 't N o Tl- rO ro -O In " CN o CO M •03-y M C\ to CO •t o o> 0. j3 •d 'T "I o o o ^ •t " (N t^ CO Cv r-- g- •oay CO fO •d 'I PZ "I "5 ~5 ,, -J, ,^ C\ ^ N 00 ro to -3 ■39^ ,_:. ui M Ov ^ to t^ 00 r^ •d 'I ^si UI .o to •^ o Ov O to 10 to to r> M ,, C\ ■<*• f«^ ro N M sjajiog iv o o C\ o -I- -t -1- t C\ 00 00 10 fO SJnojj ;s3x JO uoi;BJnQ -t o> ro ■o o " « 2! !^ •^ P) o o CO 0. o , Ov O fo o to 10 to o to OO ^_, '-' >-< )-• M ot ^H O +J o O 3 3 a M 3 < ti 3 < a (U m c c 3 3 V c 3 1—1 d Q >. >. >. >^ >. >- >> o_ -U t; o 4-3 V u u O o c c O u o u 4-1 J2 Jd J=: a> u c c c c ^> 'S 4-3 'c 'c 0) tSJ o o 3 a a; U U a 3 a e 3 o 3 3 0) 3 ^ rt hJ 141 m^isissss^ o m < o m cq -_i..i- .^L 142 TESTS OF MACHINERY OF S. S. "PENNSYLVANIA" At the request of Capt. A. B. Wolvin, of Duluth, the Babcock & Wilcox Company installed its testing apparatus on board the Minnesota Steamship Company's new steamer "Pennsylvania "* for the purpose of making a series of tests of that steamer's machinery. Advantage was also taken of this opportunity by the Navy Department to secure exact data regarding the economy of the boilers, the steam con- sumption of the main engine and auxiliary machinery, and the working of the mechanical stoker with which the ship was fitted. Accordingly, Lieutenants B. C. Bryan and W. W. White were detailed by the Bureau of Steam Engineering to make a trip with the ship and conduct the trials. The results obtained were published in vol. xi. (1899), part 3, of the Jour7ial of the American Society of Naval Engineers, from which we quote the following : "The main propelling engine is of the vertical, direct-acting, inverted, jet- condensing quadruple-expansion type, designed for a maximum horse-power of about 2000. Number of cylinders, unjacketed 4 C High-pressure 15M Diameter of cylinders, j First intermediate-pressure . . 23^ in inches j Second intermediate-pressure . . 36 J^ y Low-pressure 56 Stroke, inches 40 Diarheter of piston rods, inches 4% "Steam is supplied by two boilers of the Babcock & Wilcox water-tube marine type, built for a pressure of 250 pounds. Each boiler is 9 feet 3 inches long, 12 feet 6 inches wide, and 16 feet 8 inches high, containing 3000 square feet of heating surface and suitable for 65 square feet of grate surface. Weight of boilers, dry, pounds 145,860 Weight of water contained, pounds 33.492 Total weight of boilers and water, pounds .... 179,352 "All steam-generating tubes are 2 inches in diameter, No. 10 B. W. G. in thickness and 7 feet 3 inches long, the connecting tubes being 4 inches in diameter and No. 6 B. W. G. in thickness. The sides of the boilers are formed by 2-inch tubes inclined the same as the generating tubes, but placed one above the other and expanded into straight manifolds or corner boxes. "Three mechanical underfed stokers are fitted to each boiler. These were installed by the American Stoker Company. "The particular coal handled on these trials was from the Essen mine, in western Pennsylvania. It contained a large percentage of refuse, and therefore * The name of this vessel has since been changed to " Mataafa. " 143 afforded an excellent opportunity of illustrating any superiority in stoking which a mechanical device would give over hand firing. A test of a sample of the coal used gave, by a Mahler bomb calorimeter, 1 1 ,790 B. T. U. per pound of dry coal. "In all, eight tests of the main engine were made. No. i, No. 2, and No. 5 are similar, and representative of the usual power developed under ordinary steaming conditions of the vessel. Test No. 3 was made with almost maximtim high-pressure cut-off; test No. 4, cutting off very nearly as short as the high- pressure valve gear would permit. "Tests No. 6 (a, b, c) were undertaken with the sole aim of ascertaining the economy of the main engine when working tmder reduced boiler pressures, no account of the coal used being recorded. "The results of these tests are not strictly comparable, on account of the irregular operation of the air pump, causing, as will be seen from an inspection of the tables, considerable variation in the vacuum obtained on the different tests. A more satisfactory comparison would have been possible had the vacuum carried been about the same at all times. "Previous to beginning the above tests the dead plates of the furnace were thoroughly cleaned of clinker. The same operation was repeated about an hour before each, test ended, particular attention being given to have the fires, as nearly as could be judged by the eye, in the same condition at both the beginning and the end. Each tost was begun and finished with the stoker hoppers entirely filled; coal fired during the interval covered by the test was accurately weighed on a platform scale. " During the tests all water fed to the boilers was delivered by the air pump through a 4-inch pipe connection from the overboard discharge of the (jet) condenser, into the upper of two tanks in the engine room, which latter were specially installed for the tests. The upper tank was mounted upon platform scales, and water flowing into it could be regulated or shut off, as desired, by means of a valve. Each tank of water, after weighing, was dropped In' gravity to the lower tank, from which a suction i)ipc of about 8 feet in length led to the feed pump. "All tests began with the lower or feeding tank full, and ended in the same way. "A Barrus throttling calorimeter attached to the main steam pipe near the high-pressure cylinder was used to determine the quality of steam supplied by the boilers, and readings of the upper and lower thermometers were recorded. "The moisture in the steam, as figured, after making due allowance for con- densation in the instrument, is so infinitesimal as to be entirely negligible in the final results. The assumption has been made, therefore, that dry steam was furnished during all the tests. "The method adopted to determine the amount of steam used by the auxiliary machinery was to condense the exhaust steam therefrom and weigh the resultant water. This condensation was accomplished by means of a cylindrical exhaust feed-water heater, of the surface condenser type, containing thirty-eight 2-inch tubes 9 feet long. The feed water on its path to the boilers passed through these tubes and condensed the exhaust steam from the auxiliaries, which was directed into the shell, and at the same time elevated its own temperature pro- 144 o o cs M rro '-<'-«o>-*'^owm O w^ O M -t CO 00 O O i'^ O 0\ M C> «0 M ' oc 1*0 -t OO ■ r^ O O O to ^l^ t^ O ■rf -t *TO I- >-. GO M (D ^ r^ t>- '^ ro i>^r-ioor-ooc>f CC lO lO r^ 6 »o 2^ t^ m " rfco lO J, M vOO n >oo „ in •:f -t N MOO C-) O m •N f^l 00 M lO Os oo 'O -t CO '~ " "* 'Jl ro O 'O -f 'f '~! t^ i-^ q\ -T o o I- £ , MS t;; c; oj ^ >. c o oi ■a o c ?i ~ -ro w I^ro-tOro>-' rOt^iOMoo M r-TiOM o^ ! 1-0 O POO M — aj 3 C 01 O'r.'^J N lOO t^ T I^ (^ 00 t^ 0\0 '^ "^ oj 1 •- M o 'OO o ■iO I^ M ro O in PO O ro ^ O -J- lO O ro I ^ ►H KH O f ° 3 cd 2 "> S:^. o & o J-Q '" O C ^ - .^ -5 "J „, — ■«» C S m « O « C'C ft'-v-'^ »— "^■^ O ^ "i O '^'^ « ft s V- '"I o rt ^ t , Tl O ft u >. „ o aj o CJ — . .SB ually steam ds . mois o ■S.s 3 . o— c o a! nl 3 . ft c 'SSftg o "rt " o f^o^ 1^^^^ Q ' — ■ — ' a) o _, •C u ri< »< s C WAh u rt Q o 145 portionately. In order to reduce the temperature of the drain from the feed heater, it was led to a coil contained within a barrel. A stream of cooling water ran into the barrel and overflowed into the bilge. Mounted upon platform scales was another barrel which received, by gravity, the condensed exhaust steam from the auxiliaries. As soon as the weighing barrel was filled the inflow was momen- tarily stopped, the weight taken, and then the condensed water rapidly discharged into the bilge. "On May 28th, three special tests were run, with the view of fixing the steam consumption of the fire-room blower and air pump, and incidentally the total steam necessary to operate the several auxiliary pumps and the steering engine, which were in use during all the tests. The power developed by the main engine, and the average weight of coal burned were about as shown in test No. i . STEAM CONSUMPTION OF AUXILIARY MACHINERY Auxiliary Sleam Consumed per Hour (Pounds) Air pump 721 715 828 613 Feed pump . 487 468 595 350 Bilge pump 275 275 320 240 Water-service pump 146 154 156 150 Auxiliary pump . 330 Starboard dynamo 480 480 Port dynamo 671 Steering engine . 125 125 125 125 Fire-room blower 622 692 2909 725 550 Total . 3377 3229 2028 "To determine the amount of steam used in operating the stokers, the exhaust from one was led into a barrel containing a previously weighed quantity of water, and there condensed. Two tests, similarly made, gave 22.5 and i-x^."] pounds, respectively, or an average of 23.1 pounds, as the hourly consumption. For all stokers the steam used per hour would, therefore, amount to 138.6 pounds. " The cost of operating all stokers and the blower is found to be 4.29 jjcr cent, of the total steam generated. By reason of the blower exhaust passing through the feed heater, however, the actual net cost of the stoker installation is equiva- lent only to 1.68 per cent, of the steam made. " Attention of the reader is particularly called to the high evaporation obtained from and at 212° per pound of coal, the average result of five tests being 8.86, which is especially g.ood when it is remembered that the coal burned contained only 11,790 B. T. U. per pound. The average efficiency of the boiler is therefore 72.6 per cent. Again, the coal consumption per indicated horse-power would have been materially reduced had it been possible to maintain a better vacuum, the highest reading recorded being only 24.35 inches, while the average was only 23.5 inches. 146 TESTS OF MACHINERY OF S. S. "ALEXANDER McDOUGALL"* Under direction of the Bureau and by the courtesy of the officials of the Minnesota Steamship Co., two tests were made by Lieuts. B. C. Bryan and W. W. White, U. S. N., of this Bureau, of the' main machinery of the steamer "Alexander McDougall," at present the largest whaleback in service on the Great Lakes. The main engine was designed for a maximum horse-power of about 2500 and is similar in arrangement and all essential features to the engine of the "Pennsylvania." The auxiliary machinery, however, differs from that of the "Pennsylvania," in that the air, water service (cooler), and bilge pumps are attached to the low- pressure cross-head of the main engine; the feed pump (Deane), is independent, duplex, of the horizontal compound tandem-plunger type, having steam cylinders of 8 and 12 inches, respectively, with water cylinders of 5 inches, and a common stroke of 10 inches. Much of the other auxiliary machinery is practically the same on both ships. Data of Main Engine Diameter of cylinders, inches (all rods 53<4-inch diameter) Stroke inches Net piston areas, square inches Ratios of net piston areas Clearances, per cent. High- pressure First Inter- Second In- mediate- termediate- pressure pressure 19 28K 43 40 40 40 272.7 627.12 1441.38 1:12.51 1:5.42 1:2.36 15 II 10 Low- pressure 66 40 3410-38 I 9 Steam is supplied by two boilers of the Babcock & Wilcox marine water- tubular type, built for a pressure of 250 pounds, containing 7000 square feet of heating and 128.8 square feet of grate surface. Two small one-cylinder (5 by 5) blowers, one for each boiler, with an inlet through heaters in the up-take and delivering at the back of the ash-pits, supply the necessary air under forced draft for combustion of the fuel, which latter is hand-fired. Two tests were made on the down trip, one on Lake Superior and the other on Lake Huron. The vessel was loaded with a cargo of 6407 tons (2240 pounds each) of iron ore, and had in tow the barge "Constitution, " laden with 5164 tons of the same material. The method of weighing the total water fed to the boilers, and ascertaining the steam used by the auxiliaries was, substantially, the same as in the tests of the machinery of the "Pennsylvania." A summary of results obtained appears on page 151. At the beginning of the test on July 21, the following auxiliary machinery was in operation : Feed pump, steam-steering engine and both fire-room blowers. By reason of the feed-water heater being entirely too small, excessive back pressure resulted, and the fire-room blowers were stopped (in use one and one-fifth hours) after it became evident that steam could be readily and easily maintained at the * Extract from the annual report for 1899 of Admiral Geo. W. Melville, then Engineer-in- chief, U. S. N. 147 1 4^ SUMMARY OF TRIALS— S. S. "ALEX. McDOUGALL' Date of trial, 1899 Duration of trial, hours .... Speed of vessel, miles .... Draft of vessel during trial, forward, feet Draft of vessel during trial, aft, feet Revolutions of engines .... Piston speed, feet per minute . ( Boiler . I At engine Pressures per gauge . <^ First receiver Second receiver I Third receiver Vacuum in condenser, inches of mercury Opening of throttle Steam cut-off in fractions of stroke . i High-pressure J F"ir: Mean pressure in ders . Indicated horse-power irst intermediate-pressure Second intermediate-pressure Low-pressure Nominal ratio of expansion [ High-pressure I First intermediate-pressure ylin- ■{ Second intermediate-pressure j Low-pressure I Equivalent reduced to low-pressure f High -pressure I First intermediate-pressure -l Second intermediate-pressure Per cent, of total indi- cated horse-power de- veloped in each cylin- der .... Low-pressure I Total i High -pressure ) First intermediate-pressure j Second intermediate-pressure ' Low-pressure f Injection .... Temperature, in degrees j Hot- well .... Fahrenheit . . j Feed water after passing heater L Escaping gases at base of smoke pipe Double strokes of feed pump . Revolutions of the blow- j Port ers . . . . ] Starboard Air pressure, boiler ash-pits, inches of water Kind of coal Total amount of coal consumed, pounds Moisture in coal, per cent. Dry coal consumed, pounds Total refuse in coal, pounds Total combustible consumed, pounds Quality of steam Weighed water pumped to boilers, pounds Water evaporated per pound of dry coal, boiler conditions, pounds Water evaporated per pound of combustible, boiler conditions, pound; Equivalent evaporation, per pound of dry coal from and at 212° Equivalent evaporation, per pound of combustible, from and at 212 Dry coal burned per hour per square foot of grate surface, pounds Total steam used by main engine, pounds Total steam used by auxiliary machinery, as weighed, pounds . Steam used by main engine per hour, per indicated horse-power de veloped, pounds Total steam used (all machinery in use) per hour, per indicated horse power developed by main engine Dry coal used per hour per indicated horse-power to generate steam necessary to run main engine only, pounds Dry coal used per hour per indicated horse-power, developed by main engine, to generate steam required to operate all machinery in use. July 21 10 8.83 i7-«3 18.00 754 502.7 247.8 245 96.8 33-1 2.09 22.35 Wide •53 •56 •63 .66 20.04 93-4 36.1 15-5 6.85 27-57 388.15 345-29 342.85 357-00 1433-29 27.08 24.09 23.92 24.91 46 117 170.6 543-6 26.1 t t 27200 5 25840 2967 22873 Dry 223996 8.67 9-79 9-58 10.82 20.06 207764 16232 14-50 15-63 1.67 1.80 July 23 6 9-75 17-83 18.00 81.7 544-7 244 240.7 107.5 35.2 3-2 22.4 Wide .685 .625 .655 -725 16.39 100.90 44-56 18.88 8.31 32.60 456.94 459-55 452.52 466.94 1835.95 24.89 25-03 24-65 25-43 64 115 157-8 526 29.7 391 31^*3 -25 X 19500 5 18525 1710 16815 Dry 165980 8.96 9.87 10.02 11.03 23-97 157346 8634 14.28 15-07 1-59 1.68 * Not in operation. f Natural Draft, t Run of Mine, Pittsburg bituminous. 