.OH-' ENGINES. UC-NRLF REESE LIBRARY OF THE UNIVERSITY OF CALIFORNIA. Deceived ,190 . Accession No. ^2934 m Class. No. .>'.: ; THE DESIGN AND CONSTRUCTION OF OIL ENGINES WITH FULL DIRECTIONS FOR ERECTING, TESTING, INSTALLING RUNNING AND REPAIRING INCLUDING DESCRIPTIONS OF AMERICAN AND ENGLISH KEROSENE OIL ENGINES By A. H. GOLDINGHAM, M.E. Fully Illustrated OF THB I UNIVERSITY NEW YORK : SPON & CHAMBERLAIN, 12 CORTLANDT ST. LONDON : E. & F. N. SPON, LTD., 125 STRAND 1900" Entered According to Act of Congress in the Year 1900, by ARTHUR HUGH GOLDINGHAM In the Office of the Librarian of Congress, Washington, D. C. THE BURR PRINTING HOUSE, FRANKFORT AND JACOB 8T8. , N. Y. , U. 6. A. PREFACE THIS work has been written with the intention of supplying practical information regarding the kero- sene or oil engine, and in response to frequent re- quests received by the writer to recommend such a book. Whilst many works have been published on the subject of gas engines, some of which refer to or describe the working of the oil engine, no other book, it is believed, is devoted entirely to the oil engine in detail. The work, it is hoped, will be found useful to the draughtsman, the engine attendant, as well as to those who own or are about to install Oil Engines. The classification of vaporizers has been adhered to as made some few years ago, and a representative engine with each type is described. The matter on design and construction is founded on practical experience, the formulae, it is believed, being in accordance with the best modern practice. Chapter III. on Testing "is based on the writer's personal experience in the testing-room. iv PREFACE. The writer is particularly indebted to Mr. George Richmond for many valuable suggestions, and also for reading the proof-sheets, and he wishes to acknowledge assistance from many firms, amongst which may be mentioned Ingersoll Sargeant Drill Company for Table III., Mr. Frank Richards for Table II., The De La Vergne Company for Table IV., London Engineer, Tables V. and VI. Table I. is partly taken from Mr. William Norris's book on the Gas Engine, and Tables VII., VIII., IX., and X., at the end of the book, relating to different oils, are taken (with per- mission) from Mr. Boverton Redwood's valuable work on Petroleum. And to the Engineering News for permission to use Figs. 44^ and 44^. The Crosby Steam Gauge Company have also supplied informa- tion relating to the indicator and planimeter. A. H. GOLDINGHAM. NEW YORK, November i, 1900. CONTENTS. CONTENTS. CHAPTER I. INTRODUCTORY. PAGE Historical Classification of Oil Engines Various Vaporizers Different 'Igniting and Spraying De- vicesThe Different Cycles of Valve Movements 1-19 CHAPTER II. ON DESIGNING OIL ENGINES. Simplicity in Construction and Arrangement of Parts Comparison of Oil and Gas Engines Cyl- inders, Different Types Cylinder Clearance Crank-shaft, Dimensions and Formulae Balanc- ing of Crank-shafts Described Connecting-rods, Strengths, etc. Piston, Piston-rings Piston speed Fly-wheels, Formula for Air and Ex- haust Cams Cylinder Lubricators Valves and Valve-boxes Velocity of Air through Valves Crank-shaft Bearings Proportions of Engine Frame Crank-pin Dimensions Valve Mechan- isms, Gearing and Levers Governing Devices Exhaust Bends Oil-supply Pump Oil-tank and Filter Comparison of Horizontal and Vertical Type Engines, with Advantages of Each Two- cylinder Engines Discussed Assembling of Oil- engines Scraping in Bearings Fitting of Piston and Piston-rings Fitting Connecting-rod Bear- ings Fitting Air and Exhaust Valves Test- ing Water-jackets Fly-wheel Keys Oil-supply Pipes Cylinder Made in. Two or More Parts, . . 20-58 VI CONTENTS. CHAPTER III. TESTING ENGINES. PAGE Object of Testing Comparison with Steam-engines Different Records to be Taken Diagram for set- ting Valves Preparing for Test Heating of Va- porizer Starting Difficulties of Starting Com- pression, How to Test Leakage of Valves and Cylinder Lubrication of Piston and Bearings Easing Piston Synonymous Terms for Power De- veloped Indicated Horse-power Brake, Horse- power Indicator Fully Described Reducing Motions Planimeters Indicator-cards described in Detail and Analyzed Defects as Shown by Indicator How to Remedy Same Early and Late Ignition, How to Alter The Compression and Expansion Lines Choked Exhaust Mean Effective Pressure, How to Increase Back Pres- sure of Exhaust Tachometers Fuel-consump- tion Test Fully Described Mechanical Efficiency Thermal Efficiency Table of Disposition of Heat Valve Diagram Exhaust Gases Complete and Incomplete Combustion Testing the Flash- point of Kerosene Viscosometer, 59-95 CHAPTER IV. COOLING WATER-TANKS AND OTHER DETAILS. Water Connections Capacity of Tanks Required Gravitation System of Circulation Water-pumps Connection to City Water Main Temperature of Outlet Water Emptying Pipes in Frosty Weather Salt Water Exhaust Silencers Brick Pit, How to Construct Exhaust-Gas Deodorizer, CONTENTS. Vll PAGE How to Connect Connecting Circulating Water to Exhaust-pipe Self-starters, Why Necessary Utilizing Waste Heat of Exhaust Gases and of Cooling Water, Different Methods Exhaust Temperature, 96-110 CHAPTER V. OIL ENGINES DRIVING DYNAMOS. Isolated Plants Advantages of Oil Engines as Com- pared with Gas and Steam Engines Installation of Plant Foundation, How to Build, Ingredients Correct Location of Engine and Dynamo Belts Balance-wheel on Armature Shaft Power Required for Incandescent and Arc Lamps Losses of Power by Belt and Otherwise Regu- lation of Engine Required for Electric Lighting Direct-connected Plants, Advantages of Same Variations in Incandescent Lights, Causes, How to Remedy Silencing Air-suction, .. .. .. 111-122 CHAPTER VI. OIL ENGINES CONNECTED TO AIR-COMPRESSORS, WATER-PUMPS, ETC. Direct-connected and Geared Air-compressing Outfits, with Dimensions and Pressures Obtained Calcu- lations of Horse-power Required Tables of Pres- sures and Other Data Efficiencies at Different Altitudes Pumping Outfits Described in Detail, with Dimensions How to Calculate Horse-power Required Oil Engines ^Driving Ice and Refrig- erating Machines, Calculations of Power Required Friction-clutches, . . 123-138 Vlll CONTENTS. CHAPTER VII. INSTRUCTIONS FOR RUNNING OIL ENGINES. PAGE General Instructions and Remarks Cylinder Lubri- cating Oil Instructions in Detail as to Running Hornsby-Akroyd Type, the Crossley Type, the Campbell Type, and the Priestman Type of Oil Engine General -Remarks Regulation of Speed How to Reverse Direction of Running of En- gine, with Diagrams of Valve Settings, . . . . 139-156 CHAPTER VIII. REPAIRS. Drawing Piston Taking Off Piston-ring Grinding in of Valves Adjustment of Crank-shaft and Connecting-rod Bearings How to Fit New Piston-ring to Cylinder Fitting New Skew and Spur Gear Renewing Governor Parts, . . . . 157-160 CHAPTER IX. VARIOUS ENGINES DESCRIBED. General Description, with Illustrations of Different American and English Oil Engines Method of Working Sectional Cuts The Crossley The Cundall The Campbell The Priestman The Mietz and Weiss The Hornsby-Akroyd The Diesel Portable Oil Engines Described and Illustrated, 161-183 TABLES. PAGE I. Sizes of Crank-shafts, 27 II. Various Air Pressures, 126-127 III. Efficiencies of Air Compressors at Different Altitudes, . . 129 IV. Mean Pressure of Diagram of Gas (Ammonia) Compressor, 135 ' J Tests of Various Oil Engines Made in Edin- VL ( burgh, 184-185 VII. Calorific Power of Various Descriptions of Petroleum, etc., 186 VIII. Composition, Physical Properties, etc., of Vari- ous Descriptions of Petroleum, . . . . 187 IX. Oil Fuel, .. .. 188 X. Calorific Power of Crude Petroleum, . . . . 188 Index, 189-196 LIST OF ILLUSTRATIONS. XI LIST OF ILLUSTRATIONS. PAGE Abel Oil-tester, 91 American-Thompson Indicator, . . . . . . . . 65 Apparatus for Open Fire Test, 91 Automatic Air Inlet- Valve, .. .. .. .. ..'41 Beau de Rochas Cycle, Diagram, 16 Campbell Diagrams, . . . . . . . . . . . . 167 Campbell Sprayer, .. .. .. 5 Campbell Type Engine, . . . . . . . . . . . . 166 Cams, Air and Exhaust, . . . . . . . . . . . . 37 Connecting-rod, 31 Connecting-rod Bearings, . . . . . . . . . . 159 Connecting-rod, Phosphor-bronze, . . . . . . . . 32 Crank-shaft Bearing, 54 Crank-shafts, Balanced, 28 Crank-shafts, Slab Type, *. . . 26 Crosby Indicator, 68 Crossley Diagrams, 163 Crossley Sprayer, 4 Crossley Type Engine, 162 Cundall Type Engine, . . . . 164 Cylinder, . . . . . . . . . . ... . . . . 22 Cylinder, 24 Diagram of Valve-settings, . . 60 Diagrams, Reversing Engine and Cams, . . . . . . 155 Diesel Motor, 178 Diesel Motor, Indicator Diagram, . . . . . . . . 180 Xll LIST OF ILLUSTRATIONS. PAGE Direct-connected Air-compressing Plant, 124 Dynamo Fly-wheel, 116 Electric Spark Igniter, 6 Engine and Dynamo, Belt-driven, .. .. .. ..112 Engine and Refrigerating Machine, 132 Engine Connected to Water-pump, 130 Engine Connected to Water-pump, Small Type, . . . . 131 Engine foundation, .. .. .. .. .. ..114 Exhaust Silencing Pit, 101 Exhaust Washing Device, . . . . . . . . . . 102 Fly-wheel, 36 Friction-clutch, 138 Geared Air-Compressing Plant, 128 Governor, Centrifugal Type, . . . . . . . . 45 Governor, Hit-and-miss Type, 47 Hill Self-recording Speed Counter, 85 Heating Lamp, 142 Heating Water-pipe Arrangement, . . . . . . . . 108 Heating Water-pipe Arrangement, * . . 109 Hornsby-Akroyd Engine and Dynamo, Direct-connected, 118 Hornsby-Akroyd Horizontal Type, 174 Hornsby-Akroyd Sprayer, . . . . . . . . 10 Hornsby-Akroyd Vaporizer, 3 Hornsby-Akroyd Vertical Type, . . . . . . . . 175 Indicator Cock, 66 Indicator Diagram, . . . . . . . . . . 76 Indicator Diagram, . . . . 77 Indicator Diagram, 79 Indicator Diagram, 80 Indicator Diagram, . . . . . . . . . . . . 82 Indicator Diagram, Light Spring, . . . . . . . . 89 Indicator Diagram, Varying Pressures, . . . . . . 46 Indicator Diagrams, Hornsby-Akroyd, 176 Indicator, Reducing Motion, . . . . . . . . . . 67 Mietz and Weiss, Indicator Diagram, 172 Mietz and Weiss Engine and Dynamo, Direct-connected, 120 LIST OF ILLUSTRATIONS. Xlll PAGE Mietz and Weiss Type Engine, . . I7 1 Oil Engine with Testing Apparatus Applied, . . . . 62 Oil-filter, ...... "49 Oil-pump, . . . . . . . . J 44 Oil-supply Pipe, . . . . . . . . . . 48 Piston-ring, 35 Piston, Section of, . . . . ' 34 Piston with Piston-rings, . . . . 56 Planimeters, 72 Planimeters in Position, . . . . . . 74 Portable Oil Engine, 182 Priestman Engine, 169 Priestman Indicator Diagrams, 170 Priestman Sprayer, . . 14 Priestman Vaporizer, 13 Self-starter, 106 Silencing Device, . . . . . . . . . . . . . . 104 Spur-gearing, 44 Starting Cam, 143 Tachometer, . . . . . . . . . . . . . . 84 Tachometer, portable, 85 Testing Oil-pump, 147 Two-cycle Plan, 17 Two-cylinder Engine, 52 Valve-box, 39 Valve-closing Springs, 40 Valve-levers, 146 Valve Mechanism, ' . . . . 44 Valves, Air and Exhaust, 42 Viscosometer, . . . . . . . . . . . . . . 