149 usual pressure without their aid. The average hourly weight of condensed ex- haust steam collected during five hours of the test, with the feed pump and steering engine only in use, amounted to 1685.4 pounds. For the purpose of fixing the steam economy of the feed pump during the last two and one-fourth hours of the test, the steam-steering engine was thrown out and the ship steered by hand. Under the latter conditions, an average of 1 174.7 pounds of condensed exhaust steam per hour resulted. During the entire test on July 23, the only auxiliary machinery in operation was the feed pump and fire-room blowers. U, S. BATTLESHIP ■' NEW HAMPSHIRE " Babcock & Wilcox Boilers. 17,'200 Indicated Horse-power 150 TESTS OF A BABCOCK & WILCOX BOILER BUILT FOR THE U. S. S. "CINCINNATI"* In the annual report of the Chief of the Bureau of Steam Engineering for 1900 there is published a report of tests made on one of eight new boilers built by the Babcock & Wilcox Company for the "Cincinnati, " by a board composed of Lieutenant-Commander A. B. Willits and Lieutenant B. C. Bryan, U. S, N. These tests were made June 15 to 22, 1900, at the works of the builders, Elizabeth- port, N. J., and the following synopsis includes all but the detailed tabulations from which the important results given were deduced. DESCRIPTION OF BOILER AND APPURTENANCES The boiler is of the Babcock & Wilcox new marine type, composed entirely of wrought steel, the point of difference between it and the older type of this make of boiler being in the arrangement of baffle plates (as shown in the sectional view on the following page) which compel the products of combustion to pass three times across the tubes before entering the up-take. The small tubes are 2 inches outside diameter, while the bottom tube in each section or element, is 4 inches outside diameter. The total heating surface is 2640 square feet. The grate is an undivided area of 63.25 square feet, and is fired through four properly spaced doors. BOILER DATA Kind of boiler, Babcock & Wilcox— " Alert " type. Diameter of top drum, 42 inches, inside. Length of top drum, 12 feet. Tubes: total number, 565; length, 8 feet (525, 2 inches outside diameter, and 40, 4 inches outside diameter). Grate surface: length, 6 feet 8)4 inches; width, 9 feet ^}4 inches; area, 63.25. Grate surface reduced in tests Nos. 5 and 6, to 5 feet 6 inches ; 52 square feet area. Heating surface: area, 2640 square feet; ratio to grate, 41.74:1. Per cent, water- heating surface, 100. Grate bars: kind, fixed. Smoke pipe: area, 7.876 feet; height, 48 feet above grate ; ratio to grate, i : 8.03. Weight of boiler and all fittings except up-takes and smoke pipe : Without water, pounds 53304 Water, 5 inches in glass; steam at 215 pounds, pounds . . 9498 Total with water, pounds 62802 Total weight per square foot of grate surface, pounds . . 992.9 Total weight per square foot of heating surface, pounds . . 23.79 Blower: kind, 60-inch Sturtevant, driven by belt from shop engines. Area of blower inlet, 9.62 square feet; outlet, 6.89 square feet. Feed water: kind, feed water heated by steam jet. Air heater: kind, two-pass; 3-inch tubes. Area of surface, 495 square feet. Feed pumps: kind, Worthington duplex; diameters of cylinders, 7^ and 4 inches ; 6-inch stroke. Other boiler appurtenances : steam jet. The boiler was erected in a wooden structure built especially for the test and having the following dimensions: Length, 29 feet 2 inches; width, 17 feet 2^ * Extracts from the Journal of the American Society of Naval Engineers, volume xii. (1900). 151 I,'. O M < ? Q o H o < pq ^ 'J o d u oa . u I inches; height, 21 feet. This was made as nearly air-tight as possible, but contained several windows that could be opened or closed to regulate the amount of draft pressure. The blower was driven by belting from the main shop engines and ran continually. An air heater was built in the up-take by means of which the waste gases imparted heat to the air on its passage to the ash-pit. This heater could be placed in and out of service at will by the use of a by-pass flue. 'CIXCIXXATI'S' BOILER— B. & W. "ALERT" DESIGN. PATH OF GASES SECTION SHOWING DESCRIPTION AND OBJECT OF TESTS Seven tests were made in all. Six of these consisted of three pairs, in which the tests of each pair were made under similar conditions in every way except that of using the air heater, one being with and the other being without this heater, in order to define the econom}- due to its use. The last or seventh test was for inaximum capacity, and was made without the air heater and with the full grate. Two pairs of tests, one at a consumption of about 20 pounds of coal and the other at about 35 pounds of coal per square foot of grate per hour, were made with the full grate surface in use. These tests will be found in tables of results numbered i, 2-H, 3-H, 4, the letter H signifying that the air heater was in use during the tests. The grate surface was then reduced to 52 square feet, by a 153 June 19, 1900, — Without air heater, full grate. Coal per square foot of grate per hour, 35.08 pounds. Water per square foot of heating surface, from and at 212°, 8.75 POUNDS. June 20, igco. — Without air heater, reduced grate. Co.\L per square foot of grate per HOUR, 50.38 pounds. Water per squarb foot of heating surface, from and at 212°, 10.07 POUNDS. Al. — Aluminum melts at Sb. — Antimony melts at Zn. — Zinc melts at Pb. — Lead melts at 1160' F. 840° F. 7So^ F. 02S" F. June 22, 1900. — Without air heater, full grate. Coal per square foot of grate per hour, 59.2 pounds. Water per square foot of heating surface, from and at 212°, 13.67 pounds. June 25, uyoo. — Without air heater, full grate. Coal per square foot of grate per hour, 20. 18 pounds. Water per square foot of heating surface, from and at 212"^, 5.42 pounds. TEMPERATURE OF GASES PASSIXG THROUGH BOILER AS SHOWN BY MELTIXG POINT OF METALS— TESTS OF ■•CINCINNATI" BOILER 154 course and a half of bricks, seven courses in height, at the back of the furnace, and tests Nos. 5 and 6-H were made, burning about 50 pounds of coal per square foot of grate per hour. The bricks were then removed from the furnace and test No. 7 was made, burning nearly 60 pounds of coal per square foot of grate per hour. The data and results of these tests will be found in the table on pages 158 and 159. COAL AND FIRING The fuel used was Pocahontas, Flat Top, coal. It contained considerable slate and clinkered badly. On tests Nos. i and 2-H run-of-mine coal was used; on tests Nos. 3-H, 4, 5, and 6-H the coal was screened, using a screen with a i-inch mesh. On test No. 7 the screenings from the former tests were run over a f-inch mesh screen, and the coal thus screened was mixed with the screened coal used in other tests. The firing was good and very regular. Two alternate doors were fired in rapid succession. The other two sections of fires, in wake of the other two doors, were sliced through the slicing door, and then leveled with a hoe, and then coaled, the average time between coalings of the same two furnaces being from eight to ten minutes. The furnace doors were open about twenty-five seconds when coaling and about ten seconds in leveling. The coal made com- paratively little smoke except when firing or working fires. The data in regard to smoke was taken by using Ringelmann charts. DESCRIPTION OF APPARATUS The water was weighed in two tanks, each supported on a platform scale and run into a third tank below, from which the feed pumps drew water. All pipes were above ground and in plain sight, and wherever connected to other piping or boilers, plugs were left out of T connections to show that there was no leakage. The gross and tare weights of each tank were taken, and the temperature was taken at the lower tank just as each upper tank drained into it. The feed water was heated by steam injection before entering the weighing tanks. The coal was weighed in barrows on platform scales in the fire room and dumped on the floor. The time was taken when each lot of barrows was fired. A sample shovelful of coal was taken from each lot of barrows and thrown into a barrel, and from this, mixed and quartered, the final samples for analyses, calorimeter and moisture determinations were taken. The gases for analyses were drawn from near the center of the base of smoke pipe by means of a pipe inserted therein connected with an inspirator and a small Orsat instrument. All draft pressures were taken outside the building, pipes being led there from the different places where pressure determinations were required. Temperatures were taken at the back and front of the up-take just above the heater; in front by a mercurial pyrometer, and at the back by a metallic pyro- meter. When the air heater was used the temperature was taken in addition just below the heater by means of a mercurial pyrometer. The moisture in the steam was determined by a Barrus universal calorimeter. The steam was found practically dry in all cases. The steam was partly used in the shop and partly blown off into the atmosphere, the pressure being controlled by regulating a small stop valve by hand. Experiments to show the heat of the gases at various points were made by 155 156 noting the points at which different metals melted. A small piece of metal was wired to a j^iccc of >^-inch pipe, and pushed in carefully through the dust doors at the side of casing to about the middle of the boiler; by noting where such metal would melt, and again introducing a piece of the same metal at another hole farther along in the path of the gases until a position was reached when the metal would not melt, and by the use of various metals with known melting points, the temperature of the gases was determined and is plotted on the diagrams on page 154. Before making test No. 6-H, on June 21st, all water was drained from the boiler and the contents of boiler noted for each i-inch mark of the water gauge glass, with the following results : WEIGHT OF WATER CONTAINED IN BOILER Temperature of Water, 72 Degrees Fahrenheit Height of Wate.- in Gauge Inches Total Water Pounds Difference Height of Water in Gauge Inches Total Water Pounds Difference I 2 3 4 9312 9498 9662 9912 IOI37 186 164 250 225 5 6 7 8 10368 10672 10943 III75 231 304 271 232 Fires were started in the boilers with light wood, and blower in use, at 9:40 A.M. Temperature of water in boiler, "2 degrees; height in gauge glass, i inch. The following is a record of the time required to raise steam, to 215 pounds pressure from cold water : RECORD OF RAISING STEAM Time Time Steam Pressure Pounds : Steam Pressure Pounds By Watch Elapsed ' By Watch Elapsed 9:40 Fires started 1 1 mins. sees. 125 9 ^^ Di 9:45 5 mms. sees. vSteam formed 9 51 :io 11 mms. 10 sees. 135 9:46:30 6 mins. 30 sec;;.. 25 9 51:15 II mms. 15 sees. 145 9:47:30 7 mms. 30 sees. 35 9 51:30 1 1 mms. 30 sees. 155 9:48 8 mins. sees. 45 9 51:40 1 1 mms. 40 sees. 165 9:48:30 8 mins. 30 sees. 55 9 51:55 1 1 mms. 55 sees. 175 9:49 9 mms. sees. 65 9 52:10 12 mms. I osees. 185 9:49:30 9 mms. 30 sees. 75 9 52 :20 12 mins. 20 sees. 195 9--50 10 mms. osees 85 9 52 :30 12 mins. 30 sees. 205 9:50:30 10 mins. 30 sees 95 9 52:40 12 mms. 40 sees. 215 9:50:45 10 mms. 45 sees 115 An examination of the boiler after this test showed no injury or change in its condition in any respect. In addition to the tests made for the Navy Department, three tests were made for The Babcock & Wilcox Company by Air. E. H. Peabody, Mem. Am. Soc. AI. E. The data and results of these tests are included with the others in the following table : 157 < l-H o o \n *' •n t 00 r^ 4) 4) «n m 00 00 ui a ; t^ -f r*5 '■ '• '? .y c T -: m -1 -^ 6 riGP^ • " r r 1' • • rO r~ + t~ M fe 5i ' f-ro d pi j; m MO -J- c^ " " -^o ti d S • 0. 1 1 1 • • t ^ rO Tt M pj M PI m -t CO ^ < p. w m m T i-i < s ? is3 ^^ 0000 4)'S m . in ►- c ; ; : ■* -i C r- p; m tn ^ o o 4jo t: oi o -^M 1 ^cp. :g r I' ■ ■ ■ -T . . ri-t 0> • a • • Ov I-. 10 j£ " m p) rood t_ u ~3 000 t^ So mi-00 -T '-' < p. WCO CO .- 4J „, CO! '^ '7 OMO Is ? ffi . CMo q o ! ! ' '^ in in 5i CO 1 Su-^-* • d " f . -r . • d t " c.- no t^o 0. sd t-- w •SI ' • " • • - « « 3 E 00c rO -> < 0, ^. OC PI N o! l-i '^i T N 00 -t CvoO —t' - -3 00 m Ol PO - 00 -t lOO 1^ T^ . . T ^fe - fi 5 00 tt ■r S d am rtod ri -1- f4ll-^ 6 d « 4I -' - '^« 1 ++ t- . . Of,^„ t^ d " nil fs5 -r m PO :2i CO '-' < " J "^ "'" " " 4> Ov t- IT) ir, 00 4) HiO CM~- Ol - -r ti n ri t. o w M r^O -t Tf « in m in 00 Ol K 4) ^ t 4) O PI O d d. f 4. " "i ro 1 '^.j Y m ino' d. pi dv t t^ 0' ri c ^6 C ^S— -tu^io 00 •-" m m i^ n « t -t .-f 0\ 00 •* rt 3 "UvO w « P) « PI ho OiOiO -t >> ^ < ^' CO 2 "^ °' M 4J PI O ■.- t CMn -1- c " "^ 4) « t^~? « 00 0. m une 2 4 terna Clear 640 52.0 50.8 PI n c. t- 00 d -0 fjl- - '^m'^++ pj . . pp ";i q c d • • "^ d. d m Ol d 3 00 ■ -co -t « • • « « 5> 00 i^ « ho -t •- 'o PI m -^ < « CO 2 2"°" " CD 4> _ OV -M IT) -t 01 ro 10 I- -r 00 t ^ 4)vO t 4) 'O " PI -t •- Ov -; -t d '--ll-il - - ro ' ^+ + ce » - .00 00 lA, - ■ • « _; c *? "? 4> r~ -. -tooo Ov coo 0. m ^S C 4)p, -t-O -t 3 -ijUo 1-0 ■ • r. " - - -t {r in "5 PI - PO CO ^ < " to Z? « " « " D 00 ii .o-r P» " PI M "S -> s K M 0! U MI, C oJ . . «o n 41 fo -I HI q 00 -T I-;. d d -il 4. " ^ P) PI M 0\ Oi d 00' -T in ~> in 00 go m 4> m i-« 00 00 00 T moo di pi 1 C^ ajp -TO 1- 00 c^ O* **> c 'o 4) PI - 00 -n « PI 3 iiUo PI ►-. p) J; o> r^ M .-, ^ t -.^ 1/5 -t 00 Si I- fC >~ PI OOC E K 5; CO S 4) fO -! i-iO PO 1- PI ^1 1' 1 ++ t~ m t PI Pt p« 4 d -^o vd m 00 4, C.S p^ i-i Ol PI 00 t- d o c 5— -to •* 00 Oi Oi <> m 3 c l> PI ^ C PI 00 -O 3 iiCJO PI « PI TT T PI 3 ^ - r. 4> 10 .i in -t in 10 •« m 4)00 S S f^" c s— -to ■* . m . .mm 4) q q 'T - ■.§U^-i- • - ■ • i^ -; • • • C.S m'4mo » d 3 r- -t PI Ci PI "^ ^ 13 r<5 0> Ov Ol P5 Ol 00 d c>. t HI 3 SUo • p< . „ . . „ „ ,}• -> < " .3 .a ■" .ti « 4J „- — 'v . " .3 ...... . . . .'5 . 'S J3 J= -c C ta "t: ? c c <-. 3 t, 4) u) 4> "u 4) S S 4) M - « SO ^ pounds . pipe, inches of inches of watei inches of water re room . 3 4> 0. E riheit eit Fahrenheit . Fahrenheit . degrees Fahr 3 Fahrenheit degrees Fahr er, degrees Fah Fuel ounds t. . . . nied, pounds . , pounds nsumed, pound ;nt. . per Hour our, pounds ur per square fo are foot heating 41 C Date of tests, 1900 Duration of test, hours Kind of start State of weather Heating surface . Grate surface Ratio of heating surface to Average H "■^ S M !_■ " 1-" s y gauge, base of furnace, ash pit, closed fi rt > < 1 air, degrees Fah m, degrees Fahrei ring heater, degre ing heater, dcgret ter entering boile ring ash pit, degr g gases from boile 41 -C E ocahontas coal of coal as fired, p e in coal, per ceni of dry coal consu of ash and refuse, of combustible co n dry coal, per ce Fuel 1 consumed per h i consumed per ho ;nds 1 per hour per squ; 3 ■a o o 4) :er, inche ressure b draft at draft in draft in draft in 41 Oj to 4) c ■& B W 4> E 3 Baromel Steam p Force of Force of Force of Force of Externa Fire roo Air ente Air leav Feed wa Air ente Kscapim C 'a ol Kind, P Weight Moistur Weight Weight Weight Refuse i Dry coa Dry coa! pou Dry coa! 158 . M 00 O O 1-0 M o '. o o O w r^ m M ro ■O lO 0\ M f^ O "0 o ^0 -t o >-< o. M o o ■rt- o in r< ■* n n vO t^ •* O -t o CN c* ri o O M t^ lO ro l^ roo 0^ t-t c» O fO o> C-. t^ O M " W M O o- 1~ O N M •* Tt 0\ r^ ro »0 CO CO I^ O -^t OvO CO ro 'o o ^ -r! , 1) u n! 3 rr - -M > OJ 3 CT 0) ft M > tfl > F 3 3 3 C u n [xl« g<- oj' V. fti^ fe C ^dS W V >. •o .S-i-St;; fti 3*5 2 8 2^ ^ o ft&S-o 3r3 i^a^-a^s ^ o H-« o— , <" o o evap V coa lent und lent und 1- o ^ S u, rt o d o ^^ >. Q.> ft M d M X. j: o (/I "I- w Tl o bo C "o c •d o •3 6 it: c n! o '4. 3 j^ vO ^ ft & (U t! 6 i j= ^ f^ § £ - ._ o bo ^ C d bo c c c -- rt v^ */ •_s -S -g S ■d "> 'J- ^ d g . m d S o i; : c =^. z r. S-S o ^ ii > „ -- : b^ ft c i ^ °-^^ ; " : n> ° o ,. ' .5 4) •" bo O S .s -^ tl 3 5 I 1 ft l! 3 ~° 3 . 2. bo ffi j= .S ■ o ^ " a! oi E -• p^ .S- c bo M ' 6 5. 2; j^ c H ic . •• S > '^ ic 60 .M 1- t. ^ C O 01 OJ •ii ^^ OJ OJ <1> S C " P^ ft CL, j1 . - (U (U 1) •5 > > > w < 20.1 y 17.7 y 18.6 >- 18. 5 161 162 TESTS OF A BABCOCK & WILCOX MARINE BOILER, BUILT FOR A SEA-GOIXG DREDGE FOR THE INDIAN GOVERNMENT (The tests were made at the Babcock & Wilcox Works, Renfrew, Scotland) Date, 1899 Duration of test, hours Heating surface, square feet Grate surface, square feet Kind of fuel used Kind of draft Amount of draft at base of funnel, inch Average gauge pressure, pounds per square inch . Average temperature of feed water, degrees Fahrenheit Mean temperature of gases in funnel, dgs. Fahrenheit Total coal fired, pounds Total refuse, pounds Percentage of refuse Coal fired per hour, pounds Refuse per hour pounds, Combustible per hour, pounds Coal consumed per square foot grate per hour, pounds Water evaporated per hour under actual observed con- ) dition, feed water 40 degrees Fahrenheit, pressure [■ 180 pounds, pounds ) Equivalent weight of water evaporated per hour with feed at no degrees Fahrenheit, pounds Water evaporated per pound coal per hour, actual ob- served conditions, feed water 40 degrees Fahrenheit, pressure 180 pounds, pounds Water evaporated per pound coal per hour, from and at 212 degrees Fahrenheit, pounds Water evaporated per pound of combustible per hour, actual observed conditions, pounds .... Water evaporated per pound of combustible per hour, ) actual observed conditions, from and at 212 degrees y Fahrenheit, pounds ) Water evaporated per square foot heating surface, as- suming feed at no degrees Fahrenheit, pounds Water evaporated per square foot of grate area, assum- ing feed at no degrees Fahrenheit, pounds Theoretical total heat value of fuel by Thompson's calorimeter, British thermal units .... Efficiency of boiler, per cent December 28 December 29 December 30 8 8 8 2835 2835 2835 77 77 • 77 S. Hetton Waynes Merthyr (Welsh) Black Band (Newcastle) (Scotch) Natural Natural Natural •35 ■45 -4 180 180 180 45 40 40 635 643 620 15600 15600 15600 800 1680 2496 51 10.7 16 1950 1950 1950 100 210 312 1850 1740 1638 25-32 25-32 25-32 16112 17700 15625 18013 19877 17546 8.26 9.08 8.01 10.11 II. 15 9-85 8.7 10.17 9-54 10.65 12.5 11-73 6.3 7- 6.19 234 258 227 13460 13660 12870 72.6 78.9 74 Note. — The evaporation obtained showed the boiler to be of a capacity suitable for a 1200 indicated horse- power triple-expansion engine of economical construction, using 14 to 15 pounds of steam per indicated horse- power per hour. 163 METHOD UP INSTALLING BABCOCK & WILCOX BOILERS IN THE S. S. "KVICHAK" While the vessel was still on the stocks, an opening was left in the side opposite the boiler space. The boilers were raised on crib work, and slid through the opening on to their foundations, after which the frames were erected and the plating completed. 164 COAL CONSUMPTION TESTS OF S. S. "JOHN W. GATES"* Between October lo and 15, 1900, tests were made on the lake steamer "John W. Gates," owned by the American Steamship Co., by Lieutenant-Commander J. H. Perry and Lieutenant B. C. Bryan, U. S. N. Four tests in all were made, of ten, four, eight and six hours' duration, re- spectively. During the tests indicator cards were taken from the main engines, and the usual observations of i3ressures and temperatures recorded. The coal was carefully weighed and logged on each test. Tests Nos. I and 2 were made with the vessel light, on the up trip, in Lakes Huron and Superior, respectively. Test No. i was made under the usual running speed of the vessel when light, and amounted to merely weighing coal and taking observations for ten hours out of the run. Test No. 2 was made using a steam jet in the smoke pipe to increase the draft. Tests Nos. 3 and 4 were made on the down trip, after having loaded at Two Harbors, Minn., with about 7000 tons of ore, the vessel drawing about 17 feet 10 inches of water. Test No. 3 was made at the usual running speed, and Test No. 4 with draft increased by steam jet in smoke pipe. The machinery of this ship was built under the supervision of the Chief Engineer of the American Steamship Co., Mr, Joseph F. Hayes, and the great economy obtained is largely due to his care in the design and arrangement of the plant. The ratio of the high to low-pressure cylinder area is 1 to 13.22. Joy valve gear is used on the high and intermediate-pressure cylinders, giving in the high-pressure cylinder an admission of steam almost perfect, as is shown by the indicator cards therefrom. The cylinder ports are made large, while the clearance is reduced as much as possible. A feed heater is provided, into which all the auxiliaries necessary for heating the feed water are exhausted. The dynamo when running exhausts into the third receiver of the main engine, and all precautions have been taken to make these engines economical, and with great success, as is shown by the results. The type of Babcock & Wilcox boiler adopted, known as the "Alert" type, is one that the recent tests made by Government officials show to be exceedingly economical under various conditions. It is provided with baffle plates directing the products of combustion three times across the tubes before leaving the boiler. Each of the two boilers installed is 10 feet long, ii feet 8 inches wide, and 13 feet 10 inches high, containing 3000 square feet of heating surface and suitable for 65 to 70 square feet of ordinary grate surface for hand firing. The total grate sur- face of all stokers is 108 square feet. The weight of the two boilers dry is 109, 260 pounds, and with water, 132,590 pounds. The bottom and top rows of tubes are 4 inches in diameter and all others are 2 inches in diameter. All tubes are of seamless cold-drawn steel, the 4-inch tubes being No. 6 B. W. G., and the 2-inch tubes No. 10 B. W. G. in thickness. The lengths between headers is 9 feet. The main propelling engine is of the vertical, direct-acting, inverted, jet- condensing, quadruple-expansion type. * Extracts from Journal of the American Society of Naval Engineers, vol. xii. 165 Number of cylinders 4 ^ High-pressure 16 3^ Diameter of cylinders, j First intermediate-pressure . . 25 in inches | Second intermediate-pressure . . 38 3^2 (^ Low-pressure 60 Stroke, inches 40 Diameter of piston rods, inches 4^4 Order of cylinders from forward: (i) high-pressure, (2) first intermediate- pressure, (3) second intermediate-pressure, (4) low-pressure. Sequence of cranks: high- pressure, low-pressure, first intermediate, second intermediate. The high-pressure and first intermediate-pressure are at 180 degrees, as are the second intermediate-pressure and low-pressure, the former being at 90 degrees with the latter. There is one four-bladed propeller, 14 feet in diameter with 15 feet 6 inches pitch. Two mechanical stokers of the Crowe pattern were fitted to each boiler. This stoker consists, essentially, of a set of bars carried from front to back of the furnace, over a number of fair leaders, by two chains, one on each side of the furnace. At the back of the furnace the chains and bars pass over a drum and thence back over fair leaders to the front of the furnace again. During the entire trip the stokers worked satisfactorily. During most of the time little or no smoke was emitted from the pipe except while the fires were being worked from the back, or when an additional amount of coal worked in under the plate in the front of the furnace. The air pump worked regularly and quietly, but for some reason, probably due to the large clearance required in the cylinders of this type of pump, the vacuum carried was not much in excess of 233^ inches. Lead did not melt during anj^ of the tests when suspended in the up-takes just over the top row of 4-inch tubes or practically where the gases leave the boiler proper. Lead suspended in the boiler where the gases leave the last row of 2-inch tubes melted on the test of October 15, but only softened on the tests of October 10 and 13. A i)roximate analysis of the coal used, gave results as follows : Per cent. Fixed carbon 57-oo Volatile matter 37-oo Moisture 2.00 Ash 4.00 100.00 Heating value of coal by calorimeter . . . . 13,180 B. T. U. The following table gives the data and results of the tests: 166 COAL CONSUMPTION OF S. S. "JOHN W. GATES" Number of test I 2 3 4 Date, 1900 Oct. 10 Oct. II Oct. 13 Oct. 15 Duration of test, hours .... 10 4 8 6 Steam ( At boiler 244 244 248 250 oieain i ^^j. receiver . pressure, 4 ^^^ ^^^^-^^^ _ pounds ^ ^^ ^^^^.^^^ _ 107.8 324 7-5 II3-9 34-1 7-9 107.7 32.9 6.5 108.7 34-0 9.0 Vacuum, inches . 24 23-3 233 23.0 Temner f Engine room . at^?e Injection water 83-5 61.3 82.7 53-6 80.0 50.0 76.2 61.3 , ' < Hot well feed water entering ^^g^^^^ ^ heater l^Feed water leaving heater . II3-5 II3-9 II7-3 115-3 186.0 179-7 187.0 186.5 Links in from i High-pressure 30 •75 3-25 •75 f 11 th J istmtermediate-pressure 3-5 1.5 to 2.25 375 1. 00 luumrow, -j 2nd intermediate-pressure 3-5 1.75 to 2.25 375 1.50 mcnes ( Low-pressure . 4-5 1-75 375 2.25 r High-pressure cylinder . 1st intermediate-pressure 340.1 425.6 330.2 437-8 Indicated 1 cylinder 388.5 516.6 354-2 490.7 horse-power ^ 2nd intermediate-pressure .«/ 340.1 417.9 346.5 390.0 Low-pressure cylinder . I Total 362.0 458.2 312.7 465-9 1430.7 1818.3 1343-6 1784.4 Revolutions per minute, main engine 82.77 89.8 77-84 85-36 ' Total coal, moist, pounds . Moisture in coal, per cent. Coal ■{ Coal per hour, dry, pounds 22270 14535 17099 20655 4.1 4-1 4.1 4.1 21357 3488.7 2049.8 3301.4 Dry coal per hour per square foot l^ of grate surface, pounds . 19.77 32.26 19.98 30.58 Coal per indicated horse- j Coal as fired 1-56 1.998* 1-59 1-93* power main engine, pounds ( Dry coal . 1.50 1.92 1-53 1.85 Draft in up-take, inches of water . •30 Jet in funnel fet in funnel .58 •33 .60 Temperature of waste gases j Lead did I not melt Lead did not melt Lead did not melt Lead did not melt Time dynamo engine was in operation . 3 hours 2 hours 55 minutes Not running Double strokes \ ^'' P""^P' hig^-P'"^^^^^^ 22 237 20.1 19.0 per minute j Air pump, low-pressure ^ [ h eed pump . 19 18 22 24 18.8 18.7 16.2 23.8 * The increase in coal consumption per indicated horse-power is caused by the waste of steam due to increas- ing the draft by means of a steam jet in the funnel. This jet was supplied by a i^^-inch pipe and nearly doubled the draft. Auxiliaries in Operation: Air pump, feed pump, stoker engine and dynamo engine part of time, as noted above. 167 : ^ : u o z 168 REPORT OF TEST OF A BABCOCK & WILCOX BOILER FOR U. S. BATTLESHIPS "WYOMING" AND "ARKANSAS" with notes by Lieutenant Commander H. C. Dinger, U. S. N.* A Babcock & Wilcox boiler, representing the type proposed for installa- tion on the battleships "Wyoming" and " Arkansas," was tested by a Board of Naval Officers consisting of Commander C. W. Dyson and Lieutenant Commanders J. K. Robison and H. C. Dinger, U. S. N., on June 13 to 20, 1910. The contracts for the above vessels call for economy tests of one boiler of the type proposed before installation on the vessel. The test boiler is similar in all respects to those which will be installed on the vessels, except that it is half the width. The actual boilers for the vessels will have 119 square feet of grate and 5,353 square feet heating surface, instead of 57.89 square feet of grate and 2,571.39 square feet of heating surface in the test boiler. The contract required four tests of twenty-four hours each at successive rates of combustion of approximately fifteen, twenty-five, thirty-five, and not less than forty pounds of coal per square foot of grate surface per hour, beginning with the lowest and ending with the highest rate of combustion. Conditio7is of Tests. — The tests were required to be conducted continu- ously, except that a maximum time of two hours will be allowed for cleaning fires after each twenty-four-hour test before beginning the next twenty-four- hour test. The only cleaning of boiler tubes allowed was by the use of steam or air lances in the same manner as is customary in actual service ; the fuel to be clean bituminous coal, and allowed to be hand-picked; each test to be made at maximum pressure of 210 pounds above the atmosphere, and the average air pressure in the fireroom at the highest rate of combustion not to exceed two inches of water. The equivalent evaporation from and at 212 degrees F. at the highest rate of combustion of not less than forty pounds per square foot of grate surface per hour was required to be not less than eleven pounds of water into dry steam per pound of combustible. These contract requirements were intended to represent actual service conditions as nearly as possible. The tests were arranged so that the effect due to accumulation of soot after several days' steaming would be taken into account. Thus, the results of the test at 40 pounds per square foot of grate represent the performance of the boiler when called upon for full power after several days' steaming. ♦Reprinted from Journal of American Society of Naval Engineers, for November, 1910 (Vol. xxii). 