94 Water-circulating Pump, 98 Water-cooling Tank and Connections, 97 Worm Gear, 43 CHAPTER I. INTRODUCTORY. THE internal combustion engines which are treated of in this work are those using heavy kerosene as fuel, otherwise called petroleum, coal oil or Scotch paraffin, and similar oils having specific gravity varying from .78 to .85 with flashing point of 75 to 300 Fahr. The use of heavy oil for producing power in internal combustion engines appears to have received the at- tention of inventors as early as 1790, though no satis- factory practical kerosene or petroleum engine is re- corded as having been made until about thirty years ago. Those engines using the lighter grade fuels, such as benzine, or gasoline, or naphtha, were commonly used previous to the invention of the kerosene-oil engine. The problem of efficiently producing a vapor and suitable explosive mixture of air with such vapor from these light oils was comparatively a very simple matter. Such engines are gas engines proper, with simply some form of carburetter added, but they can use only gasoline or naphtha as fuel. These are not treated of in this book, only oil engines proper being 2 OIL ENGINES. described and discussed. The term oil engine refers to an internal combustion engine so designed as to effec- tively deal with and convert into power crude petro- leum just as it is pumped from the earth, or any of the other fuels already named, without the aid of any out- side agency or separate apparatus. The production of a satisfactory device for properly vaporizing the heavier oils at first offered a problem which it was thought difficult to solve, and remained so for many years before the efficient vaporizing kero- sene engines now in use were constructed. IGNITERS. The first oil engines built had their charge of vaporized oil and air ignited by means of the flame igniter, which has, however, now entirely given place to the four following means of ignition : (a) Hot surface ignition, aided by compression. (b) Hot tube. (c) Electric igniter. (d) High compression only. The first-named type of igniter is illustrated in Fig. i. In this instance the heated walls of the vaporizer act as the igniter, aided by the heat generated during com- pression of the gases. The chamber being first heated, afterward the proper temperature is maintained by the heat caused by the internal combustion of the gases. The best-known vaporizer and igniter of this type is that in the Hornsby-Akroyd Oil Engine. Various other somewhat similar devices in which sufficient heat is maintained to cause ignition automatically are also now being made. The second type, that of the hot tube, is shown in INTRODUCTORY. 3 Fig. 2 and Fig. 3. This igniter consists of a porcelain, nickel or wronght-iron tube, which is maintained at red heat by external heating lamp, and is placed in the end INTRODUCTORY. of the combustion chamber space, being always open to the cylinder, as shown. THE ELECTRICAL IGNITER is made in various forms; AIR INLET TO CYLINDER OIL SUPPLY FIG. 3. that illustrated in Fig. 4 is of the " jump-spark" type. The current from-the battery or other source of energy is connected to the regular induction or Rhumkorff coil O OIL ENGINES. in which there are two windings of wire wound on core of iron wire, the one being made of coarse wire, the other winding being of fine wire. Where a vibrator is used in connection with the coil, the cam-shaft is arranged to close a switch, thus causing a series of sparks to jump across from one terminal' to the other in the cylinder and ignite the gases. Other forms of FIG. 4. electrical igniters are the New Standard and the Splitdorf jump-spark apparatus. The fourth-named type of ignition, that due to com- pression in the cylinder alone, is found only with the Diesel motor. The combustion is one of its unique features. In this type of engine the compression pres- sure inside the cylinder reaches about 520 pounds per square inch, the compression being arranged to con- tinue until combustion commences to take place. Advantages are claimed for each of these igniting devices by the various manufacturers using them. The INTRODUCTORY. 7 electrical igniter is easily controlled and is reliable, but the batteries, in unskilled hands, sometimes give trouble, and it is essential that the parts forming the contacts be kept clean and in good condition ; otherwise faulty working of the engine will result. The tube igniter always requires heating by the ex- ternal heating lamp, upon which it is dependent, like all types of vaporizers which require external heat ; so likewise is also the tube dependent entirely upon it. The former difficulty with ignition tubes and their frequent bursting has now been minimized by the use of nickel alloy, porcelain or other material more suit- able than wrought iron for this purpose. The hot surface type of igniter formerly gave trouble caused by its temperature cooling down at light loads. This type, however, which has now been adopted in various forms, has been designed to overcome this dif- ficulty, and can now be relied upon to keep hot when running at light loads. VAPORIZERS. As already stated, the problem of efficiently vaporizing petroleum was the most difficult feature to encounter in designing oil engines. This obstacle has been, however, entirely overcome by different methods, and of recent years many types of engines using kerosene as fuel have been designed, and are now working satisfactorily. The different types of vaporizers have been classified as follows: I. The vaporizer into which the charge of oil is injected by a spraying nozzle. being connected to cylin- der through a valve. 8 OIL ENGINES. 2. That into which the oil is injected, together with some air, the larger volume of air, however, entering the cylinder through separate valve. 3. That vaporizer in which the oil and all the air supply (passing over it) is injected, but being without spraying device. 4. The type into which oil is injected directly, air being drawn into the cylinder by means of a separate valve, the explosive mixture being formed only with compression. With each type of vaporizer some advantage is claimed, but corresponding disadvantage can perhaps be named. For instance, in type I, though the mixture of oil and air is more complete, and the vaporizing probably greater than in the other types, yet the system of having an explosive mixture at any other place than in the cylinder and at any other period than at the time of actual ignition may be urged as a great dis- advantage to this system. With class 4 the mixture of air and oil may not be so complete, and the initial pressure in the cylinder consequent upon explosion less than the pressure ob- tained with other types; yet the extreme simplicity of this type is an advantage in daily use which cannot be overestimated. With class 2 the highest mean effective pressure is obtained and the lowest consumption of oil per H. P. is believed to be recorded, but this type generally re- quires a heating lamp to maintain the proper tempera- ture, and then on the efficiency of the heating lamp depends the efficiency of the engine itself. There have, INTRODUCTORY. 9 in recent, years, been perfected some very simple smokeless kerosene burning lamps, and this previous difficulty has now accordingly been overcome. One of the chief difficulties in designing a satisfac- tory vaporizer is that of making it such that at all loads and under all conditions it will vaporize the fuel. The heat of the chamber should be high enough to vaporize the oil, but never hot enough to decompose the oil, or a deposit of carbon will be made which is injurious to the satisfactory working of the vaporizer. It would, therefore, appear that each type, while possessing features giving it individually an advantage as compared with other types, has some detracting feature also. The following is a description of the various types of vaporizers, showing the four different methods named in detail : THE HORNSBY-AKROYD vaporizer is shown at Fig. I, and also as it is at present manufactured in Fig. 76, which illustrates a complete section of this engine. The oil in this method of vaporizing is injected through the spray nipple, as shown in Fig. 5, directly into the vaporizer by the oil-supply pump. The injec- tion of oil into the vaporizer takes place only during the air-suction stroke. The lever which actuates the air-valve also simultaneously operates the oil-pump. When the piston is at the outward end of the cylinder, the suction period being then completed, the cylinder is filled with atmospheric air, and the vaporizing chamber, which is at all times open to the cylinder, is also at the same time filled with oil vapor. The compression stroke of the piston then com- 10 OIL ENGINES. mences; the atmospheric air in the cylinder is thus driven through the contracted opening between the cylinder and the vaporizer into the vaporizer itself, already rilled with the oil vapor. As compression due to the piston movement proceeds, the mixture which FIG. 5. at first is too rich to explode in the vaporizer gradually becomes more diluted with the air, and when the com- pression stroke is completed the mixture of oil, vapor and air attains proper explosive proportions. The mixture is then ignited simply by the hot walls of this INTRODUCTORY. II same vaporizing chamber and also by the heat gener- ated by compression. No other means of ignition is necessary. No heating lamp is required to maintain the necessary temperature of this vaporizer; a lamp is, however, required to heat it for a few minutes before starting. THE CROSSLEY method of vaporizing. This vapor- izer is shown in section in Fig. 2. It consists of three main parts, the body, the passages,- and the chimney cover. There are no valves about the vaporizer itself ; it is arranged to keep hot, and while not in contact with the cooled cylinder is near to the vapor inlet valve to which it delivers its charges. The passages inside which vaporization of the oil takes place are detach- able. The wrought-iron ignition tube is placed below the vaporizer communicating directly with the cylinder. A heating lamp is always required to heat the vaporizer and maintain the ignition tube at proper red heat. The method of vaporizing is as follows : When the suction stroke of the piston commences the oil inlet valve is automatically lifted from its seat and allows oil to be drawn into the vaporizer through it. The vaporizer blocks having been heated by the inde- pendent lamp, and likewise the chimney being hot also, heated air is drawn in passing first through the aper- tures in the sides of the chimney communicating with the passages of vaporizer blocks. The air is thus thor- oughly heated, and next it passes over the heated cast- iron blocks. To these blocks the oil also flows from the oil measurer. The heated air here mingles with 12 OIL ENGINES. the oil and vaporizes it, and the two together properly mixed are drawn into the cylinder through the vapor valve. Simultaneously, while the above process of vaporization is proceeding, air is also entering the cylinder through the air-inlet valve on the top of the cylinder. Thus, when the suction stroke of the piston is completed the cylinder is full of heated oil vapor drawn in through the vapor valve, too rich to explode by itself, and also atmospheric air drawn in through the air valve. Both elements are then compressed by the inward stroke of the piston completing the mixture of the oil, vapor and air. When compression is com- pleted, ignition takes place by the gases coming in con- tact with the red-hot ignition tube. THE CAMPBELL. This method of vaporizing differs from those already described in that the whole charge of air to the cylinder is drawn in through the vaporizer. No air whatever enters the cylinder otherwise. Fig. 3 represents the Campbell vaporizer in section. The fuel oil is fed to the vaporizer by gravitation from the fuel tank placed above the engine-cylinder, and enters the vaporizer with the incoming air. At the be- ginning of the suction stroke the automatic air-inlet valve is opened by the partial vacuum in the cylinder, and the oil which has entered through the small holes at the inlet valve is drawn through the heated vaporizer into the cylinder. At the compression stroke the mix- ture of the vapor is completed, and being forced into the ignition tube is ignited in the ordinary way. The ignition tube is heated by heating lamp fed by gravita- tion from the oil tank. The same lamp also heats the INTRODUCTORY. 