169 -BLOWER ENG. / / TEST HOUSE GAS ANALYSIS - BOOTH ARRANGEMENT OF TEST BOILER AND TEST HOUSE. BABCOCK &. WILCOX CO; 170 The following extracts are from the report of the Board, with some additional notes. The data given are from the Board's report. General Arrangement. — ^Thc apparatus was arranged as follows: The boiler was erected in a sheet-iron structvirc, the general arrangement of which is shown in the cut on p. 170. The arrangements for supplying forced draft are also shown. The blower discharged at floor line at the back of the boiler, against a vertical baffle wall, which deflected the air upward. The main steam pipe connected to the steam main for power house, and by a bleeder valve to an atmospheric discharge, terminating in a three-branch muffler. Both discharges were controlled by stop valves with stems extending to fircroom floor. Feed Heater. — A Rcilly feed heater was used, with a branch from the main steam pipe for supplying the necessary steam. The pressure in feed-heater shell was regulated by a valve in the steam-supply pipe. This heater was tested for tightness before and after each test. Steam Jet. — A pipe led from the main steam pipe to a jet in the smoke pipe, with a valve for regulating the amount of opening. Smoke Pipe. — -The smoke pipe was of sheet-steel, having 19.63 square feet cross-sectional area, 100 feet in height above the grates. The location of smoke pipe with regard to up-takes is shown on the diagram. Calibrated thermometers were placed in the feed pipe as close to the boiler- feed stop valves as possible. Two nitrogen-filled thermometers were located in the up-takes for obtaining the temperature of the escaping gases. A thermometer for obtaining temperature of the outside air, and an aneroid barometer for in- dicating atmospheric pressure were hung outside of the testing room. The draft pressures were taken through tuloes inserted in the lowest dusting door of the first gas passage and in the highest dusting door of the last passage, the air pressure in compartment being measured by an air gauge hung on the bulkhead of the compartment. Gas Anaylsis. — An Orsatt apparatus for making analyses of the furnace gases was located in a small compartment adjacent to the test room. The gas samples were taken from the up-take by means of a J^-inch pipe leading to the gas-analysis apparatus. Samples of gas for analysis were taken at frequent intervals. Method of Weighing Coal and Ashes. — A platform scale for weighing was situated in the air lock. The coal was weighed in barrows, the weight of empty barrows being carefully checked at intervals. Each barrow was carefully balanced with a load of 200 pounds of coal. The weighing was all performed in the air lock. No inconvenience by reason of the boiler room being under pressure was experienced. At the end of each hour the floor was swept up and estimate of coal on floor made. Method of Weighing and Pumping Water. — The arrangements for weighing water consisted of a rectangular feed tank on top of which were located two weighing tanks mounted on platform scales. The scales were tested before and during tests, and weights of empty tanks were checked at intervals. The water was led from the city main to each weighing tank, where, after being weighed, the tank was dumped into the feed tank. The feed tank was calibrated 171 172 and fitted with a gauge glass so that the water eould be ehccked at any time. The boiler-feed pumps had a suction and an overflow pipe to the feed tank, and discharged through feed-water heater to the main feed valve on boiler. A steam gauge and water gauge, indicating steam pressure and water level in boiler, were located at the pump, thus assisting in pump regulation and in maintaining a constant feed supply. At the end of each hour the actual amount of water was checked up. Quality of Steam. — For observing the quality of the steam generated a Bar- rus throttling calorimeter was fitted on a branch from the main steam pipe at a point about i8 inches from the steam drum. The collecting nozzle was of standard pattern. The calorimeter was calibrated before the tests by taking readings with the pressure both rising and falling, with no steam leaving the boiler except through the calorimeter. From these standard readings the amount of moisture was calculated by the formula Q = — — J X 100, in which Q = per cent, of moisture, T = calibration reading of the lower ther- mometer, / = test reading of the lower thermometer, L = latent heat of the steam at the boiler pressure. Moisture in Coal. — Samples of coal were taken for each test, preserved in airtight jars, and from these the moisture in the coal was determined by laboratory test. Co7idition of Fires and Ash Pans at Beginning and End of Tests. — The depth of fires was judged by a member of the Board at the start and at the end of each test, the fires having been brought to similar conditions at the beginning and the end of each test. Ash pans were clean at the beginning of each test, and were cleaned at the end of the test. Water was used very sparingly in the ash pan, but was always used at the times that fires were cleaned. Fires were cleaned on each of the twenty- four hour tests shortly before the end of test in order to enable them to be brought as nearly as possible to the same condition as at the beginning. The Tests. — Six test runs were made, the first four being those required by the contracts for the "Wyoming" and "Arkansas," at rates of combustion of 15. 25, 35, and 40 pounds of coal, respectively, per square foot of grate, each test being for twenty-four hours. The fifth test was a test for the maximum capacity of the boiler, and con- tinued for three hours. The sixth test was made at the rate of about 45 pounds per square foot of grate per hour, to determine the effect of lowering the back end of grate six inches below the position in the previous tests. Coal. — The coal was hand-picked Pocahontas of excellent quality. It burned freely and clinkered very little. The coal used on all the tests was from the same lot. Firemen employed. — The firemen emjDlojxd were ordinary marine firemen 173 picked up on the Hobokcn docks for the time being, and were given no special training for the tests or for this particular type of boiler. Several firemen were discharged for drunkenness and others taken on during the tests. One water tender, two firemen, and two coal passers were on duty in each shift. The operation of the boilers and of the firing was supervised by the Company's engineers, who stood watches in three shifts of eight hours each. The excellent evaporative results obtained indicate the high efficiency pos- sible with the ordinary run of firemen, if properly supervised and directed. This FERRYBOAT "SAN PEDRO." Owners: Atchison, Topeka & Santa Ffi Railway Company. Babcock & Wilcox Boilers. Horse-power 2500 I.NDICATED supervision provided for careful and regular firing, keeping fires level and not over eight inches thick, with proper use of the slice bar and leveling hoc. Special attention was paid to making all the boiler casings airtight. Methods oj Starting and Stopping Tests. — In the first test the alternate method of starting and stopping the test was employed. In the second and all succeeding tests the flying start was employed, it being much more satisfactory under the conditions required by the contract than either the standard or the alternate methods. Gas analyses were taken by one of the Company's engineers, closely observed by members of the Board. All other data were taken simultaneously by repre- sentatives of the Company and by one member of the Board and the assistants to the Board. Test No. I. — At 15 ])Dunds per square foot of grate ])er liour. Begun at 6:08 p.m., June 13; finished at 6:08 p.m., June 14, 1910. 174 Weather during the test, warm and clear. The blower was not run, the compartment was open, and the steam jet closed. The evaporation from and at 212 degrees F. per pound combustible was 12.15. Test No. 2. — At 25 pounds per square foot of grate per hour. Begun at 8:30 p.m., June 14; finished at 8:30 p.m., June 15, 1910. The steam jet was partly open. The forced-draft blower was used to ven- tilate the fireroom, but the compartment was not closed. Weather during the test was warm and clear, slightly cloudy at the end of the test. The evaporation from and at 212 degrees F. per pound of combustible was 12.07. Test No. J. — At 35 pounds per square foot of grate per hour. Test begun at 10:25 p.m., June 15; finished at 10:25 P-^-, June 16, 1910. The steam jet was partly open. The forced-draft blower was in operation and the compartment closed. Weather during test, cloudy and rainy. Rate of evaporation from and at 212 degrees F. per pound of combustible was 11.77. Test No. 4. — At 40 pounds per square foot of grate per hour. Test begun at 11:30 p.m., June 16; finished at 11:30 p.m., June 17, 1910. The steam jet was partly open. The forced-draft blower was in operation and the compartment closed. Weather during the test, rainy during the first twelve hours, clear the last twelve hours. The evaporation from and at 212 degrees F. per pound of combustible was 11.89. Test No. 5. — At maximum capacity. This test was conducted on June 18, 1910. The fires were lighted with the boiler in following condition: Temperature of water in boiler, 102 degrees; water level in glass, 1^4 inches; furnaces primed. Lighted fires at 9:04 a.m. Steam formed at 9:12 a.m. Steam pressure 50 pounds, 9 h., 16 m., 30 s., a.m. Steam pressure 100 pounds, 9h., i8m.,A.M. Steam pressure 150 pounds, 9 h., 18 m., 55 s., a.m. Steam pressure 200 pounds, 9 h., 19 m., 45 s., a.m. Steam at 200 pounds in 15 m. 45 s. The test began at 9:38 a.m., and ended at 12:38 p.m. The steam jet was wide open. The forced-draft blower was in operation, and the compartment was closed. At the end of this test the fires were hauled and boiler carefully examined. There were no signs of any leaks, and no distortion of any kind, either in tubes baffles or casing, was noticed. The weather during the test was clear. The evaporation from and at 212 degrees F. per pound of combustible was IO-33- 175 ■ty.''\ 'ft 176 I Test No. 6. — At rate of 45 pounds per square foot of grate per hour, with the back end of grate lowered six inches below the level at which it was carried during the previous tests. Test begun at 10:00 a.m., June 20; finished at 4:00 p.m., the same day. The weather during the test was clear. The evaporation from and at 212 degrees F. per pound of combustible was 11.30. S. S. "KIANG WHA" The China Merchant Steam Navigation Company. Babcock & Wilcox Boilers, 2750 Indicated Horse-power The curve of rate of evaporation appears to show that there is a very small falling off in efficiency until a consumption of about 45 pounds of coal per square foot of grate per hour is reached, and that the boiler is almost as efficient at high rates of combustion as at moderate rates under natural draft. This is a highly gratifying result and indicates that the system of baffling is very efficient. The difference in evaporative results, with the original grate and with the back of grate lowered, is insufficient for determining whether there is any actual advantage or disadvantage due to the lowering of the grate, when coal alone is used for fuel. The Board reports that the sample boiler tested, representing the type of boiler to be supplied for use on board the U. S. S. "Arkansas" and the U. S. S. "Wyoming," has fully met all requirements of the contract as to evaporative efficiency, and recommends the approval of this type of boiler for general use in the naval service. 177 178 REMARKS The firemen, while completely unskilled, so far as test boiler firing was con- cerned, soon became very much interested in the results of the gas analyses, and realized the value of so firing as to maintain as high a percentage of CO 2 as possible. This interest manifested itself very early in the tests, in the de- creased density of the smoke escaping from the stack. Particular attention is called to the excellent results obtained with this boiler under the maximum rate of combustion obtained, which slightly exceeded seventy (70) pounds of coal per square foot of grate per hour. The boiler under this condition steamed very freely, with no appreciable increase in the wetness of the steam, while the falling ofif in efficiency under all test conditions, from the lowest rate of combustion to the highest, was small and very regular. After the completion of the tests the boiler was opened, cleaned, and thor- oughly inspected for deterioration. Not a tube showed any signs of distortion, all tubes and headers were perfectly free from blistering, and all baffies were still properly placed. This result would seem to indicate that when a boiler of this type is clean, free from scale, and built of proper material it is perfectly safe under all regular rates of combustion, up to the highest rate to which it was subjected in these tests. This finding, necessarily, supposes intelligent super- vision and proper regulation of feed water during such rates of combustion. DESCRIPTION AND DIMENSIONS OP BOILER AND APPURTENANCES Diameter of drum, inches 0-42 Length of drum, feet and inches 10-03^^4 Tubes, number, 560; outside diameter, inches 0-02 length, feet and inches 8-02 thickness No. 10 B. W. G. number, 16; outside diameter, inches 0-04 length, feet and inches. 8-02 thickness No. 6 B. W. G. number, 16; outside diameter, inches 0-04 length, feet and inches 6-04 thickness No. 6 B. W. G. Furnace, kind of Single, full width of boiler length, average, feet and inches 7-05 width, feet and inches 8-03 J<^ height, average, feet and inches 3-01 Grate surface, length, feet 7-00 width, feet 8-0334 area, square feet 57-89 Heating surface, area, square feet *2,57i.39 ratio to grate 44.4 : i Grate bars, kind (double) U. S. Navy Standard Bar width of air spaces, inch o-oo3^ ratio of grate to air space i : 0.427 Smoke pipe, area, square feet 19-63 height, feet 100.00 ratio to grate i : 2.94 Water space, cubic inches 301,561.0 Steam space, cubic inches 102,889.0 179 o CQ (~ X y. o o o PC i^ CI "? On CO 00 00 ro 00 -+ ^1 -1^' Ah g o CO c ro 4 OO ro 00 CJ \d Q0_ ci CJ ci pq " vq -1- CO 0) o -1- ro ON On CO ro 00 ID l-H ro 00 OO' tu C Ah g q 1^ VD 1 rt- q 1 -:!- ro -t- »— ( ID ?^ cl CI ci ro PQ ID ro o ro ID ro Ct 00 ro CO ID N q 1^ q •^ -1- ro CJ ro ci H- 1 O GO 06 ID OS ro 1^ pq CD 01 ro OS lO CM ro CO d ON ro 00 ro 00 ID *-i CO u -i-j Ah CJ -i- 1^ t^ q CI ro ON q ON q 00 On 1— 1 On ro -i- "? ci 1^ pq CO r-i d ID ro ro CO 1 CO i' ? tu o e c o o c o &, ^ u .2 ^ a o Is OS '-J ^ K ^3 C o 'o o >. O VC nJ o o OJ o 13 o o o 1-, 'o e O CD 3 r:) in xn O c u o •2, o 'a o a o l- ci o ^ cd O c £ o o "a S o o .s o -M o (U C 3 O g 3 22 s s §•§ H «^ r-) m n e "0 'd u, a. U c CJ !-, '0 c _o "0 V. (U V-t O- nj n 'd c a \-, 0^ "0 J2 "0 >, c _aj "u JE W 71 ■i Z, o o < o 311S3U1 0VOU1IVU -savo XNVJ. 1 1 86 TEST OF A BABCOCK & WILCOX BOILER WITH LIQUID FUEL Reprinted from the Journal of American Society of Naval Engineers, May, 191 1 (Vol. xxiii). From the Board's Report This test was conduetcd by a Board composed of Captain C. A. Carr, U. S. N, and Lieutenant-Commanders J. K. Robison and John HalHgan, Jr., U. S. N. The Board assembled at the works of The Babcoek & Wilcox Company, Bayonne, N. J., about 10 a.m., November 28, 1910. The Board examined the test boiler and its connections for water and steam tightness, the arrangements for measuring water and oil and the apparatus for taking data. All of these were found satisfactory, and the tests were proceeded with at once. In all these tests oil was used as a fuel. Civilian assistants from the office of the Inspector of Machinery, Bayonne, N. J., were detailed for the purpose of taking data. Another set of observers was furnished by The Babcoek & Wilcox Company who took data independently. The data taken by the two sets of observers were compared, so that any errors in reading were corrected at once. The boiler tested was of the t^^pe installed on the U. S. S. "Wyoming" and U. S. S. "Arkansas," and is the same which was tested June 13 to June 20, 1910, during which tests coal was used as a fuel. No changes have been made in the design of the boiler except for the removal of the grate, the bricking over of the ash pans and the sides up to the side boxes, and the necessary changes in the furnace front incident to the installation of the oil-burning apparatus. The following particulars apply to the installation for burning oil: Type of boiler Babcoek & Wileox Total heating surfaee, square feet 2,571 Volume of furnaee, cubie feet 217 Area of eross-section smokepipe, square feet 19-63 Height of smokepipe above furnace, feet 100 Fuel used Crude oil from Gulf Refining Company Kind of draft Closed fireroom and jet in smokepipe Number of burners 11 Type of burner Peabody Mechanical Atomizer For convenience in referring to burners in use during the different tests, they are numbered from left to right in each row consecutively, the left-hand burner in the upper row being No. i. General Arrangement. — The arrangement of the apparatus used in mak- ing these tests is shown on the attached sketch. The arrangement for supplying forced draft is also shown on this sheet. The blower for supplying forced draft was driven by a vertical steam engine through a belt. The air duct discharged at the floor line of the fireroom at the back of the boiler against a vertical baffle wall that deflected the air upward. The main steam pipe con- nected to the main steam pipe of the power house and by a bleeder to the atmos- 1 88 pheric discharge, terminating in a three-branch muffler. The discharge to the power-house main and to the bleeder were controlled by stop valves with extension stems to the fireroom floor. Feed Heater. — A Reilly feed heater was used for heating the feed. A branch pipe from the main steam pipe led to the feed-water heater for supplying the necessary steam. The pressure of steam in the feed-water heater shell was regu- lated by a valve in the steam pipe to the heater. This feed heater was in use during all the tests except for about 42 minutes in test No. 2, when the auxiliary feed pipe was used, owing to a temporary derangement of the main feed pump. The auxiliary feed pump took weighed water from the main feed the same as the regular pump. The feed heater was tested before and after the tests under a water pressure of 220 pounds and was found tight. Steam Jet. — A pipe led from the main steam pipe to a jet in the base of the smokepipe, the amount of opening being regulated by a valve. This jet was used for increasing the draft, as noted in the log of the tests. Smokepipe. — The smokepipe was of sheet steel, 19.63 square feet area of cross-section, and 100 feet in height above the furnace. There was a damper in the smokepipe, which was wide open during all the tests. The discharges from the surface and bottom blow valves led into a pipe which led outside of the building and the end of which was open. A slight leak was found at the end of this pipe soon after starting test No. i , which could not be stopped by setting down on the blow valves, and the end of the pipe was therefore plugged, insuring tightness. It was examined during every succeeding test and no further leaks occurred. Thermometers were placed in the main feed pipe as near the boiler-feed stop valve as possible, and in the oil-pressure pipe near the burners, and a nitrogen filled thermometer in the uptake for obtaining the temperature of the escaping gases. Thermometers were also hung in the fireroom and outside the testing room for observing the temperatures of the air. The draft pressure was taken through a tube in the highest dusting door of the last gas passage. In tests Nos. 4, 5, and 6, it was also taken through a tube in the lowest dusting door of the first gas passage. The air pressure in the fire- room was also measured by an air-pressure gauge hung on the bulkhead of the testing room. Gas Analysis. — An Orsat apparatus for making analyses of uptake gases was located in a small booth adjacent to the test room. Gas samples were taken from the uptake by means of a i^-inch pipe leading to the gas-analysis apparatus. Samples of gas were taken at frequent intervals by the chemist of The Babcoek & Wilcox Company. The results of the analyses were immediately reported to the company's engineer for his information. Method of Weighing Oil. — ^The arrangement of the oil- feeding apparatus is shown on the diagram. Two barrels for receiving and weighing oil were mounted on platform scales. These scales were examined before and after the tests for correctness, and were checked during the tests by weighing empty barrels. Oil was run into these barrels for weighing direct from the tank car in which it was received at the works. The flow of oil was assisted by a small pump, the location of which is shown on the sketch. After being weighed the oil was run into one 189 r 190 of the two receiving barrels shown. These two barrels were connected at the bottom by a 4-inch pipe, the oil-feed suction being led into the second barrel. This second barrel also received the overflow oil from the relief valves of the oil- pressure pump. From the top of this barrel the height of the oil was measured by a gauge, to determine the quantity of oil burned. From the pressure pump the oil passed through strainers to the oil heater. A pressure gauge and a ther- mometer were fitted in this room on the oil-supply pipe for convenience in regu- lating the temperature and pressure of the oil. The quantity of oil burned could be determined at any instant by measuring the level of oil in the barrel. At half-hour intervals the quantity of oil was checked up. Method of Weighing and Pumping Water. — The arrangements for weighing feed water consisted of a rectangular feed tank on top of which were located two weighing tanks mounted on platform scales. These scales were tested before and after the tests and the weights of empty tanks also served as a check. The water was run from the city main into the weighing tanks and after being weighed was run into the feed tank. The feed tank was fitted with a gauge glass on which the height of water at the start was marked. By regulating the flow of water from the weighing tanks the quantity of water used during any time could be determined. This feed tank had suctions to main and auxiliary feed pumps and also received the overflow from the relief valves of these pumps. The main feed pump discharged through the feed-water heater to the main feed valve on the boiler. All feed piping was where it could be seen, and no leaks took place during any of the tests. A steam gauge and a water gauge indicating steam pres- sure and water level in the boiler were located at the feed pump for assisting in pump regulation and in the maintenance of a constant feed supply. At the end of each half hour the actual amount of water fed to the boiler was checked up. Quality of Steam. — For observing the quality of the steam generated, a Barrus throttling calorimeter was fitted on a branch from the main steam pipe at a point 18 inches from the steam drum. The collecting nozzle was of standard pattern. The calorimeter was calibrated after the tests by taking readings with the pressure both rising and falling with no steam leaving the boiler except through the calorimeter. The calorimeter thermometers and feed-water thermometer were compared with a standard thermometer after the tests, and readings were corrected as necessary. From these standard readings the amount of moisture in the steam was determined from the formula : Q =~^ J X 100; in which Q = percentage of moisture; T = calibration reading of the lower thermometer; / = test reading of lower thermometer; L = latent heat of steam at boiler pressure. Quality of Oil Used. — The oil used was Texas crude furnished by the Gulf Refining Company, Samples of oil were taken direct from the cars, and the characteristics of the oil were determined by a laboratory test made by the chemist at the Navy Yard, Washington, D. C. Oil from car No. i was used in test Nos. I, 2, 3, and 4. Oil from car No. 2 was used in tests Nos. 5 and 6. The analysis of the oil was as follows: 191 192 Car No. i Car No. 2 Character of oil British thermal units per pound . Percentage of moisture in oil " " silt in oil . Specific gravity at 60 degrees F. . Flash point, degrees F Burning point, degrees F. . . . Heavy and viscid 19,291 trace under i .9322 295 295 Heavy and viscid 19,086 trace under i .9322 295 295 The method of conducting tests was as follows: The steam was brought to the desired pressure and the boiler was kept in use long enough to heat all parts thoroughly and to bring all conditions approxi- mately to those under which it was desired to run the test. All observers were then called together and their watches were set to agree with the watch, used by the Board. A time was set for starting the test, and the observers were sent to their stations, and at the time set the level of water in the boiler, in the feed tank, and of oil in the feed barrel was noted. Data were observed at fifteen-minute inter- vals. A few minutes before the time set for ending the test all observers were notified when to take the final observation. The character of the smoke was observed by a member of the Board and is marked on a scale of 5, in which 5 denotes dense black and i a slight haze. Impeller boxes of burners not in use during any of the tests were blanked off by asbestos board. The boiler casing was kept as nearly tight as possible. It was necessary to replace one burner during the tests, and this was done in less than a minute. A small piece of waste was found in a groove in the washer of the defective burner. Test No. I at 13.69 pounds of oil per hour per cubic foot of furnace volume. Capacity test. — Test begun at 11 a.m. and finished at i p.m., November 28, 1910. Weather, overcast. Steam jet in use during test. All burners in use. Rate of evaporation from and at 212 degrees F. per pound of oil: 13.70 pounds. Test No. 2 at 7.85 pounds of oil per hour per cubic foot of furnace volume. — Test begun at 2 :o5 p.m. and finished at 5 :o5 p.m., November 28, 1910. Weather, overcast. Burners 2, 4, 5, 7, 8, 9, 10, and 11 in use. Rate of evaporation from and at 212 degrees F. per pound of oil: 14.37 pounds. Test No. J at 5.54 pounds of oil per hour per cubic foot of furnace volume. — Test begun at 9:40 A.M. and finished at 12:40 p.m., November 29, 1910. Weather, overcast and raining. Burners i, 6, 7, and 10 in use. Rate of evaporation from and at 212 degrees F. per pound of oil: 15.72 pounds. Test No. 4 at 3.07 pounds of oil per hour per cubic foot of furnace volume. — Test begun at i : 25 p.m. and finished at 5 : 25 p.m., November 29, 1910. Weather, overcast and raining. Burners i, 3 and 6 in use. Rate of evaporation from and at 212 degrees F. per pound of oil: 15.86 pounds. The above tests were concluded on November 29, 1910, and the Board dissolved. Upon working up the data of the above tests roughly it was found that test No. 2 did not give the efficiency equal to that which would have been expected from points in a curve obtained from results of the other three tests. On this account two additional tests were made by the senior member of the 193 194 Board, the civilian assistants of the Inspector of Machinery being present to take data. The results of these two tests are included in the report of the Board. Test No. 5 at 8.86 pounds of oil ])er hour i)cr cubic foot of furnace volume. — • Test begun at 10:40 A..M.and finished at i :40 p.m., November 30, 1910. Weather, clear. Burners i, 2, 3, 4, 5, 6, 8 and 10 in use. vSteam jet in use at intervals. Rate of evaporation from and at 212 degrees F. per pound of oil: 14.12 pounds. Test No. 6 at 8.97 pounds of oil per hour per cubic foot of furnace volume. — Test begun at 10 a.m. and finished at i p.m., December 3, 1910. Weather, clear. Burners i, 2, 3, 4, 5, 6, 8 and 10 in use. Steam jet slightly open during run. Rate of evaporation from and at 212 degrees F. per pound of oil: 15.44 pounds. All conditions of the above tests were regulated by men in the employ of The Babeock & Wilcox Company who had been employed on this boiler for some time, making preliminary tests, and they were expert in handling this system of burning oil. While the conditions existing were regulated by skilled men, the supervision of the Board was rigid, and the results obtained can be relied upon. The Board has no knowledge of authenticated tests of fuel-oil burning in which a boiler has been forced to the degree shown by Test No. i , or in which an efficiency as high as that shown by Tests Nos. 3 and 4 has been attained. The results of the tests are, therefore, considered to be particularly impressive as indicating a material advance in the art of fuel-oil burning with mechanical atomizing burners. The variations in efficiency shown by Tests Nos. 5 and 6 indicate the careful adjustment of firing conditions that is necessary in order to obtain the highest efficiency when burning fuel oil. The tests bring out the desirability of making gas analysis at frequent inter- vals when burning oil; also of watching the temperatures of the up-take closely. From the observation of the Board during these tests the character of the smoke was also an excellent guide to the results which were being obtained at any time. Changes in conditions were noted by the character of the smoke before they were apparent from the gas analysis. In Tests 3, 4 and 6 the character of the smoke was kept practically constant. It appears that the best results were obtained with the character of the smoke between i and ij/^ on the scale used, and the corresponding percentage of CO 2 in up-take gases was about 12 per cent. The Board was particularly impressed with the excellent results obtained with this boiler under the maximum rate of combustion, Test No. i, which gives a combustion of 13.69 pounds of oil per cubic foot of furnace volume. This is the equivalent of about 75.34 pounds of coal per square foot of grate area in the same boiler when burning coal. The boiler in this test steamed freely with a very slight increase in the wetness of steam, and the falling off of efficiency was small for a rate of combustion much above the maximum ordinarily used on boilers of the Navy under forced-draft conditions. After all the tests were completed the boiler was opened, cleaned and thor- oughly inspected for deterioration. No tubes showed any signs of distortion, and all tubes and headers were free of blisters. All baffles were in good con- dition and properly placed. 