13 vaporizer as well as the tube. The governing is effected by allowing the exhaust-valve to remain open when the normal speed is exceeded ; consequently no charge is in that case drawn into the cylinder. The method of vaporizing the oil with the PRIEST- MAN engine is as follows : FIG. 6. The oil is stored under pressure in the fuel-tank, which pressure is created by the separate air-pump actuated from the cam-shaft. The oil is thus forced to the sprayer, which device is shown in Fig. 7, where it meets a further supply of air. The mixing of the air and oil takes place just as both elements are injected OIL ENGINES. into the vaporizing chamber, as shown in Fig. 6. The heating of the vaporizer is first accomplished with sep- arate lamp ; afterward, when the engine is working, the exhaust gases heat the vaporizer by being carried around in the outside passage of the vaporizer cham- A o ) " On. TMX Caxec ^ ' On. PASSAGF . FIG. 7. ber, as shown in Fig. 6. On the outward or suction stroke of the piston the mixture of oil vapor and air already formed and heated in the vaporizer is drawn into the cylinder through the automatic inlet-valve shown on the left of Fig. 6. The compression stroke INTRODUCTORY. 1 5 then takes place in the ordinary course of the Beau de Rochas cycle. The governing is effected by means of the pendu- lum or centrifugal governor, shown at Fig. 7, control- ling the amount of air entering the vaporizer as well as reducing the supply of oil simultaneously. Thus, the explosive mixture is always composed of the same proportions of air and oil, but as the supply of air is thus curtailed the compression in the cylinder is also necessarily reduced when the engine is working at half or light load. The governor thus varies the pressure of the explosion, reducing it when necessary, but not causing at any time the complete omission of an ex- plosion. , The system of throttling the pressure, somewhat similar to a steam engine, produces very steady run- ning. By this system a thorough vaporization of the oil takes place. The ignition of the gases is caused by electric spark- igniter, the spark being . timed by contact-pieces ac- tuated from the cam-shaft and horizontal rod actuating the exhaust-valve, and is of the " jump-spark" type as shown in Fig. 4. The oil engines now in use and herein described are designed with their valve mechanisms arranged to work either on the Beau de Rochas cycle, or on the two-cycle system. These two cycles are variously des- ignated, the former being generally known as the Otto cycle, the four-cycle, and sometimes, but erroneously, the two-cycle. Correctly, it should be named the Beau i6 OIL ENGINES. de Rochas cycle after its inventor. The other cycle is generally known as the " two-cycle/' or sometimes as the " single cycle," the first designation, however, being correct. With those engines working on the Beau de Rochas cycle, which includes now many if not all the leading and best known types of engine, THE BEAU DE ROCHAS CYCLE. the cycle of operation of the valves is as follows : (a) Drawing in the air and fuel during the first outward stroke of the piston at atmospheric pressure. (b) Compression of the mixture during the first re- turn stroke of the piston. (c) Ignition of the charge and expansion in the cylinder during second outward stroke of the piston. (d) Exhausting, the products of combustion being expelled during the second return stroke of the piston. These operations are clearly shown in the accom- panying illustration, and thus, in this system, the one cycle is completed in two revolutions of the crank- INTRODUCTORY. shaft or during four strokes of the piston. The im- pulse at the piston is obtained only once during the two revolutions. The second system, named "two-cycle," is com- THE TWO-CYCLE PLAN. pleted in one revolution, or every two strokes of the piston, and is also clearly shown by the accompanying illustration. The operation of the valves is as follows : l8 OIL ENGINES. (a) During the first part of the outward stroke of the piston that is, until the piston uncovers the ex- haust-port expansion is taking place. When the ex- haust-port is opened the products of combustion are expelled ; the piston then moves a little farther forward and uncovers the air-inlet port communicating with the crank chamber. The air at slight pressure at once rushes into the cylinder, assisting the expulsion of the burnt gases, and filling the cylinder with air already compressed to five or six pounds in the crank chamber ; this completes the first stroke of this cycle. (b) The next stroke (being the inward stroke of the piston) the supply of incoming air and fuel is first taken in; then compression of the charge takes place. Ignition follows when the piston reaches the back end. These two strokes of the piston, or one revolution of the crank-shaft, completes this cycle of operation. ADVANTAGES AND DISADVANTAGES OF BOTH CYCLES. The Beau de Rochas cycle engine, having only one impulse during two revolutions, requires the dimen- sion of the cylinder to be greater in order to obtain a given power than would be required with the two- cycle system. Large and heavy fly-wheels must also be fitted to the engine in order to maintain an even speed of the crank-shaft. On the other hand, this cycle has many advantages. The explosion is con- trolled more readily. The idle stroke of the inlet air cools the cylinder and allows sufficient time to entirely expel the products of combustion, and with this sys- INTRODUCTORY. IQ tern no outside air-pump is required, nor is there any fear of the compression being irregular by leakage in the crank chamber or otherwise. With the two-cycle system air must in some way be independently compressed. If this is accomplished in the crank chamber, then leakage may occur and bad combustion follow, with accompanying bad results to valves and piston. More cooling water is also needed to cool the cylinder, and the proper lubrication of the piston may consequently be very difficult to accom- plish. With this system steadier running is obtained, nor are the heavy fly-wheels required as with the engines of the Beau de Rochas cycle. Explosive engines were formerly quite extensively built to work on the two-cycle plan, either with inde- pendent air-pump or by compressing the air in the crank chamber, but as soon as the Otto patent expired a large nunlber of engines were changed to that sys- tem. The former two-cycle engines were not economi- cal, and when the economy of the Beau de Rochas or Otto cycle was demonstrated its superiority was quickly acknowledged. Oil engines have more generally been built of the four-cycle than other explosive engines. In this work only one is described, which is operated on the. two- cycle system, for which very satisfactory results are claimed. CHAPTER II. ON DESIGNING OIL ENGINES. THE term " oil engine," as already stated in Chap- ter L, refers here only to those engines using as fuel ordinary kerosene or the crude and inferior heavy grades of petroleum of specific gravity .79 to .85, the power developed being derived from the explosion and combustion of a mixture of hydrocarbon gas and air similar to the impulse obtained in other internal com- bustion engines. Oil engines are similar in principle to gas engines, but as the liquid fuel must be vaporized or gasefied in an oil engine, an additional apparatus, as already fully described in the last chapter, is neces- sary to perform this process, which, with a gas engine, is accomplished separately and previously in the gas works or by " producer" gas plant. The formulae used for designing gas engines are generally applicable to oil engines also, but a greater factor of safety is sometimes allowed with the oil engine because it is possible, especially with some types of vaporizers, to occasionally have greater pressure of explosion than is ordinarily created chiefly by reason of improper combustion of the previous charge or by the governor having cut out several charges. For this ON DESIGNING OIL ENGINES. 21 possible increased pressure, the strength of parts otherwise sufficient if of smaller dimensions are conse- quently increased. The formulae herein given are derived chiefly from experience, and are believed to be in accordance with the best modern practice, and are also taken from well-known gas-engine hand-books by kind permission of the authors. EXPLOSIVE ENGINES are of substantial design in or- der to withstand the continual shock and vibrations incident thereto, and should pre-eminently be as acces- sible as possible in the working parts, which mdy require adjustment from time to time when in actual service. The starting gear and other parts to be handled by the attendant when starting and running the engines incident to their operation should be placed in close proximity to each other. Simplicity in construction is, in the writer's opinion, the essential feature of an oil engine. Above all other prime movers, the oil engine is a machine intended for use in any part of the world where its fuel is obtain- able, and where, perhaps, no mechanic is available. Accordingly, all the valves should be arranged so as to be easily removed for examination and repairs. The spraying and igniting device, as well as the vapor- izer, should be so designed as to facilitate removal and repairs. In short, an oil engine, to be successful mechanically and commercially, should be so con- structed that it can be successfully worked, cleaned and adjusted by entirely unskilled attendants. The mean effective pressure evolved in the different types of oil engines now in use varies from 40 to 75 22 OIL ENGINES. Ibs., and is less than the pressure obtained in the cylinder of gas and gasoline engines, which is often as high as 90 Ibs. Consequently, to obtain relatively the same power, the dimensions of the oil-engine cylin- der will be greater than those of the gas engine. THE CYLINDER is made in different types, either to bolt up to the bed-plate as shown in Fig. 8, or is made FIG. 8. with faced flanges on the sides to be bolted down to the engine bed-plate, as shown in Fig. 9, in both in- stances being cast all in one piece. The cylinder as manufactured by some European makers is made in two and sometimes three parts, with internal joint. The inner liner being held at the back end only, the front end joint between the liner and the outer cylinder is made with rubber ring. This arrangement leaves the inner sleeve free to expand lengthwise, and ON DESIGNING OIL ENGINES. 