195 196 TABLE XXIII OIL TESTS OF BABCOCK & WILCOX MARINE BOILER Number of test Date of test. . Duration of test, hours Kind of oil Oil burner used .... State of weather . . . Number of burners in use Average Pressures Steam pressure by gauge, lbs Oil pressure by gauge, lbs . Draft pressure in fire- room, inches of water Draft pressure in furnace. Pass. I, inches of water Draft pressure near up- take, inches of water Average Temperatures Outside air, dgs. F. . . Fireroom, dgs. F. . . . Steam (at gauge pressure, tables), dgs. F. . . . Oil, dgs. F Feed water entering heat- er, dgs. F Feed water entering boiler dgs. F Chimney gases, dgs. F. . Oil Weight of oil used during trial, lbs Steam Quality Percentage of moisture . Smoke, scale of 5 ... I Nov. 28, '10 Pea Overcast II 209.9 191. 1 2.60 4-83 45-5 71. 1 391-5 175-3 47 168.6 771 5,943 99.189 .811 2 Nov. 28. '10 body Overcast 8 210.4 188.8 1.69 45 75-2 391-7 183.4 47 160.9 666 5,11- 99.290 .710 1-5 3 Nov. 29, '10 3 Texas mech Rain 4 210.7 175-6 1.64 43 70 391.8 184.0 47 201.0 533 3,605 99-837 .163 1-3 4 Nov. 29, '10 4 crude anical Rain 3 212 131-3 •33 •65 .72 46 79 392-3 210.1 47 211. 2 447 2,665 99.891 .log 1-5 5 Nov. 30, '10 3 atom Clear 214.8 153-2 1.97 1-35 2.58 43 79 393-4 199.0 46 185.6 702 5,767 99.782 .218 2-3 6 Dec. 3, '10 3 izers Clear 214.8 171.8 1.64 1.65 2.79 76 393-4 195-7 46 182.8 630 5,840 99-835 .165 I-I5 197 TT^ip 198 OIL TESTS OF BABCOCK & WILCOX MARINE BOILER— Continued. Number of test .... Water Total weight of water fed to boilers corrected for inequality of water level and steam pressure at beginning and end of test, lbs Equivalent weight of water evaporated into dry steam, lbs. . . . Factor of evaporation Equivalent weight of water evaporated into dry steam from and at 212° F., lbs Oil Fuel per Hour Oil per hour, lbs. . . . Oil per hr. per cubic ft. furnace volume, lbs. . Oil per hr. per square ft. heating surface, lbs. . Oil per hr. per Ijurner, lbs . Equivalent to coal per sq. ft. of G. S., lbs. . . . Water per Hour Feed water per hour, lbs. Water per hour, corrected for quality of steam, lbs. Equivalent evaporation from and at 212° F. per hour, lbs Equiv. evaporation from and at 212° F. persq. ft. of heating surface, lbs. Equiv. evaporation from and at 212° F. per cu. ft. of furnace ^''ol., lbs. Economic Results Water evaporated per lb. oil, lbs Equiv. evaporation from and at 212° F. per lb. oil, Us Chiitiuey Gas Analysis Carbon dioxide (CO 2) p. c. Oxygen (O), per cent. Carbon monoxide (CO), per cent Nitrogen (N), percent. . Efficiency Efficiency of boiler . . 74,898 74.291 1.096 81,423 2,972 13-69 1-156 270.2 75-34 449 146 712 15-83 187.60 12.60 13.70 9-85 6.46 .01 83.68 69.29 67,036 66,561 1. 1 04 •3,483 1,704 7-85 .663 213 37-45 22,345 22,187 24,494 9-53 112.87 13. II 14-37 9.26 7.68 .00 83.06 72.68 53,464 40,096 53,376 40,185 1.062 1-05; 1,202 5-54 •467 300.5 28.34 666 3-07 ■259 222 16.13 17,821 10,024 17,792 [10,046 18,895 7-35 87.06 14-83 15-72 11-57 4-50 .04 83.89 79-50 10,569 4.11 48.70 15-04 15.86 11.86 4.08 .04 84.02 75,714 83,573 75,549 83,435 1.078 1. 08 1 56,685 42,276 81,449 80.21 1,922 8.86 -747 240.3 43-96 90,193 1,947 8.97 -757 423-4 46.14 25,238 27,858 25,183 27,812 27,149 10.56 125.10 13-13 14.12 10.71 5-18 .02 84.09 71.41 30,064 11.69 138.53 14-31 15-44 10.94 4-73 .00 84-37 78.08 199 LIST OF VESSELS FITTED WITH BABCOCK & WILCOX BOILERS VESSELS BELONGING TO NA VIES Name No. of Boil- Indi- cated Horse- power Owner Gunboat Cruiser " Gunboat Torpedo- Cruiser ' Monitor Monitor Monitor Corvette Tender " Cruiser ' "Annapolis" Chicafjo" "Marietta" Boat " Sheldrake' Atlanta" . "Manhattan" . "Canonicus" "Mahopac" "Ellida" . Arlanza" . 'Alert" Monitor " Cheyenne " Sloop " Espiegle" . Fishery Control Steamer " Beskytteren " Cruiser "Cincinnati" Cruiser " Tacoma " Cruiser " Chattanooga " . Cruiser " Galveston " Cruiser " Raleigh " . Cruiser "Denver" . Cruiser " Des Moines " Cruiser " Cleveland " Second Class Cruiser " Challen- ger" Sloop "Odin" Battleship "Nebraska" . Cruiser " California " Cruiser "South Dakota". Cruiser " Milwaukee " Cruiser "vSt. Louis" Second Class Cruiser " Hermes " Battleship "Queen" First Class Cruiser "Cornwall" Cruiser " Maryland " Cruiser "West Virginia" Cruiser " Charleston " Monitor "Amphitrite" Battleship "Rhode Island" Battleship "New Jersey" Battleship "King Edward VII" Battleship "Dominion" . Battleship "Commonwealth" First Class Cruiser " Argyll " 6 6 6 8 6 6 6 12 4 12 i6 i6 i6 i6 12 1.5 24 i6 i6 i6 4 12 12 lO i6 i6 i6 1300 5400 1300 4000 3500 1500 1500 1500 700 150 1560 2450 1400 600 8490 5420 5400 5180 8160 6200 5400 4680 12500 1400 21900 29660 28840 24500 27480 1 0000 15000 22000 28470 26470 27510 1600 20630 23570 10800 18000 18000 16800 United States Navy United States Navy United States Navy British Navy United States Navy United States Navy United States Navy United States Navy Norwegian Navy Spanish Navy United States Navy United States Navy British Navy Royal Danish United States United States United States United States United States United States United States United States British British United United United United United British British British United United United United United United British British British British Navy Navy States States States States States Navy Navy Navy States States States States States States Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy Navy 201 VESSELS BELONGING TO NAVIES— Continued. No. Indi- Name of Boil- ers cated Horse- power Owner Battleship "Hindustan" i8 14400 British Navy Battleship "Connecticut' 12 20525 United States Navy First Class Cruiser "B lack Prince" . 20 18800 British Navy First Class Cruiser "Du ve of Edinburgh" 20 18800 British Navy Battleship "Louisiana" 12 21350 United States Navy Cruiser "Tennessee" 16 27430 United States Navy Cruiser "Washington" 16 27460 United States Navy Transport "Volga". 4 1600 Russian Navy Battleship "Vermont" 12 18250 United States Navy Gunboat "Dubuque" 2 1220 United States Navy Gunboat "Paducah" 2 1270 United States Navy Battleship "NapoU" 22 19000 Italian Navy Battleship "Britannia" 18 14400 British Navy Battleship "Hibernia" 18 14400 British Navy Battleship "Africa" 18 14400 British Navy Battleship "Indiana" 8 9740 United States Navy Monitor "Monterey" 4 5240 United States Navy Battleship "Minnesota" 12 20570 United States Navy Battleship "Kansas" 12 19760 United States Navy Battleship "Idaho" 8 14270 United States Navy Battleship "Mississippi" 8 13900 United States Navy Battleship "Lord Nelson 15 16750 British Navy Cruiser "Minotaur" 25 27000 British Navy Floating Dock "Dewey" 4 620 United States Navy Battleship "Roma" 18 20000 Italian Navy Battleship ""Dreadnought 18 23000 British Navy Cruiser "North Carolina 16 31035 United States Navy Cruiser "Montana" 16 28280 United States Navy Battleship "New Hamps' lire" 12 17270 United States Navy Fishery Control Steamer "Is- lands Falk" 2 1200 Royal Danish Navy Cruiser "Indomitable" 31 41000 British Navy Naval Academy I 400 United States Navy Naval Academy I 725 United States Navy Battleship "Bellerophon' 18 23000 British Navy Battleship "Superb" 18 23000 British Navy Customs Cruiser "Amapc i" I 450 Brazilian Navy Customs Cruiser "Baire' 2 1200 Cuban Navy Gunboat "Gloucester" 2 2000 United States Navy Battleship "Massachuset ts" 8 10400 United States Navy Battleship "Michigan" 12 16520 United States Navy Battleship " South Caroli na" 12 18360 United States Navy Armored Cruiser " Sarato ga" 12 17400 United States Navy Collier "Prometheus" 6 7500 United States Navy Collier "Vestal" . 6 7500 United Ftates Navy Battleship "Sao Paulo" 18 23500 Brazilian Navy 203 VESSELS BELONGING TO NAVIES— Continued. Name Battleship "Minas Geraes" Tug "Remorqueur No. 27" Cruiser "San Marco" Battleship "Capitan Prat" Battleship "St. Vincent" Battleship "Vanguard" . Refrigerating Vessel "Celtic" Battleship "Delaware" . Battleship "North Dakota" Cruiser "Baltimore" Cruiser "San Francisco" Tender "Simcoe" . Cruiser "Indefatigable" . Battleship "Utah" Floating Dock (Rio Janeiro) Training Vessel "Pomone" Gunboat "Tampico" Battleship "Colossus" Battleship "Florida" Floating Dock (Pola) Battleship "Maine" Battleship "Orion" Mine-laying Vessel "Lossc Battleship "Wyoming" Battleship "Arkansas" Battleship "Conqueror" Battleship "Thunderer" Battleship "Rivadavia" Battleship "Moreno" Cruiser "Australia" Cruiser "New Zealand" Floating Dock No. i Battleship "Giulio Cesare" Battleship "King George V" S, S. "Aberdeen" . Battleship "Ajax" . Training Ship "Essex" Battleship "Texas" Cruiser "Pittsburgh" Cruiser "Colorado" Water Tank & Salvage Vessel Gunl)oat "Morelos" Floating Dock for Submarines Floating Dock for Destroyers Gunboat "Chio" . Gunboat "Preveza" Gunboat "Touraque-Reize" Gunboat "Aidin Reize" . 18 Owner Brazilian Navy Italian Navy Italian Navy Chilian Navy British Navy British Navy United States Navy United States Navy United States Navy United States Navy United States Navy Canadian Government British Navy United States Navy Brazilian Navy British Navy Mexican Navy British Navy United States Navy Austrian Navy United States Navy British Navy Danish Navy United States Navy United States Navy British Navy British Navy Argentine Navy Argentine Xavy British Navy British Navy British Navy Italian Navy British Navy Canadian Government British Navy United States Navy United States Navy United States Navy United States Navy British Navy Mexican Navy British Navy British Navy Turkish Government Turkish Government Turkish Government Turkish Government 204 VESSELS BELONGING TO NAVIES— Continued. Name Battleship "^Mahomet Reshad V" ... Battleship " Rio de Janeiro" Gunboat "Bravo" . Battleship "New York" . Battleship "Iron Duke" . Battleship "Benbow" Battleship "No. 7" Cruiser "Deodoro". Cruiser "Floriano". Battle-Cruiser "Tiger" . Collier "Arethusa". Collier "Saturn" Battleship "Oklahoma" . Experimental Boiler Floating Dock Battleship "Queen Elizabeth" Battleship "Valiant" Test Boiler — Philadelphia Navy Yard Gunboat "Sacramento" . Gunboat "Wilmington" . Gunboat "Monocacy" Gunboat " Palos " . Fleet Oiler " Kanawha " . Battleship "Pennsylvania" Destroyer Tender "Melville" Battleship "Malaya" Battleship Battleship Battleship Floating Dock No. of Boil- ers 15 22 2 14 18 18 12 4 4 39 2 4 12 I I Indi- cated Horse- power 26500 32000 1700 30000 29000 29000 26000 3400 3400 85000 1700 1700 26000 1750 300 I 2500 2 1000 4 1900 2 800 2 800 4 5200 2 33000 2 4000 Owner Turkish Government Brazilian Navy Mexican Navy United States Navy British Navy British Navy Austro-Hungary Navy Brazilian Navy Brazilian Navy British Navy United States Navy United States Navy United States Navy French Navy British Navy British Navy British Navy United States Navy United States Navy United States Navy United States Navy United States Navy United States Navy United States Navy United States Navy British Navy British Navy British Navy British Navy Austrian Navy GOVERNMENT VESSELS OTHER THAN NAVY REVENUE CUTTERS No. Indi- Name of Boil- ers cated Horse- power Owner Revenue Cutter "Pamlico" I 900 United States Government Revenue Cutter "Itasca" 2 1620 United States Government Revenue Cutter "Bear" . I 800 United States Government Revenue Cutter "Snohomish" I 850 United States Government Revenue Cutter "Acushnet" 2 1500 United States Government 205 GOVERNMENT VESSELS OTHER THAN NAVY— Continued. No. Indi- Name of Boil- cated Horse- Name ers power Revenue Cutter "Tahoma" 2 1750 United States Government Revenue Cutter "Yamacraw" 2 1750 United States Government Revenue Cutter " Golden Gate" I 678 United States Government Revenue Cutter "Morrill" I 750 United States Government Revenue Cutter "Unalga" 2 1600 United States Government Revenue Cutter "Miami" 2 1600 United States Government Revenue Cutter " Calumet" I 620 United States Government Revenue Cutter "Manning" 2 2580 United States Government Revenue Cutter "McCulloch" 2 2Ht,0 United States Government ARAIY Tender "Ordnance" Tug "Gen. R. M. Randol" Transport "Burnside" United States Army United States Army United States Army VESSELS LM THE MERCANTILE MARL\E ON OCEAN CARGO AND PASSENGER SERVICE Name S. S. " Stadion " late " Nero S. S. "Cameo" S. S. "Orlando" . S. S. "Rollo". S. vS. "Truro" S. S. "Otto" . S. vS. " Dirigo" S. S. "Tasso" S. S. "Charles Nelson" S. S. "Kvichak" . S. S. "Martello" . S. S. "Santa Clara" S. S. "Mary D. Hume" S. S. "Rainier." S. S. "Fair Oaks" S. S. "Nome City" S. S. "Bowena" S. S. "Santa Ana" S. S. "Shelikof" S. S. "Coronado" S. S. "Santa Barbara" Xo. of Boil- ers Indi- cated Horse- power 500 1300 1200 1400 1500 1 500 650 1500 850 650 2500 1075 900 560 700 750 700 43i 4 3300 Dct Forencde Dampskibs-Selskab, Copen- hagen s. s. "San Ramon" 2 1250 C. J. Dodge, San Francisco, Cal. s. s. "Matsonia" . 6 8700 Matson Navigation Co. S. vS. "O.M.Clark" 2 1080 Charles H. Higgins s. s. "Mary Olson" 2 800 Olson & Mahony s. s. "Rosalie Mahonj^" . 2 800 Olson & Mahony s. s. "Daisy Putnam" 2 800 Freeman Steamship Co. s. s. "Solano" 2 800 Hart Wood Lumlier Co., San Francisco, Cal. s. s. "Celilo" 2 900 C. R. McCormick & Co., vSan Francisco, Cal. s. s. 14000 Canadian Pacific Ry. Co. s. s. " " 1 4000 1 Canadian Pacific Ry. Co. s. s. IJOOO 1 Union Steamship Co. of New Zealand VESSELS ON GREAT LAKES CARGO SERVICE Name No. of Boil- ers Indi- cated Horse- power Owner S. S. "Zenith City" 2 2000 Zenith Transit Co., Duluth, Minn. S. S. "Turret Crown" 2 1 1 00 Canadian Ocean & Inland Navigation Co., Ltd. S. s. "Turret Cape" 2 1 1 00 Canadian Ocean & Inland Navigation Co., Ltd. s. s. "Queen City" 2 2000 Zenith Transit Co., Duluth, Minn. s. s. "Crescent City" 2 2000 Zenith Transit Co., Duluth, Minn. s. s. "Empire City" 2 2000 Zenith Transit Co., Dukith, Minn. s. s. "Turret Chief" 2 1 100 Canadian Ocean & Inland Navigation Co., Ltd. s. s. "Turret Court" 2 1 100 Canadian Ocean & Inland Navigation Co., Ltd. s. s. "Superior Cit}^" 2 2000 Zenith Transit Co., Duluth, Minn. 208 VESSELS ON GREAT LAKES CARGO SERVICE— Continued. No. Indi- Name of Boil- cated Horse- Owner ers power S. S. "Alex. McDougall" 2 2500 Bessemer vSteamship Co., Cleveland, Ohio S. S. "Prcsque Isle" 2 2000 Presque Isle Transportation Co., Cleveland, Ohio S. S. "Mataafa" . 2 2000 Minnesota Steamship Co., Cleveland, Ohio S. S. "Maunaloa" . 2 2000 Minnesota Steamship Co., Cleveland, Ohio S. S. "Malietoa" . 2 2000 Minnesota Steamship Co., Cleveland, Ohio S. S. "John W Gates" . 2 2000 American Steel & Wire Co. S. S. "James J. Hill" . 2 2000 American Steel & Wire Co. S. S. "Isaac L. Ellwood" 2 2000 American Steel & Wire Co. S. S. "Wm. Edenborn" . 2 2000 American Steel & Wire Co. S. S. " Harvard " . 2 2300 Pittsburgh Steamship Co., Cleveland, Ohio S. S. "Lafayette" . 2 2300 Pittsburgh Steamship Co., Cleveland, Ohio S. S. "Princeton" . 2 2300 Pittsburgh Steamship Co., Cleveland, Ohio S. S. "Cornell" 2 2300 Pittsburgh Steamship Co., Cleveland, Ohio S. S. "Rensselaer" . 2 2300 Pittsburgh Steamship Co., Cleveland, Ohio S. S. "Paraguay" . 2 1500 Sun Co., Duluth, Minn. S. S. "Frank H. Peavey" 2 2000 Peavey Steamship Co., Duluth, Minn. S. S. "Geo. W. Peavey" . 2 2000 Peavey Steamship Co., Duluth, Minn. S.S. "F.T.Heffelfinger" 2 2000 Peavey Steamship Co., Duluth, Minn. S. S. "F. B.Wells" 2 2000 Peavey Steamship Co., Duluth, Minn. S. S. "James H. Hoyt" . 2 1700 Provident Steamship Co., Duluth, Minn. S. S. "Orlando M. Poe" . 2 2000 Pittsburgh Steamship Co., Cleveland, Ohio S. S. "Samuel F. B. Morse" 2 2000 Pittsburgh Steamship Co., Cleveland, Ohio S. S. "D. M. Clemson" . 2 1700 Provident Steamship Co., Duluth, Minn. S. S. "D. G. Kerr". 2 1700 Provident Steamship Co., Duluth, Minn. S. S. "J. H. Reed" 2 1700 Provident Steamship Co., Duluth, Minn. S. S. "H. G. Dalton" . 2 1 1 00 Great Lakes & St. Lawrence Transport Company S. S. "John Crerar" 2 HOC Great Lakes & St. Lawrence Transport Company S. S. "Geo. C. Howe" 2 1 100 Great Lakes & St. Lawrence Transport Company S. S. "John Sharpless" . 2 HOC Great Lakes & St. Lawrence Transport Company S. S. "Augustus B. Wolvin" 2 2500 Acme Steamship Company, Duluth, Minn. S. S. "James C. Wallace" 2 2500 Acme Steamship Company, Duluth, Minn. S. S. "Ward Ames" 2 2500 Acme Steamship Company, Duluth, Minn. S. S. "H. P. Bope" 2 2500 Acme Steamship Company, Duluth, Minn. OCEAN GOING AND RIVER DREDGES, ETC. Name No. of Boil- ers Indi- cated Horse- power Owner Dredge "Antleon" Dredge "Volga" 2 8 700 5600 N. S. W. Government. Builders, W. Simons & Co., Renfrew Russian Government. Builders, Societe J. Cockerill, Seraing 209 OCEAN GOING AND RIVER DREDGES, ETC.— Continued. No. Indi- Name of Boil- cated Horse- Owner ers power Dredge (Gold Washing) . I 100 AI. Alahozie, Paris Dredge "Lindon Bates" I 600 Indian Government. Builders, Sir W. G. Armstrong, Whitvvorth & Co., Newcastle- on-Tyne Dredge "Hercules" 4 2600 Queensland Government, Brisbane. Builders, Sir W. G. Armstrong, Whitworth & Co., Newcastle-on-Tync Dredge "Samson" 6 4900 Queensland Government, Brisbane. Builders, Sir W. G. Armstrong, Whitworth & Co., Newcastle-on-Tyne Dredge "Archer" . 4 2000 Queensland Government, Rockhampton. Builders, Sir W. G. Armstrong, Whit- worth & Co., Newcastle-on-Tyne Dredge "Texas City" I 1350 J. R. Myers, Houston, Texas Dredge "Branckcr" I 300 Mersey Dock & ILirliour Board Dredge (Gold Washing) I 200 Order of Marshall Sons & Co., Ltd., Gains- boro' Dredge "Solvay No. i " I 150 Solvay & Co., Paris Dredge "Uncle Sam" I 312 American Dredging Co., San Francisco Oil Pumping Plant I 93 Middle River Navigation Co., San Francisco Dredge "Tule Queen" I 80 J. C. Franks, San Francisco Dry Dock "Algiers" 4 620 United States Navy Dredge " " I 100 Rindge Nav. & Canal Co., California Icc-Breakcr "Montcalm" 4 4500 Canadian Government Dredge "Pioneer" . 2 600 Victorian Government Dredge "San Pedro" 2 366 U. S. Engineers' Dcpt. Dredge "Jacksonville" . 2 306 U. S. Engineers' Dcpt. Dredge "Tethys" 2 900 New South Wales Government Dredge "Foyers" 4 2400 Indian Government, Bengal Dredge " " 2 432 South Pacific Co., San Francisco Dredge "Lake Simcoe" I 300 Lake Simcoe Dredging Companj' Dredge "Elwood" . 2 520 South Australian Government Dock (Floating) 2 1000 Mitsu Bishi Dockyard, Japan Dredge " " 2 1400 For Sudan Dock (Floating) 3 234 Cia Peruana de Vaporcs y Dique del Callao Dock (Floating) 2 118 Pcnarth Dock Company Dredge "Maryland" I 700 American Dredging Company Hopper Dredge "Kitsumaru No. I " 2 2000 L^raga Dock Co., Japan Suction Dredge "New Orleans" 4 2500 United States Government (War) Hopper Dredge " " 2 2000 Uraga Dock Co., Japan Dredge "Lyons" . 2 2000 Crowell-Sherman-Staltcr Co., Lyons, N. Y. Dredge No. 15 2 1500 P. S. Ross, Inc., Jersey City, N. J. Dredge "Geo. W. Allen" I 1350 Florida East Coast Ry. Floating Crane 500 Brazilian Government VESSELS ON HARBOR AND RIVER PASSENGER SERVICE Name No. of Boil- S. S. " Noref jeld " . S. S. "Ainasis" late "Moham- med AH" P. S. "Rameses" P. S. "Konstantin Arzibouchev' S. S. "Zaritzen" P. S. "Ooonas" P. S. "Berusa" P. S. "Serapis" P. S. "Boyki" P. S. "Lichay" P. S. " " Fireboat "W. S. Grattan" P. S. "Ane" P. S. " Barquisemeto " P. S. " Crocodile" Ferryboat "San Jose" Ferryboat "Yerba Buena" P. S. "Bhagabatti" Ferryboat "San Francisco" Ferryboat "Richmond" Ferryboat "Manhattan" Ferryboat "Brooklyn" Ferryboat "Queens" Ferryboat "Bronx" S. S. "Vaucluse" S. S. "Pelican" P. S. "Brighton" . Ferryboat "Pittsburgh" Ferryboat "St. Louis" Ferryboat "Hammonton" Fireboat "James Duane" Fireboat "Thos. Willett" S. S. "^— " P. S. "Gunga" P. S. "Sarasvati" Fireboat "Cornelius W. Law- rence" Ferryboat " Camden " Fireboat "David Scannel" Fireboat "Dennis T. Sullivan" Ferryboat "Guanabacoa" Ferryboat "No. i". Ferryboat ' ' Washington Indi- cated Horse- power 225 375 600 300 125 650 125 350 350 60 900 350 100 1200 1650 1650 2 450 2 3000 4 4000 4 4000 4 4000 4 4000 4 4000 I 500 I 100 2 800 4 3080 4 3080 2 1 100 2 1650 2 1650 I 100 2 500 2 500 2 1250 2 1 1 00 2 1800 2 1800 2 700 2 700 2 1 1 00 Owner Akers Mek., Christiania Thos. Cook & Son, Cairo Thos. Cook & Son, Cairo Nevsky Mec. Works, St. Petersburg Russian Government Thos. Cook & Son, Cairo Sevecke Steamship Company Thos. Cook & Son, Cairo Russian Trade & Navigation Co., Odessa Russian Trade & Navigation Co., Odessa Societe Generale Mercantile, Paris City of Buffalo, N. Y. Nadejda Steamship Co., St. Petersburg The Bolivar Railway Company Bengal Ry. (Indian Government) San Francisco, Oakland and San Jose Rail- way Company San Francisco, Oakland and San Jose Rail- way Company East India Railway Company San Francisco, Oakland and San Jose Rail- way Company City of New York City of New York City of New York City of New York City of New York Watson's Bay & South Shore Steam Ferry Company Adelaide S. S. Company Port Jackson Co-operative S. S. Co., Sydney Pennsylvania Railroad Company Pennsylvania Railroad Com.pany Pennsylvania Railroad Company City of New York City of New York Yokohama Engine & Iron Works, Japan East India Railway Company East India Railway Company City of New York Pennsylvania Railroad Company City of San Francisco City of San Francisco Havana Central Railroad Company North Vancouver City Ferries, Ltd. Pennsylvania Railroad Company . '^M O Q 5 y. 212 VESSELS ON HARBOR AND RIVER PASSENGER SERVICE— Continued. No. Indi- Name of Boil- cated Horse- Owner ers power Ferryboat "Greycliffe" . I 300 Watson's Bay & South Shore Ferry Company Fireboat "Engine No. 31 " I 648 City of Boston Ferryboat "San Pedro" . 4 33II Atchison, Topeka & Santa Fe Company Ferryboat "Wildwood" . 2 1 1 00 Pennsylvania Railroad Company Ferryboat "Angel Island" I 675 United States Government (Department of Commerce) Paddle Steamer " " . I 125 For Columbia Ferryboat " No. 2 " . 2 700 North Vancouver City Ferries, Ltd. Fireboat "Engine No. 44" I 950 City of Boston Ferryboat "Alameda" 4 3380 South Pacific Railway S. S. "Kiang Wha" 4 3000 China Merchants Steam Navigation Com- pany S. S. "Champion" I 120 La Compagnie Maritime & Industrielle de Lewis, Quebec Ferryboat "Edward T. Jeffrey " 4 4430 Western Pacific Railway Fireboat "Wm. J. Gaynor" 2 1260 City of New York Ferryboat "Cincinnati" 2 1200 Pennsylvania Railroad Company Ferryboat "Bridgeton" . 2 1 100 Pennsylvania Railroad Company Ferryboat " Salem " 2 1 100 Pennsylvania Railroad Company Ferryboat " " . 3 2000 City of New York Ferryboat "Santa Clara" 4 3380 Southern Pacific Company S. S. " " 1400 Holland S. S. "Vanlmhoff" 1600 Holland S. S. "Pynacker Hardyk" 1600 Holland S. S. "Chauncey Maples" 200 Universal Mission to Central Africa STEAM TUGS Name Tug "Rodney" Tug "Edna G. " Tug "Duke" . Tug "Benbow" Tug "Pier" Tug "Hotspur" Tug "Sirdar" Tug "Scott" Tug "Holland" Tug "A. J. Beardsley' Tug "Dauntless" Tug "A. H. Payson" Tug "No. 2 Ostend" Tug "Arabs" No. of Boil- Indi- cated Horse- ers power I 200 I 550 I 120 I 200 I 400 2 800 2 800 2 800 2 800 I 450 2 1000 I 925 I 400 I 925 Owner S. Williams & Sons, Dagenham, Eng. Duluth & Iron Range Ry. Co., Port Duluth S. Williams & Sons, Dagenham, Eng. S. Williams & Sons, Dagenham, Eng. New York City Dock Dept. London & India Docks Joint Committee London & India Docks Joint Committee London «S: India Docks Joint Committee London & India Docks Joint Committee Rodgers, McMullen & McBean, New York Merchants Tug Boat Co., San Francisco Santa Fe Terminal Co., San Francisco Belgian Government Pacific Mail S. S. Co., San Francisco 213 STEAM TUGS— Continued. Name Tug "Power" Tug "E. P. Ripley" Tug "Navigator" Tug"Ajax" Tug "Virgil C. Bogue' Tug"Alacrty" Tug "Johnstown" Tug "Wilmington" Tug "Harrisburg" . Tug "Beam" Tug "Beverley" Tug "Walbrook" . Tug "Teir-el-Mina" Tug "Ludwig Wiener" Tug "Manhattan" Tug "Kurer" No. of Boil- Indi- cated Horse- power lOOO 900 1300 825 925 II50 850 850 933 1000 1000 1000 600 2400 1090 150 Owner London & India Docks Company Atchison, Topeka & Santa Fe Railway Associated Oil Co., San Francisco Southern Pacific Co., San Francisco Western Pacific R. R. Company Howard Smith & Company Pennsylvania Railroad Company Pennsylvania Railroad Company Pennsylvania Railroad Company Port of London Authority Port of London Authority Port of London Authority Egyptian Ports & Lighthouses Administra- tion South African Railways (Table Bay Harbor Dcpt.) City of Xew York Denmark YACHTS No. Indi- Name of Boil- ers cated Horse- power Owner S. Y. "Reverie" I 275 F. G. Bourne, New York S. Y. "Eleanor" I 200 D. Lancaster, .Surrey, Eng. S. Y. "Trophy" I 250 E. H. Bennett, Xew York S. Y. "Seneca" I 450 Chas. Fletcher, Providence, R. I. S. Y. "Magpie" I 80 Thomson & Campbell S. Y. "Onora" I 300 James H. Rosenthal S. Y. "lolanda" 2 1350 Morton F. Plant, New York S. Y. "Idalia" I 800 W. D. Hoxie, New York S. Y. "Sialia" 2 1400 J. K. Stewart, New York S. Y. "Cyprus" 4 3500 D. C. Jackling, Salt Lake City 214 INDEX A Acidity of boiler-water, and methoil of neutralizing .... Air in feed-water as causing corro- sion "Alert," U.S.S., test of boiler . Analysis of chimney gases by Orsat apparatus Analysis of chimney gases: U. S. S. "Cincinnati" test . U. S. S. " Wyoming," coal test. U. S. S. " Wyoming," oil test . Analysis of coal for U. S. S. "Wy- oming" test .... Analysis of sea water .... "Antilles," S. S. Test of machinery .... Auxiliary machinery, steam con- sumption of, S. S. "Penn- sylvania" 123 136 73 161 184 199 184 119 105 146 Babcock & Wilcox Boilers — Continued In U. S. S. "Cincinnati" In S. S. "Pennsylvania" Test boiler Babcock & Wilcox dredge boiler . Baume scale, density of oil by . Boilers, Babcock & Wilcox, Advan- tages of Ideal, charcateristics of. Scotch, economic performance of Steam, efficiency of . . . Boiler tests, Scotch .... Boiler, water-tube, history of Water-tube, weight and space for various makes Burner, mechanical atomizing (Pea- body) , of Babcock & Wilcox Co 151 143 179 41 64 9 29 58 70 58 II 39 67,69 B Babcock & Wilcox boilers: Adequate amount of water . . 32 "Alert" design (1899) ... 18 Care of 130 Circulation in 23, 89 Combustion in furnace of . . 23 Description of 21 Designs of 1856 and 1868 . . 13 Designs of 1873 and 1881 . . 14 Design of 1895 16 Design of 1896 19 Development of 13 End view, showing cleaning doors 20 Front view showing drum fit- tings 24 Lightness with adequate scant- lings ....... 32 Side casing, construction of . 26 Babcock & Wilcox boilers in steam- ships, plans of: "Alert," U. S. S 134 "Denver," U. S. S. and Class. 92 Lake Cargo Steamer ... 138 "Zenith City," S. S. ... 17 Babcock & Wilcox boilers, tests of: "Alert," U. S. S 136 "Cincinnati," U. S. S. . . . 151 Experimental marine boiler . 135 "Gates, John W.," S. S. . . 165 Lake Cargo Steamers . . . 141 "McDougall, Alex," S. S., . . 147 "Pennsylvania," S. S. . . . 143 Sea-going dredge 163 " Wyoming," U. S. S. with coal 169 " Wyoming," U.S. S. with oil . 187 Babcock & Wilcox boilers, weight of: InU. S. S. "New Hampshire" 39 InU. S. S. "Utah" .... .39 InU. S. S. "Alert" .... 136 Calorimeter for coal, the Mahler bomb 71,72 For determining dryness of steam 88 Care of Babcock & Wilcox boilers . 130 Characteristics of ideal boiler . . 29 "Cincinnati," U. S. S., test of boiler 151 Circulation in Babcock & Wilcox boiler 23, 89 Cleaning panel 27 Coal, description of various classes . 47 Heat values of 59 Coal and oil, relative cost and heat- ing effect 66 Combustion of coal, conditions for efficiency 55 Combustion in furnace of Babcock & Wilcox boiler. ... 