23 also allows the strain of the explosion to be transmitted only through the outer cylinder. Except for the larger- sized engines of over 40 H. P., the cylinder made in one piece is very satisfactory. The circulating water space around the cylinder is made as is shown in Figs. 8 and 9, being f " to ij" deep, the water inlet and outer pipes being so arranged as to allow free and efficient circulation of the cooling water around the cylinder. By some manufacturers this space for water is arranged to cool only that part of the cylinder cover- ing the travel of the piston-rings, instead of the whole cylinder, as here shown. Other cylinders are cast in one piece with the frame or bed-plate having internal sleeve. This arrangement has, among other advan- tages, that of cheapness, but it has the disadvantage that if the cylinder for any reason should require re- newing the whole frame must be renewed with it. The cylinder cover is made in some engines with the valves, air-inlet valve housing or guide inserted into it, and with space also in the larger-sized engines ar- ranged for cooling water-jacket. Other engines have the igniter placed in the cover, while cylinders of the type shown in Fig. 8 require no cover, the vaporizer flange closing the contracted hole in the end of the cylinder. The cylinder in all cases should have the valves brought as close as possible to the cylinder walls, and all ports or passages so arranged as to offer the mini- mum amount of internal cooling surface to the hot gases of combustion. CYLINDER CLEARANCE. The percentage of clear- ON DESIGNING OIL ENGINES. 25 ance in the cylinder is ascertained by dividing the total clearance in the cylinder, including all ports or other spaces, by the piston displacement. The clearance allowed will depend upon the pressure of compression as determined by experiment and by the indicator diagram, producing properly timed ignition and combustion. This pressure, it will be noted, on referring to the va- rious indicator cards shown herein, now varies in differ- ent types of engines from 50 to 70 pounds, which it is believed is representative of present practice, with the exception of the Diesel motor, which engine com- presses to over 500 pounds before combustion takes place in the cylinder. This exceedingly high compres- sion is rendered possible by the special Diesel system of injection of the charge of fuel. The fuel in this case enters the cylinder only at the extreme end of the stroke of the piston, the compres- sion period being then completed. THE CRANK-SHAFT of an oil engine must be made of sufficient strength not only to withstand the sudden pressure due to ordinary explosion, but also to with- stand the strain consequent upon the greater explosive pressure which may possibly be caused by previous missed explosions, as already described. The crank- shaft is proportioned in relation to the area of the cylinder and the maximum pressure of explosion and the length of stroke. Oil-engine crank-shafts are usually made of the " slab type," as shown in Fig. 10. It has been said with regard to explosive engines that their comparative efficiency may be to a certain extent 26 OIL ENGINES. gauged by the strength of the crank-shaft, because if the crank-shaft is of too small dimensions, it will spring with each explosion, causing the fly-wheels to run out of truth and also uneven wear of the bearings. Table I. gives a list of dimensions of crank-shafts of both oil and gas engines which are made by some leading manufacturers, together with the dimensions of the cylinder and stroke. Different formulae for the dimensions of crank- FIG. 10. shafts are given by various writers on this subject. The following, for example (which is recommended by the writer), is given by Mr. William Norris. 120 5" = load on piston (area of cylinder in inches X maximum pressure of explosion. / = length of stroke in feet. D = diameter of crank-shaft in inches. ON DESIGNING OIL ENGINES. This formula, however, neglects the bending action due to the distance of the centre of crank-pin from the centre of the bearings. The diameter should be thus slightly increased. Mr. Norris also gives a lengthy description, with example, of ascertaining all the dimensions of the crank-shaft by means of the graphic method. TABLE I. SIZES OF CRA':K-SHAFTS. Cylinder. A. B. C. D. E. F. G. DUim. Stroke. in. in. in. i . in. ft in in. 5 8 If l| 4 4 2 6i 2i 5t 9 2i 3 4* a* 2f 81 3i 71 II *f 3i 5* 4 3 9i 4l 8J 15 3i 4 7^ 2j 3* i2| 5 8^ 18 3i 4 9 3 3i I 2 5 9* 18 3* 4j 9 3t 3i i 3 5i 12 18 4i 4f 9 3i 4* i 3* 6i * 21 4i 4t 10} 4 3* i 3f 4 14 21 5^ 5* TO* 4i 4l 1 5 8* 17 2 4 7 8 12 5f - 7i I IO.-J- 10 19 30 7* 8 13 6 9 2 2 1 1 7 I 2 'TV 2f 6 2yV *l 8f 3l 9 14 2 V 3 7 2l 3ft 4 1 1 15 3rs" 4 7^ A 44 I4 4t '3i 16 3B 4J 8 3yV 4l i3f 5l THE BALANCING of crank-shafts and reciprocating parts is another important feature of an oil engine. With a single-cylinder explosive engine to perfectly accomplish the balancing is impracticable. Most manu- facturers, therefore, only balance their engines as far ?C^B ON DESIGNING OIL ENGINES. 2Q as the horizontal movement is concerned. The follow- ing formulae is considered correct, and has proved satisfactory for the horizontal type of engines : w = weight in Ibs. of balance weight. C crank-pin and rotating part of connecting-rod in Ibs. R =. radius of crank circle in inches. G = two-thirds weight of all remaining reciprocat- ing parts in Ibs. 5* = weight of crank-arms in Ibs. r = distance of centre of gravity of crank-arms from centre of rotation. a = distance of centre of gravity of counterweight from centre of rotation. Some designers, however, the writer has observed, make the crank balance weights as large as space be- tween bearings and engine bed will allow that is, when the weights are fastened to the crank-arms, as shown in Fig. n, thus overbalancing the crank and reciprocating parts. While this would appear bad practice, such engines have been known to run without the slightest vibration. For the vertical type of engines the whole weight of the reciprocating parts, instead of two-thirds weight, has been satisfactorily taken. Crank-shafts of explosive engines are sometimes bal- anced by metal suitably placed-on the rim or hub of the fly-wheel ; otherwise some wheels are made with recess 3O OIL ENGINES. left in rim placed just in line with crank-pin, so that the metal left out of the rim of the fly-wheel will equalize the metal which is contained in the crank-pin and other parts to be balanced. Balancing by means of the recess at the outer radius of the fly-wheel has the advantage of requiring no extra metal, and is cheaper as regards workmanship as compared with the system as shown in Fig. n. In each of these methods, how- ever, the fly-wheel itself is out of balance, and when revolving tends to make the crank-shaft run out of truth. The more expensive method of placing balance \veights on the cheek of the crank-shaft itself, as shown in Fig. n, is considered by the writer the most satis- factory method. In this way the crank-pin and recip- rocating parts are themselves separately balanced re- gardless of the fly-wheels, and the fly-wheel being itself also balanced, when running allows the crank-shaft to remain absolutely true. Further, it is also advan- tageous to core small recesses in the fly-wheel rim, to be filled up, if required, with lead so as to exactly bal- ance the wheel should it, from inequality in casting, be heavier in one part than in another. This, how- ever, is only requisite in special cases, or where the engine is running at a very high rate of speed. CONNECTING-RODS are made of various designs in cross-section, but that chiefly used is made of soft steel and circular, with marine type brasses at crank-pin end and similar bearings at the piston or small end. By some makers the latter bearing is made with adjust- able wedge and screw, the end of the connecting-rod ON DESIGNING OIL ENGINES. then being slotted out, with brass bushes fitted into it, as shown at Fig. 12. For small engines a good and cheap form of connecting-rod is made .of phosphor- bronze metal, as shown in Fig. 13. FIG. 12. The connecting-rod of a single-acting engine has, chiefly, compression strains to withstand; both the outer end bearings have little or no strain on them, except that due to momentum of the reciprocating parts. The connecting-rod should be from two to OIL ENGINES. three strokes in length. In computing its strength, the connecting-rod can be taken as a strut supported FIG. 13. at either end. The mean diameter when made of mild ON DESIGNING OIL ENGINES. 33 steel is arrived at by the following formulae, as given by authorities on steam-engine design :- x == 0.035 VD I Vm. x = mean diameter of connecting-rod (half sum of diameter of both ends). D = diameter of cylinder in inches. / distance in inches between centre of connecting- rod. m = maximum explosive pressure in Ibs. per square inch. This formula, however, is excessive for medium and slow speed engines, and in such instances the writer has used the following formulae with satisfac- tory results namely: 0.028 D I Vm. THE PISTON in single-acting engines is generally of the trunk pattern, as shown in Fig. 14, with internal gudgeon-pin placed in the centre of the piston, secured at either end to the piston by set-screws. The steam- engine cross-head and slide-bars are dispensed with, the power being transmitted directly from the gudgeon- pin of the piston to the crank. The piston is made of hard close-grained iron, and should not be less than 5-16" in thickness for small engines and slightly heavier for the larger sizes. In 34 OIL ENGINES. each case the metal is thicker at the back, than at the front end. The piston is usually 1.6 diameters in length. Three cast-iron piston-rings, as shown in Fig. 15, are fitted to the smaller engines, four and five rings being required to keep the piston tight in the larger sizes. A single ring is sometimes added, placed in front of the gudgeon-pin, but its use is not recom- mended. The pressure on the piston, caused by the FIG. 14. explosive pressure and due to the angularity of the connecting-rod, should not be greater than 25 Ibs. per square inch of rubbing surface. PISTON SPEED. The speed of the piston for hori- zontal oil engines is usually allowed to be not greater than 600 feet per minute; for the vertical type this is somewhat increased. The movement of the valves, oil spraying and vaporizing devices, it is usually assumed, precludes a higher speed. The writer has, however, worked a ij B. H. P. vertical oil engine running at ON DESIGNING OIL ENGINES. 