23 Corrosion, causes and preventive measures 119 "Creole," S. S. Test of machinery . 105 D Description of Babcock & Wilcox boiler 21 Dredge boiler, Babcock & Wilcox . 41 Dredge, sea-going. Test of boiler . 163 Drum fittings. Babcock & Wilcox boiler 24 Drum head, forged steel .... 25 Durability of Babcock & Wilcox boilers, examples of . . 115 Dusting panel 27 E Economy due to feed-water heating . 97 Economy due to superheated steam in marine practice ... 104 Economy of evaporation ... 33 Economy of space 33 215 Efficiency, high, of Babcock & Wil- cox boiler, reasons for . . 78 Efficiency of steam boilers ... 70 Evaporation, equivalent, from and at, 212° Fahr. . . . 86, 87 Experimental marine boiler, test of 135 Feed- water heating, economy due to 97 Firing, methods for various fuels . 130 Forcing, severe, ability to stand . 35 "From and at" 212° Fahr., equiva- lent evaporation . . . 86, 87 Fuel, its combustion and heat value 47 Fuel, oil as 63 Fuel oils, calorific value, density, etc. 67 Fuels, solid, chemical composition of 51 Gases, chimney, analysis of, ])y Orsat apparatus 73 Gases, chimney, analysis of: U. S. S. "Cincinnati" test . . l6l U. S. vS. " Wyoming," coal test 184 U. S. S. " Wyoming," oil test . 199 Gases of combustion, temperature of, in Babcock & Wilcox Boiler 154 "Gates, John W.," S. S. Test of boilers and machinery . 165 H Header, forged steel 21 Headers, strength of .... 30 Heat-balance, record of, for tests of U. S.S. "Wj^oming" boiler 185 Heating feed-water, economy due to 97 History of water-tube boiler ... 11 " Idalia," Steam Yacht, test of ma- chinery 107 Impeller or air register .... 68 Interchangcability of parts ... 35 K "Kansas," U. S. R. Test of machinery .... 107 L Machinerv, tests of — Continued "Creole," S. S "Gates, John W.," S. S. . . "Idalia," Yacht .... "Kansas," U. S. S. ... Lake Steamers "McDougall, Alex.," S. S. . . "Michigan," U. S. S. . . . "Alomus," S. S "New Hampshire," U. S. S. . "Pennsylvania," S. S. . "South Carohna," U. S. S. Melting points of metals .... "AIcDougah, Alexander," S. S. Test of boilers and machinery . Melville, Admiral List of characteristics of ideal boiler "Michigan," U. S. S. Test of maclnnerv . Model of Babcock & Wilcox Boiler full size sectional . Moisture in steam, determination of "Alomus," S. S. Test of machinery . Alonitors, U. S., reboilering . Mosher boiler, weight and space oc- cupied in U. S. S. "Kear- sarge" N "New Hampshire," U. S. vS. Test of machinery .... Normand boiler, weight and space occupied in U. S. S. " Chester," "Salem," and "Trippe" O Oil and coal, relative cost and heat- ing effect Oil, density of, on Baume scale . Oil-burner, Babcock & Wilcox . Oil Fuel Oils, fuel, calorific value, specific gravity, etc Oil fuel, liigh capacity'' test on "Ok- lalioma" boiler .... Oil-fuel tests on boiler for U. S. S . " Wyoming" .... Orsat apparatus for analyzing chim- ney gases 105 165 107 107 141 147 107 105 107 143 107 61 147 31 107 118 95 I "5 113 39 107 39 66 64 67,69 63 67 65 187 73. Lake Steamers, 6500 ton Test of machinery .... Lightness of Babcock & Wilcox Boiler Lime, use of, to prevent corrosion . Liquid fuel, advantages of . . . List of vessels fitted with Babcock & Wilcox Boilers .... M Machinery, tests of "Antilles," S. S. 141 32 121 63 201 105 "Pennsylvania," S. S. Test of boilers and machinery R Raising steam quickly .... Raising steam, time necessary for, 137, 157, Register, air (impeller) .... "Reverie," Steam Yacht. " Reverie," boiler of Rugged construction and ability to stand abuse .... 143 33 175 68 15 51 35 216 S page; Safety against explosion .... 37 Sea-water, analysis of .... 119 Side casing, Babeoek & Wilcox boiler 26 Soda for neutralizing acidity . . 123 "South Carolina," U. S. S. Test of machinery .... 107 Steam calorimeter 88 Steam consumption of auxiliary machinery, S. S. "Penn- sylvania" 146 Steam, properties and laws of gene- ration 80 Steam, saturated, table of pressures, temperatures, etc. ... 81 Steam, saturated, below atmospheric pressure, table .... 83 Steam, superheated, economy of . 104 Stevens' Boat 11 Stevens, John, boiler 11 Stevens, John Cox, boiler ... 12 Superheated steam, economy due to, in marine practice ... 104 Superheater, Babcock & Wilcox . 102, 103 T Tables Analysis of chimney gases, 161, 184, 199 Analysis of coal and ash, U. S. S. "Wyoming" .... 184 Analysis of sea-water ... 119 Calorific value, specific gravity, etc., of fuel oils .... 67 Chemical composition of solid fuels 51 Cost, relative, of coal and oil . 66 Cylindrical boilers, performance of 58 Density of oil 64 Factors of Evaporation . . 87 Feed-water heating, economy of 97 Heat balance, U. S. S. " Wyom- ing," with coal .... 185 Heating effect, relative, of coal and oil 66 Heat values of coal .... 59 List of vessels fitted with Bab- cock & Wilcox Boilers . 201 Melting points of metals . . 61 Notable temperatures of water 85 Raising steam, record of, 137, 157, 175 Saturated steam, properties of . 81 Saturated steam, below atmos- phere 83 Steam consumption, auxiliary machinery 146 Superheated steam, merchant vessels 105 Superheated steam, U. S. naval vessels 107 Superheated steam, Yacht "Idalia" 107 Temperature of fire .... 61 Tables — Continued Water between 32° and 212° Fahr Weight of water above 200° Fahr Weight of water, boiler of U. S. S. "Cincinnati" Weight and spare of various water- tube boilers . Temperature of fire Temperature of gases in Babcock & Wilcox Taoiler .... Tests of Babcock & Wilcox boilers: "Alert," U. S. S "Cincinnati," U. S. S. . . . Experimental marine boiler . "John W. Gates," S. S. Lake Cargo Steamers . "AIcDougall, Alex.," S. S. . . "Pennsylvania," S. S. . Sea-going dredge .... "Wyoming," U. S. S., with coal "Wyoming," U. S.S., with oil Tests of Scotch boilers .... Thornycroft boiler, weight and space occupied in U. S. S. "Burrows" and " Terry". 85 83 157 39 61 154 136 151 135 165 141 147 143 163 169 187 58 39 Vessels fitted with Babcock & Wil- cox boilers, list of . . . 201 W Water, adequate amount of, in Bab- cock & Wilcox boiler . . 32 Water between 32° and 212° Fahr., table of weight and heat units 84 Water, test for corrosiveness of . . 124 Water, weight of, at various tem- peratures above 200° Fahr. 83 Weight and space for various water- tube boilers 39 Weight of Babcock & Wilcox boil- ers . . 39, 136, 143, 151, 179 Weight of water in boiler of U. S. vS. "Cincinnati," at various heights 157 White-Forster boiler, weight and space occupied in U. S. S. "Maryant" .... 39 " Wyoming," U. S. S. Test of boiler with coal as fuel. 169 Test of boiler with oil as fuel . 187 Y Yarrow boiler, weight and space oc- cupied in U.S. S. "Sterrett" 39 Zinc, use of, to prevent corrosion 124 217 INDEX TO ILLUSTRATIONS A PAGE 'Acushnet," U. S. Revenue Cutter . 172 'Africa," H. M. Battleship ... 188 'Alert," U. S. S., arrangement of boilers 134 'Adeline Smith," Lumber Steamer . 120 'Anteleon," Hopper Dredge . . 30 'Argyll," H. M. Armored Cruiser . 196 'Arkansas," U. S. Battleship . . 10 "Edna G.," Steam Tug Expander, tube Fire room of U. S. S. "St. Louis" "Florida," U. S. Battleship . . 131 132 74 22 B Babcock & Wilcox Boiler Circulation in 89 Design of 1868 13 Design of 1873 and 1881 . . 14 Design of 1895 16 Design of 1896 19 "Alert," design .... 20,56,153 Dredge design 42, 43 End view, cleaning doors . . 20 Front view 24 In U. S. Naval Oil-Fuel Testing Plant 65 Of U. S. S. "Cincinnati" . . 153 "Bear," U. S. Revenue Cutter . . 172,190 Burner for Liquid Fuel .... 69 "Burnside," U. S. Army Transport 112 Gas Analysis, Orsat apparatus for . "Grattan, W. S.," Fire Boat and Ice Breaker, Buffalo "Greenore," Cross-channel Steamer H "Hammonton," Ferryboat of Penn- sylvania Railroad . Header, forged steel " Hume, Mary D.," Arctic Whaler . I 73 94 168 176 21 57 68 Impeller for liquid-fuel burner . Installing boilers in vessels, methods of 28, 164 "Island's Falk," Danish Fishery Steamer 103 Calorimeter, coal, Mahler's bomb . 72 Calorimeter, steam 91 "Cincinnati," U. S. Cruiser . 152 "Cincinnati," U. S. S., boiler of . 153 "Charleston," U. S. First Class Cruiser 38 Circulation in Babcock & Wilcox boiler 89 "City of Nanaimo," Steam Packet . 116 Cleaning doors 20 "Colossus," H. M. Battleship . . 194 "Connecticut," U. S. Battleship . 40 "Creole," S. S. of Southern Pacific Co 54 D December on Lake Superior . . 79 "Delaware," U. S. Battleship . . 48 "Denver," Class, U. S. Navy Arrangement of boiler rooms . 92 " Dewey," U. S. Floating Dry Dock 36 Dredge, "Anteleon" 30 "Lyons" 46 " New Orleans" 45 For Volga River .... 44 Dredge design of Babcock & Wilcox boiler 42,43 Drum fittings 24 Drum-head, forged steel .... 25 Dusting-door 27 Dusting-panel 27 "Joaquin del Pielago," S. S. . . 202 K "Kiang-Wha," S. S. China Merchant Xav. Co. . . 177 Lake Cargo Steamers Arrangement of boilers ... 138 "Lazaro,A.," S. S 198 "Lord Nelson," H. M. Battleship . 50 "Louisiana," U. vS. Battleship . . 40 "Lyons," Dredge for N. Y. State Barge Canal .... 46 "McDougall, Alexander," Largest Whaleback Steamer . . 148 M Mahler's Bomb Calorimeter . . 72 "Mahomet AH," Nile Steamer . 98 "Manhattan," N. Y. Municipal Ferryboat 128 Man-hole plate 25 "Manning," U. S. Revenue Cutter. 172 "Matsonia," S. S. Fire-room of . 178 "Michigan," U. S. Battleship . . 108 "Milwaukee," U. S. First Class Cruiser 38 218 "jNIinas Geracs," Brazilian Battle- ship "Minnesota," U. S. Battleship . " Minotaur," H. M. Armored Cruiser "Montana," U. vS. Armored Cruiser " Montcalm," Canadian Ice Breaker "Moreno," Argentine Battleship N "Napoli," Italian Battleship "Nelson, Charles," Steam Packet . "New Hampshire," U. S. Battle- ship "New Orleans," U. S. Army Dredge "New York," U. S. Battleship Non-conducting covering in side casing "North Carolina," U. S. Armored Cruiser " North Dakota," U. S. Battleship . O Oil-Fuel, Babcock & Wilcox boiler for, at Naval Testing Plant Oil-Fuel, burner for Orsat apparatus for gas analysis P Plug extractor "Pomone," H. M. Gunboat "Princess Victoria," Cross-channel Steamer R Rail shipment of boilers . "Rainier," Steam Packet "Raleigh," U. S. Cruiser "Reverie," Steam Yacht "Reverie," boiler of . "Rivadavia," Argentine Battleship Riveted joint "Riviera," Cross-channel Steamer "Roma," Italian Battleship " St. Louis," U. S. First Class Cruiser "St. Louis," U. S. S., Fire-room of "San Marco," Italian Armored Cruiser "San Pedro," Ferryboat of A. T. S: S. F. Railway .... "Santa Anna," Steam Packet . "Scannell, David," Fire Boat, San Francisco "Shelikoff," Steam Whaler . . . vShipmentof boilers by rail . Ships fitted with Babcock & Wilcox Boilers: "Acushnet," U. S. Revenue Cutter "Africa," H. M. Battleship "Argyll," H. M. Armored Cruiser "Arkansas," U. S. Battleship . 96 212 100 49 180 62 122 132 150 45 26 49 48 65 69 73 131 192 77 82 152 15 15 62 25 52 34 38 74 90 174 181 160 125 77 172 188 196 10 Ships fitted with Babcock & Wilcox Boilers — Continued "Anteleon," Sea-going Dredge. 30 "Bear," U. S. Revenue Cutter 172, 190 "Burnside," U. S. Army Trans- port 112 "Charleston," U. S. First Class Cruiser 38 "Cincinnati," U. S. Cruiser . 152 "Colossus," H. M. Battleship . 194 "Connecticut," U. S. Battle- ship 40 "Creole," Passenger and Freight Steamer 54 "Delaware," U. S. Battleship . 48 "Edna G.," Steam Tug . . 131 "Florida," U. S. Battleship . 22 "Grattan, W. vS.," Fire Boat . 94 "Greenore," Cross-channel Steamer 168 "Hammonton," Pcnna. R. R. Ferryboat 176 "Hume, Mary D.," Arctic Whaler 57 " Island's Falk," Danish Fishery Steamer 103 "Kiang-Wha," Chinese Mer- chant Steamer .... 177 " Lazaro A.," Merchant Steamer 198 "Lord Nelson," H. M. Battle- ship 50 " Louisiana," U. S. Battleship . 40 "McDougall, Alex.," Whale- back Steamer .... 148 "Mahomet Ali," Nile Steamer 98 "Manhattan," New York City Ferryboat 128 "Manning," U. S. Revenue Cutter 172 "Michigan," U. S. Battleship . 108 "Milwaukee," U. S. First Class Cruiser 38 "Minas Geraes," Brazilian Bat- tleship 96 "Minnesota," U. S. Battleship . 212 "Minotaur," H. M. Battleship . 100 "Montana," U. S. Armored Cruiser 49 "Montcalm," Canadian Ice Breaker 180 "Moreno," Argentine Battle- ship 62 "Nanaimo, City of," Steam Packet . " 116 "NapoH," Italian Battleship . 122 "Nelson, Chas.," Steam Packet 132 "New Hampshire," U. S. Bat- tleship 150 "New Orleans," U. S. Army Dredge 45 "NewYork,"U.S. Battleship . 8 "North Carolina," U. S. Ar- mored Cruiser .... 49 "North Dakota," U. S. Battle- ship 48 "Pielago, Joaquin del," Mer- chant Steamer .... 202 "Pomone," H. I\I. Gunboat . 192 219 Ships fitted with Babcock & Wilcox Boilers — Continued "Princess Victoria," Cross- channel Steamer "Rainier," Steam Packet . "Raleigh," U. S. Cruiser . . "Reverie," Steam Yacht "Rivadavia," Argentine Battle- ship "Riviera," Cross-channel Steamer "Roma," ItaHan Battleship "Saint Louis," U. S. First Class Cruiser "Santa Anna," Stem Packet . "San Marco," Italian Armored Cruiser "San Pedro," Ferryboat, Santa F^ Railway .... "Scannell, David," Fire Boat, San Francisco .... " vShelikoff," Steam Whaler "Smith, Adeline," Lumber Steamer "South Carolina," U. S. Battle- ship "Sullivan, Dennis T.," Fire Boat "Superior City," Lake Steamer "Tennessee," U; S. Armored Cruiser "Texas," U. S. Battleship . "Unalga," U. S. Revenue Cut- ter "Utah," U. S. Battleship . . "Vanguard," H. M. Battleship "Warilda," Australian Mer- chant Steamer .... "Washington," U. S. Armored Cruiser "Wolvin, Augustus B.," Lake Steamer .... "Wyoming," U. S. Battleship "Yamacraw," U. S. Revenue Cutter " Zenith City," Lake Steamer Side casing, construction of . "vSouth Carolina," U. S. Battleshi] Stevens, John, Early Steamer . Stevens, John, boiler ITO 82 15 62 52 34 38 181 90 174 160 125 120 108 162 84 156 8 172 22 200 142 156 126 10 172 114 26 108 II II Stevens, John Cox, boiler "Sullivan, Dennis T.," Fire Boat, San Francisco .... "Superior City," Lake Steamer. Superheater, Babcock & Wilcox Temperature of gases in passage through boiler .... "Tennessee," U. S. Armored Cruiser Testing Plant at Babcock & Wilcox Works for coal as fuel Testing Plant at Babcock & Wilcox Works for oil as fuel . "Texas," U. S. Battleship . U "Unalga," U. S. Revenue Cutter "Utah," U. S. Battleship . . "Vanguard," H. M. Battleship . W "Warilda," S. S., in Australian trade "Washington," U. S. Armored Cruiser Wilcox, Stephen, boiler of 1856 . "Wolvin, Augustus B.," Lake Steamer Works, Babcock & Wilcox: Bayonnc, N. J Barberton, Ohio Renfrew, Scotland . Paris, France ( )])erhausen, Germany " Wyoming," U. S. Battleship . Y "Yamacraw," U. S. Revenue Cutter Z "Zenith City," Lake Steamer . 12 162 84 154 156 170 186 172 142 156 13 126 2 3 4 5 5 10 172 114 The Knickerbocker Press (G. P. PUTNAM'S Sons) New York Jm^MMi'MiMkm^ 868799 THE UNIVERSITY OF CALIFORNIA LIBRARY