35 600 revolutions per minute with satisfactory results. Thus, 300 movements of the valves, o ; l-pump and sprayer were completed per minute. FLY-WHEELS on explosive engines are made much heavier than in steam engines of the same capacity. FIG. 15. The power is generated during only about twenty-five per cent, of the time of working in single-cylinder four-cycle explosive engines, hence the necessity of the very heavy fly-wheels in order to maintain a steady speed of the crank-shaft. The function of the fly- 30 OIL ENGINES. wheel, it may be said, is to store up the energy im- parted during the explosion period and pay it out again during the period of the three idle strokes of compres- sion, suction and exhaust. Two fly-wheels are gener- ally supplied, one placed on each side of the main bearings. Some of the European makers, however, FIG. 16. are now building their larger engines provided with one heavy fly-wheel only, a separate outside bearing being fitted in that case. The diameter of the fly-wheel is usually such that the peripheral speed is from 4000 to 5000 ft. per minute ; 6000 ft. is considered the maximum allowable speed. ON DESIGNING OIL ENGINES. 37 The hub of the fly-wheel is sometimes split and bolted together. Oil-engine fly-wheels are usually made as shown in Fig. 16. The weight of the rim can lated as follows : C X I. H. P. w ~ D 2 v N S * where C constant. I.H.P. = indicated horse-power. D = diameter of fly-wheel in feet. N = revolutions per minute. w = weight in Ibs. of rim. FIG. 17. The constant varies according to the fluctuation in speed permissible ; for engines required to run dy- namos for electric lighting purposes, C'= 50,846,290,- ooo. For engines actuating general machinery C is considered sufficient when taken as 30,507,700,000. The cams are made of cast iron or steel and are usually designed as shown in Fig. 17. Cast iron is ad- 38 OIL ENGINES. vantageously " chilled" so as to withstand the wear of the rollers. The cams, it is considered, however, should preferably be designed of larger diameter than they are now made. The air cam is usually made about f " wide. The exhaust cam, which has more work to perform at the period of opening the valve, is made with wider sur- face than the air cam. CYLINDER LUBRICATORS. The lubrication of the pis- ton in explosive engines is of great importance. On those engines where it is convenient to use it, a mechanical type of lubricator is added. This device consists of an oil reservoir into which a wire attached to a revolving spindle is periodically dipped, the wire being also arranged to wipe over a projection which conducts the oil to a receptacle placed above the reser- voir and connected to the top of the cylinder. The re- volving spindle is driven by belt from the cam-shaft. This lubricator is advantageous because the oil must be always fed to the piston while the engine is working, and the lubricator cannot be left unopened by the at- tendant, and also because all grit or dirt in the oil is precipitated to the bottom of the reservoir and cannot flow to the piston. Sight-feed lubricators are also now used for the lubrication of the piston, and have proved quite as satisfactory as the mechanical oiler. VALVES AND VALVE-BOXES. The dimensions of the air-inlet and exhaust valves are governed by the diam- eter of the cylinder and the piston speed. The style of the valve-box recommended is that made separate and bolted to the cylinder. The valve-box can then ON DESIGNING OIL ENGINES. 39 be entirely renewed if necessary and at small expense. This type of valve-box is shown at Fig. 18, both valves being operated from the cam-shaft. The springs neces- sary to close air and exhaust valves in engines over 10 brake or actual H. P. are best placed so as not to be in close proximity to the heat. An arrangement of the closing springs of this description, with a type of spring having separate hooks at each end, is shown in Fig. 19. Where the air-inlet valve is made automatic, it is FIG. 18. opened by the partial vacuum in the cylinder during the suction period, and closed by a delicate spring, as shown in Fig. 20. The air and exhaust valves and port openings are usually made of such an area that the velocity of the air inlet as it enters the cylinder is 100 feet per second the velocity of the exhaust gases through the exhaust or outlet being about 80 feet per second, presuming the exhaust products to be expelled at atmospheric pressure. The air-inlet valve, if auto- matic, should be so arranged as to allow ingress of air' 4 OIL ENGINES. without choking. In calculating the area of valve ports or passages, allowance must be made for valve VALVE BOX } UJ ( FIG. 19. guide or other obstruction in the passages. The ve- locity of the air is found in the following formulse : ON DESIGNING OIL ENGINES. 4! V = velocity of air in ft. per second. P = piston speed in ft. per second. a -=. area of piston in inches. a x = area of valve opening in inches. THE EXHAUST BENDS close to valve-box should when possible be of not less than 5" radius for the FIG. 20. smaller engines, which dimension should be increased for larger-sized engines. The valves are made of forged steel, either in one piece 'or with cast-iron valve and wrought-iron or steel stem fitted into it, and are shown in Fig. 21. Some manufacturers prefer the latter on account of cheap- ness, and also because it is claimed the cast-iron valves will withstand heat better than the forged valve. OIL ENGINES. THE CRANK-SHAFT bearing should be of such di- mensions as to allow a pressure of not more than 400 Ibs. per square inch on the projected area, and should be easily adjustable. These bearings are made either of brass or babbitt metal. The maximum pres- CAST IRON FIG. 21. sure, allowed on the piston-pin should not be more than 1000 Ibs. per square inch of projected area. THE ENGINE FRAME should be of substantial propor- tions and strongly ribbed to prevent vibration, or what is known as " panting," at each explosion. The frame is shown in section in Fig. 76. THE CRANK-PIN appears to be made of various ON DESIGNING OIL ENGINES. 43 dimensions in different types of engines; a short pin of large diameter is, however, recommended, the diam- eter being not less than 1.2 times the shaft. (See Table I.) The average pressure allowed is 500 Ibs. per square inch on the projected area. VALVE MECHANISMS. With the Beau de Rochas or four-cycle engine the valves are only operated dur- ing alternate revolutions of the crank-shaft. This necessitates an arrangement of some kind of two-to-one gear. Worm-gear, as shown in Fig. 22, is considered FIG. 22. to be well adapted for this work. The power necessary to operate the valves is, in this case, transmitted from the crank-shaft by the worm or skew gearing through the cam-shaft, with separate cams opening the air and exhaust valves by the operating levers, as shown in Fig. 23. Where spur-gearing (Fig. 230) is used the cam-shaft is mounted in bearings parallel to the crank- shaft, the cams then acting on the horizontal rod working in compression, which opens the valves. Various other arrangements for reducing the motion are also used, the work accomplished being in each 44 OIL ENGINES. case the same as with the worm or spur gear, shaft and levers namely, the opening of the valves during al- ternate revolutions of the crank-shaft. 'LINE VALVE BOX FIG. 23. In the two-cycle engine this valve or valves are operated each revolution of the crank-shaft by eccen- tric or cams actuated directly from the crank-shaft. FIG. 230. GOVERNING DEVICES. The governing devices for controlling the speed of oil engines are of two kinds : first, that designed to develop centrifugal force, which ON DESIGNI NGINES. 45 is balanced either by suitable controlling spring or dead weight, as shown in Fig. 24, and, secondly, the inertia or pendulum type of governor, in which a weight is FIG. 24. placed on a part of the reciprocating valve motion, and is so arranged as to have its movement controlled by a spring usually having adjustable tension. (See Fig. 26.) The. governors regulate the speed of the engine by the following different methods : (a) By acting through suitable levers or other mechanism on the valves controlling the fuel supply to the cylinder, either by means of a by-pass valve placed in the oil-supply pipe to vaporizer, thus allowing part of the charge of oil to return to the tank instead of entering the vaporizing chamber or by regulating the amount of oil as well as the air supply. (b) Acting directly on the oil-supply pump, length- 4 6 OIL ENGINES. ening or shortening the stroke of the pump, as re- quired. .(c) Where the oil vapor is arranged to be drawn into the cylinder with the incoming air the governor FIG. 25. acts on the exhaust-valve, holding it open during the suction stroke, thus preventing the inlet of vapor to the cylinder. (d) By acting on the vapor inlet-valve, allowing this valve to open only when an impulse to the piston is required. Engines driving dynamos for electric lighting and requiring very close regulation are preferably governed by the system of throttling or reducing the explosive pressures in the cylinder. Thus, when the engine ex- ceeds the standard speed for which the governor is set, only part of the vapor or oil is allowed to enter the ON DESIGNING OIL ENGINES. 47 vaporizing chamber or cylinder. The mixture of oil, o) I FIG. 26. vapor and air is accordingly regulated, and the mean effective pressure as required is suitably reduced. 4 8 OIL ENGINES. The indicator diagram illustrates the variation of the M. E. P. in the cylinder, as shown in Fig. 25, each expansion line registering a different pressure. No explosion is in this case omitted entirely, and conse- FIG. 27. quently the running of the engine is even and regu- lar. The hit-and-miss type of governor is shown in Fig. 26. This device is made in many different forms, the mode of working being similar in them all namely, ON DESIGNING OIL ENGINES. 49 the inertia of a weight controlled by the spring. When the speed of the crank-shaft is increased the weight is moved correspondingly quicker ; its inertia is then in- creased, and the strength of the spring is overcome sufficiently to allow the engaging parts of the valve motion to be disengaged during one or more revolu- tions, and consequently where this device acts on the oil-pump the charge of oil is missed; and no explosion takes place during the following cycle of operations. THE OIL-SUPPLY PUMP is placed against the oil-tank and base of engine or on bracket bolted to cylinder. It is usually made of bronze, with steel ball valves. Du- plicate suction and discharge valves are advantageous in case one valve on either side should leak. Fig. 27 represents oil-pump as used on the Hornsby-Akroyd oil engine. THE FUEL OIL-TANK is placed in or bolted against FIG. 28. the base of the engine. It is then made of cast iron as part of the base of the engine ; otherwise the tank is made of galvanized iron and separate from the engine 5O OIL ENGINES. base, so that it can be taken out when required for cleaning. A filter or strainer for cleaning the oil as it passes to the oil-pump is placed in the tank, arranged so as to be easily removed for cleaning, as shown at Fig. 28. HORIZONTAL AS COMPARED WITH THE VERTICAL TYPE OF OIL ENGINES. THE accessibility of the piston with the horizontal engine is considered a great advantage. The piston can always be seen and can be drawn out of the cylin- der and cleaned and replaced with ease in this style of engine, whereas in a vertical engine it is necessary to remove the cylinder cover, and perhaps other parts, to gain access to the piston, and also it is necessary to have sufficient head room above the top of the cylinder for chain-block to lift the piston and connecting-rod. The lubrication of the piston is also considered more effective in the horizontal than in the vertical type of engine. Furthermore, the connecting-rod is more ac- cessible for adjustment both at the crank-pin end and at the piston end in the horizontal type. This difficulty, however, has been overcome by arranging a removable plug in the cylinder casing, which when taken out allows access for adjustment to the piston end of the connecting-rod. European designers seem much in favor of the horizontal type of engines, and although some leading makers build the vertical type of engines, yet the greater number would appear to be made of the horizontal type. ON DESIGNING OIL ENGINES. 51 VERTICAL ENGINES for situations in buildings where space is restricted and where sufficient head room is available have the great advantage of occupying less floor space than the horizontal type. The mechanical efficiency of a vertical engine is somewhat greater, the friction of the piston being less than in the hori- zontal type of engine. The vertical type for some special purposes can, of course, only be used, but for ordinary uses the horizon- tal type of engine at present seems to be most in favor, one consideration being the difficulty of suitably ar- ranging the vaporizing and spraying details in the vertical type of engine, which are usually placed close to the cylinder, and are, therefore, not so fully under the control of the attendant as in the horizontal type. TWO-CYLINDER ENGINES. Objection is sometimes made against two-cylinder oil engines because of the increased number of working parts, which may possibly become deranged, and also be- cause of the exact adjustments which are considered necessary. The oil-supplying apparatus and all the mechan- ism required with a single-cylinder engine has to be duplicated with the two-cylinder type. In order that the work and wear on all crank-shaft and connecting- rod bearings may be exactly similar the same explosive pressures must be evolved in~ each cylinder. This necessitates close adjustment of the vapor supply. The governing mechanism (where one governor controls two different oil-supply devices) also requires fine ad- OIL ENGINES. justment, and provision has to be made for adjusting lost motion due to wear. FIG. 29. The two-cylinder engine, however, has many ad- ON DESIGNING OIL ENGINES. 53 vantages. In the first place, it receives an impulse each revolution of the crank-shaft, and consequently the energy of the fly-wheel is only required to maintain the normal speed of the crank-shaft during half a revolution, instead of the three strokes as required in the single-cylinder type. To obtain relatively the same power as with" one large cylinder, the two smaller cylin- ders cause less vibration at the foundation. The efficiency, however, of the two small cylinders is re- duced as compared with the one large cylinder, on account of the increased surface of cylinder cooling space. The two-cylinder engine, as shown in Fig. 29, has the oil-supply pump actuated from the crank-shaft instead of, as is usual, from the cam-shaft, an injection of oil thus being given at each revolution. The oil- supply pipe leading to each cylinder or vaporizer is fitted with check-valves, which are alternately opened by the pressure of the pump, being otherwise held closed by the pressure of compression and of explosion alternately in each cylinder.* ERECTING AND ASSEMBLING OF OIL ENGINES. The following remarks relating to the erection of oil engines contain a few hints on important points of this work, the information being intended for those * This method of fuel injection forms the subject-matter of U. S. patent 650,583, granted to the writer May 29, 1900. 54 OIL ENGINES. readers not sufficiently familiar with the assembling of explosive engines to be cognizant of the parts requiring careful handling and accurate workmanship. BEARINGS. In scraping in the crank-shaft bearings of horizontal engines the shaft must bear perfectly on that part of the bearings as shown in Fig. 30, marked FIG. 30. A, the greater pressure being on the part of the bearing which is between the centre line of engine drawn through the cylinder and the part through which the vertical centre line of fly-wheel is drawn. A slight play of about 1-64" can be given to the crank- shaft' sideways in the bearings in smaller-sized engines, and 1-32 of an inch in the larger sizes is recommended. ON DESIGNING OIL ENGINES. 55 In vertical engines the bearings receive both the pressure of explosion and the pressure due to the weight of the fly-wheels in the same part, and these bearings require the same care at those points in the lower half of the bearing namely, about 45 each side of the centre line drawn vertically through the cylinder and crank-shaft. The bearing surfaces of the caps and of that part where the pressure is not so great do. not require such careful scraping as those parts where the pressure is greater. PISTON AND PISTON-RINGS. The fitting of piston and piston-rings is very important and requires accu- rate workmanship. The cylinder and piston are machined to standard ring and gauge, one-thousandth per inch diameter of cylinder play being allowed. The metal of the piston not being of uniform thickness after machining may slightly lose its shape, and some- times requires slight hand-filing when being fitted to the cylinder. The piston without rings can be moved easily up and down inside the cylinder. If necessary the piston should be eased slightly by hand on the sides, being left a good and close fit at the top and bottom bearing in horizontal engines. The sides should not rub hard in any part. The piston, if the rings are in place, can be fitted to the cylinder from the back end of the cylinder, and can be moved around the front end, being inserted into cylinder as far as the rings. THE DISTANCE-PIECES or junk-rings should not touch the sides of the cylinder, the bearing of the piston be- ing- only on the trunk of the piston itself. The front 50 OIL ENGINES. part of the piston can also be bevelled for " in length, 1-32" in diameter, as shown in Fig. 14. THE PISTON-RINGS, if made as in Fig. 15, should have in the smaller sizes 1-32" play, in the larger sizes 1-16", as shown at A in Fig. 31. This space allows for expansion when the ring becomes heated in work- ing. It is advantageous to insert dowel-pins in the piston grooves to maintain the rings in the same posi- tion, so that the space in each ring is out of line with that in the following ring, as also shown in Fig. 31. \ Jl FIG. 31. THE PISTON is made in one piece, the rings being sprung on over the junk-rings. It should be remem- bered that with oil engines greater heat is evolved in the cylinder than in steam engines. Consequently the slightest play is allowed to the piston-rings at flie sides, and are, therefore, not made so tight a fit as in steam- engine practice. THE CONNECTING-ROD BEARINGS at piston end are ON DESIGNING OIL ENGINES. 57 scraped in the ordinary way, and should be allowed slight play sideways on the gudgeon-pin. In smaller- sized engines 1-64" can be allowed, this amount being slightly increased in the larger-sized engines. The crank-pin bearing of the connecting-rod is usually allowed a very slight play sideways also. THE AIR AND EXHAUST VALVES should not be a very close fit in their guides. If the fit in these guides is made too close when the valve-box becomes heated the consequent expansion may cause the valve-stem to stick in the guides, and leakage of the valve will result. The valve-seats are by some considered best left sharp, being not more than 1-32" wide before grinding. THE WATER-JACKETS of cylinder or valve-boxes should be all tested by hydraulic pressure to at least 1 20 Ibs. pressure per square inch before the piston is put into the cylinder. THE FLY-WHEELS require careful keying onto crank- shaft. If the keys are not a good fit and not driven home tight the engine may knock when running. Two keys in larger-sized engines are usually supplied, one being a sunk key, which is fitted to keyway in recessed shaft as well as to the keyway cut in the fly-wheel hub, the second key being only recessed in the fly-wheel and being concave on the lower side to fit the shaft. OIL-SUPPLY PIPES which have to withstand pres- sure should have the fittings " sweated" on, the unions being screwed into place -on the brass or copper pipe while the solder is still in a liquid state. CYLINDERS made of two or more parts require the joints of internal sleeve to be made with great care. 58 OIL ENGINES. Asbestos or a copper ring is used to make this joint ; sometimes wire gauze with asbestos is used, which has been found to give very good results. [Tables giving the Calorific Values of Oils, etc., will be found at end of book.] CHAPTER III. TESTING ENGINES. THE chief object in testing explosive engines at the factory is to ascertain that, in actual working at dif- ferent loads, the several adjustments are correct. In the steam engine a physical process is completed, re- quiring only the inlet, expansion, and the outlet of the steam to and from the cylinder, whereas in the oil engine a chemical process is gone through consisting of the introduction of the proper mixture of vaporized oil and air into the cylinder, the ignition of this ex- plosive mixture and the consequent combustion. All this must be accomplished before the piston receives an impulse. In order, therefore, that the best results be obtained, the different mechanisms controlling these processes are each set, and record of their performance during the test is taken with the indicator, which results are again verified by some form of brake attached to the fly-wheels or pulley of the engine, and are further checked in an oil engine by the record of the amount of oil which is consumed for the power developed. Where more detailed tests are required, the tempera- ture of the exhaust gases, the amount of air consumed in the cylinder, its temperature and barometrical pres- 6o OIL ENGINES. sure, together with the amount of cooling water neces- sary to keep the cylinder to the required temperature, are each noted and recorded. When the test is made with a new engine, it should be first started up and run without anv load for a short time. The cams are set as FIG. 32. shown in diagram, Fig. 32, for engines having both air and exhaust valves actuated from the crank-shaft. The air-valve closes, as shown, just after the crank-pin has passed the out centre, the exhaust-valve opening at about 85 per cent, of the full stroke and closing just TESTING ENGINES. 6l after the air-valve has opened. Where the air-inlet valve is automatic the exhaust-cam only is set, as shown in the diagram, and the air-valve spring should be adjusted so that the incoming air is not choked in passing the valve during the suction stroke. The oil-pipes leading to the vaporizer or sprayer should be well washed before starting the engine, as with a new engine grit and filings may get into the pipes, and when the engine is started the oil-valves and valve-seats may be damaged. The oil-filter also must be in proper shape and clean, so that the oil can flow freely to the oil-pipe. After the vaporizer and igniter has been well heated a little oil should be allowed to enter the vapor- izer or combustion chamber; then the fly-wheels can be turned forward a few times, after which the engine should start freely. The method of starting the differ- ent types of engines is explained in detail in Chap- ter VII. An engine is sometimes found difficult to start the first time owing to some defect in the castings or workmanship, and if it fails to start, the engine should be examined in detail to ascertain the cause. First test the oil-inlet or spraying device by hand; then test the pressure of compression in the cylinder by turning the fly-wheels backward. The relief-cam being out of action, it should not be possible with full compression to turn the fly-wheel past the back centre. If the compression is so slight that the pressure in the cylinder can be overcome and the fly-wheel turned during the compression period by hand, then either the piston-rings are leaking or there is leakage past TESTING ENGINES. 63 the air and exhaust valves or through some of the joints or gaskets. Air and exhaust valves and piston- rings should be examined, and any appearance of leak- age remedied by refitting the piston-rings, as already explained in Chapter II., and the valves, if necessary, should be reground in. New engines also fail to start at times by reason of the leakage of water from the cooling jacket into the cylinder owing to faulty gas- kets or flaws in the castings. This leakage of water may sometimes be ascertained by failure to obtain an explosion in the combustion chamber when all condi- tions in the cylinder and vaporizer are apparently in good order for the engine to start properly. If leakage of water is suspected but cannot be detected in this way, the water-pressure pump should be attached and the water-jackets tested to a pressure of 120 Ibs. The crank-shaft and other bearings require careful oiling at first, and full lubrication should be given to the piston ; otherwise it may, perhaps, work dry and cut the cylinder. After working a few hours, the piston should be withdrawn and examined ; any hard places on the sides should be eased either by careful hand filing or other- wise. The junk-rings (or distance-pieces between the rings) should be eased if necessary, so that they do not work hard on the cylinder. The full bearing of the piston should be from about \" from rings forward to within |" of the front end, as already explained in Chapter II. The terms " brake," or- " developed," or " actual" or " effective" H. P., are synonymous, and are used 64 OIL ENGINES. to signify the power which an engine is capable of delivering at the fly-wheel or belt-pulley. This power is variously designated, and here we shall use the ab- breviation B. H. P. to express it. The indicated H. P. represents the whole power developed by combustion in the cylinder, but it is not considered such a reliable method of measuring the power of explosive engines as that of the dynamometer or brake, because the in- dicator-card only gives the power developed by one or more explosions, whereas the brake can be applied for any length of time and shows the average performance of the engine for a longer period of time. Fig. 33 illustrates the engine as arranged for testing in the factory. The fuel tank shown at the left hand is placed there for the purpose of running the oil-con- sumption test. The fuel pump is connected tempo- rarily to this tank instead of taking its supply of oil from the tank in the base of the engine. The indicator is also shown in place on the top of the cylinder. The device for reducing the stroke of the crank to suitable dimensions for the indicator is also shown in place bolted to the bed-plate of the engine. The brake con- sists of rope \" thick, with wooden guides with bal- ances at each extremity. The upper balance is sus- pended by adjustable hook suitably arranged for alter- ing the load on the brake. Various kinds of dynamometer brakes are used for testing ; that shown in Fig. 33 is considered by the writer as being satisfactory. The brake should be attached as shown in the illustration, the load being taken as the number of pounds shown on the upper TESTING ENGINES. 65 scale less those shown on the lower scale. Brake or actual H. P. is calculated thus : B. H. P. IV X C X N 33,000 W = net load in pounds. C = circumference of wheel. N number of revolutions per minute. FIG. 34- The circumference of the wheel should be measured at the centre of the rope, thus allowing for half the rope thickness. INDICATORS. Fig. 34 shows the American Thomp- son Improved Indicator with J" area piston. 66 OIL ENGINES. THE INDICATOR is attached to the cylinder by first screwing into the cylinder the indicator cock, as shown at Fig. 340, to which the indicator is applied in the ordinary way. The length of the stroke of the engine must be re- duced to suit the dimensions of the diagram, which is FIG. 34a. usually about 3" long. This is accomplished by the use of a device, as shown in Fig. 35. Indicated H. P. is calculated thus : PLAE I.H.P.=- 33,000 P = mean effective pressure in Ibs. L = length of stroke in feet. A = area in inches of piston. E = number of explosions per minute. TESTING ENGINES. 67 The M. E. P. of indicator-card is obtained by the use of the planimeter, as shown in Fig. 37, or by meas- uring the card by scale and taking the average pres- sure. The illustration (Fig. 36) shows the design and FIG. 35. arrangement of the parts of the Crosby gas-engine in- dicator. The cylinder proper is that in which the movement of the piston takes place. The piston is formed from a solid piece of tool steel, and is hardened to prevent any reduction of its area by wearing. Shal- 68 OIL ENGINES. low channels in its outer surface provide an air pack- ing, and the moisture and oil which they retain act as lubricants, and prevent undue leakage by the piston. The piston is threaded inside to receive the lower end of the piston-rod and has a longitudinal slot which permits the bottom part of the spring with TESTING ENGINES. 69 its bead to drop on to a concave bearing in the upper end of the piston-screw, which is closely threaded into the lower part of the socket; the head of this screw is hexagonal, and may be turned with a hollow wrench. The swivel-head is threaded on its lower half to screw into the piston-rod more or less according to the required height of the atmospheric line on the diagram. Its head is pivoted to the piston-rod link of the pencil mechanism. The pencil mechanism is designed to eliminate as far as possible the effect of momentum, which is especially troublesome in high-speed work. The movement of the spring throughout its range bears a constant ratio to the force applied, and the amount of this movement is multiplied six times at the pencil point. SPRINGS. In order to obtain a correct diagram, the height of the pencil of the indicator must exactly represent in pounds per square inch the pressure on the piston of the oil engine at every point of the stroke ; and the velocity of the surface of the drum must bear at every instant a constant ratio to the velocity of the engine piston. THE PISTON SPRING is made of a single piece of spring steel wire, wound from the middle into a double coil, the spiral ends of which are screwed into a brass head having four radial wings to hold them securely in place ; 80 to 200 Ib. spring is a suitable pressure for this work. This type of indicator is- ordinarily made with a drum one and one half inches in diameter, this being 70 OIL ENGINES. the correct size for high-speed work, and answering equally well for low speeds. To remove the piston and spring, unscrew the cap ; then take hold of the sleeve and lift all the connected parts free from the cylinder. This gives access to all the parts to clean and oil them. To change the location of the atmospheric line of the diagram. First, unscrew the cap and lift the sleeve, with its connections, from the cylinder ; then turn the piston and connected parts toward the left, and the pencil point will be raised, or to the right and it will be lowered. One complete revolution of the piston will raise or lower the pencil point -J", and this should be the guide for whatever amount of elevation or depression of the atmospheric line is neede.d. To change to a left-hand instrument. If it is desired to make this change-: First, remove the drum, and then with the hollow wrench remove the hexagonal stop screw in the drum base, and screw it into the vacant hole marked L ; next, reverse the position of the adjust- ing handle in the arm ; also, the position of the metallic point in the pencil lever; then replace the drum, and the change from right to left will be completed. The tension on the drum spring may be increased or diminished according to the speed of the engine on which the instrument is to be used, as follows: Re- move the drum by a straight upward pull ; then raise the head of the spring above the square part of the spindle, and turn it to the right for more or to the left for less tension, as required ; then replace the head on the spindle. TESTING ENGINES. ?! Before attaching the indicator to an engine, allow air to blow freely through pipes and cock to remove any particles of dust or grit that may have lodged in them. The indicator should be attached close to the cylin- der whenever practicable, especially on high-speed en- gines. If pipes must be used they should not be smaller than half an inch in diameter, and as short and direct as possible. The indicator can be used in a horizontal position, but it is more convenient to take diagrams when it is in a vertical position, and this can generally be ob- tained, when attaching to a vertical engine, by using a short pipe with a quarter upward bend. The motion of the paper drum may be derived from any part of the engine, which has a movement coinci- dent with that of the piston. In general practice and in a large majority of cases the piston itself is chosen as being the most reliable and convenient. When the indicator is in position and the cord-drum or other reducing motion is correctly placed, it is next necessary to adjust the length of the cord, so that the drum will clear the stops at each extreme of its rota- tion. The engine should be allowed to run for a few minutes to heat up before taking a diagram. The at- mospheric line should be drawn by hand, preferably after the diagram has been taken and when the instru- ment is heated up ; the card is then taken with full- rated load on the brake. It is well to allow the pencil to go several times over the paper so as to procure a card showing several explosions, and thus the aver- age pressure can be taken. OIL ENGINES. The pressure of the pencil on the paper can be ad- justed by screwing the handle in or out, so that when it strikes the stop there will be just enough pressure on the pencil to give a distinct fine line. The line should FIG. 37- not be heavy, as the friction necessary to draw such a line is sufficient to cause errors in the diagram. THE PLANIMETER or averaging instrument is shown at Fig. 37. No. i planimeter is the simplest form of the instrument, having but one wheel, and is designed to measure areas in square inches and decimals of a TESTING ENGINES. 73 square inch. The figures on the roller wheei D repre- sent units, the graduations tenths, and the vernier E gives the hundredihs. F is the tracer and P is the pivot. Fig. 37 represents the No. 2 planimeter, which is the same as the No. I, with the addition of a counting disc G, the figures on which represent tens and mark complete revolutions of the roller-wheel. By this means areas greater than ten square inches can be measured with facility. The result is given in square inches and decimals, and the reading from the roller wheel and vernier is the same as with No. I. Fig. 37 represents the No. 3 planimeter, which dif- fers somewhat in design from the two previously de- scribed. It is capable of measuring larger areas, and by means of the adjustable arm A giving the results in various denominations of value, such as square deci- meters, square feet and square inches ; also of giving the average height of an indicator diagram in fortieths of an inch, which makes it a very useful instrument in connection with indicator work. DIRECTIONS FOR MEASURING AN INDICATOR DIAGRAM WITH A NO. I OR NO. 2 PLANIMETER. Care should be taken to have a flat, even, unglazed surface for the roller wheel to travel upon. A sheet of dull-finished cardboard serves the purpose very well. Set the weight in position on the pivot end of the bar P, and after placing the instrument and the diagram 74 OIL ENGINES. in about the position shown in Fig. yja, press down the needle point so that it will hold its place, set the tracer ; then at any given point in the outline of the diagram, as at F, adjust the roller wheel to zero. Now fol- low the outline of the diagram carefully with the tracer FIG. 370. point, moving it in the direction indicated by the arrow, or that of the hands of a watch, until it returns to the point of beginning. The result may then be read as follows : Suppose we find that the largest figure on the roller wheel D that has passed by zero on the ver- nier E to be 2 (units) and the number of graduations that have also passed zero on the vernier to be 4 TESTING ENGINES. 75 (tenths), and the number of graduation on the vernier which exactly coincides with the graduation on the wheel to be 8 (hundredths), then we have 2.48 square inches as the area of the diagram. Divide this by the length of the diagram, which we will call 3 inches, and we have .8266 inch as the average height of the dia- gram. Multiply this by the scale of the spring used in taking the diagram, which in this case is 40, and we have 33.06 pounds as the mean effective pressure per square inch on the piston of the engine. DIRECTIONS FOR USING THE No. 3 PLANIMETER. No. 3 planimeter is somewhat differently manipu- lated, although the same general principle obtains. The figures on the wheels may represent different quantities and values, according to the particular ad- justment of the sliding arm A. If it is desired merely to find the area in square inches of an indicator dia- gram, set the sliding arm so that the lo-square-inch mark will exactly coincide with the vertical mark on the inner end of the sleeve H at K. The sliding arm is released or made fast by means of the set-screw 5\ With the wheels at zero and the planimeter and dia- gram in the proper position, trace the outline carefully and read the result from the roller wheel and vernier, the same as directed for the No. i and No. 2 instru- ments. THE INDICATOR-CARD shows what is occurring inside the cylinder and combustion chamber during the differ- ent periods of the revolution. It gives a record of the 76 OIL ENGINES. variations in pressure, and also the exact points of the opening and closing of the valves. With the Otto or Beau de Rochas cycle the four strokes are as follows : Suction (A), compression (B), expansion (C), ex- haust (D). The lines in the diagram are correspond- ingly lettered (see Fig. 38), and they represent each of these processes. EXHAUST " ^ _ATMOS. SUCTION A. FIG. 38. Fig. 39 shows a good working diagram, in which the mixture of air and hydrocarbon gas is correct and where combustion is practically complete. The igni- tion line in this diagram is nearly perpendicular to the atmospheric line, but inclines slightly toward the right hand at top. The diagram also shows the open- ing of the exhaust-valve at the proper time namely, at 85 per cent, of the stroke. The compression line represents the proper pressure, and the air-inlet and exhaust lines indicate correct proportioned valves and inlet and outlet passages. TESTING ENGINES. 77 In considering and analyzing diagrams the follow- ing hints will perhaps be of service. If the suction line of the diagram is shown below the atmospheric ATMOS. FIG. 39- FIG. 40. line, as in Fig. 40, then the air-inlet to the cylinder is known to be in some way choked. Where the air-valve is automatic this defect may be caused by the valve- 7 OIL ENGINES. spring being too strong and it accordingly requires weakening ; or the area of the air suction-pipe, if this is used, may be too small or this connection may have too many elbows or bends in it, and should be either of in- creased diameter or the bends should be eliminated. Again, the valve itself may have too small an area, or if actuated have insufficient lift (the proper lift of a valve is J of its diameter), or the period of opening of the valve may not be correct, and the setting of the cams should be carefully examined, and, if necessary, altered in accordance with the diagram of valve open- ing, as shown at Fig. 32. If the compression line B shows insufficient pres- sure of compression, this indicates leakage, which is probably due either to leaky piston or valves. If this leakage is past the piston-rings, the escaping air may be heard and the lubricating oil will be seen at each ex- plosion period to be splashing and blown past the rings of the piston. If no signs of piston leakage are noticed, then examine oil-inlet air and exhaust valves and valve- seats very carefully ; also note the various joints in the valve-box and otherwise where leakage might possibly occur. In engines without water-jackets around the valve-box the heat of the exhaust gases continually passing through the valve-chamber may sometimes cause the valve-seats to expand unequally when heated, and consequent leakage will occur when working. If leakage is detected at the valves they must be re- ground, and also any hard places on the valve-stems or guides where they become heated should be eased so that the valves will work easily and efficiently when the TESTING ENGINES. /9 seats and guides are expanded, and, perhaps, slightly distorted, by the heat of working. (It is understood that these remarks refer to new engines solely.) With some engines means of increasing the compression by movable plates on the connecting-ro(J crank-pin end or other somewhat similar means are provided which can be changed, if necessary, thus decreasing the FIG. 41. amount of clearance in the cylinder. If the piston- rings are without leakage and they have worked into their proper bearings in the cylinder, and if all the valves are in perfect order and without leakage, and still the compression pressure, as shown on the diagram and as already explained* requires increasing, then the clearance in the cylinder can be slightly decreased where it is possible to do so. The vertical ignition line shows the timing of the ignition, and also the initial pressure of explosion. If this line is as represented in Fig. 41 the ignition is known to be too early, and should be arranged to occur somewhat later. The 8o OIL ENGINES. diagrams as shown in Fig. 42 has the ignition line too late. The timing of the ignition is regulated as follows : With electric ignition by altering the period of ATMOS. FIG. 42. sparking. Thus, if later ignition is required the ignit- ing device must not be allowed to spark till the crank- pin has travelled nearer to the dead centre. With the hot-tube ignition and no timing valve, the length of the TESTING ENGINES. 8l tube can be changed. For example, to retard the ignition the tube should be lengthened slightly and its temperature somewhat decreased. In engines where neither of these means of ignition is used, but where the ignition is caused by the heat of the vaporizer- chamber or somewhat similar device, the timing of the ignition is controlled by the heat of the vaporizer- chamber and also by the heat generated by the process of compression. Where the ignition in this case is to be retarded, the compression should be reduced slightly and the vaporizer or other igniting device maintained at a less heat. The ignition/ however actually caused, is always influenced by the heat of the cylinder walls and the temperature of the incoming air, which corre- spondingly increases or decreases the heat caused by the compression before explosion takes place. The ignition is usually adjusted when testing engines with the cooling water issuing from the cylinder water- jackets at a temperature of 110 to 130 Fahr. The expansion line is marked C, as shown in Fig. 38. This line indicates the initial pressure of combustion, and it also shows the developed pressure decreasing as the volume of the cylinder becomes greater with the piston moving forward. The effective pressure devel- oped is measured from this line to the compression line, and varies according to the richness of the ex- plosive mixture. When the engine is in actual use the governor controls this pressure automatically. The mean effective pressure is greater in some types of engines than it is in others, and varies, as stated in Chapter II., from 40 to 75 Ibs. The amount of the 82 OIL ENGINES. pressure in the cylinder is dependent upon the method of vaporization, upon the proper mixture of the gas ATMOS. FIG. 43. and air before explosion, and also upon the pressure of the compression. As in gas engines, the tendency in oil-engine practice is toward higher compression to TESTING ENGINES. 83 increase their efficiency. Where the mean effective pressure is low the relative power of the engine will, of course, also be reduced. The greatest mean effective pressure should be attained when the oil is thoroughly vaporized, is properly mixed with the air and when the compression is as high as practicable without pre- ignition taking place. Should the exhaust lines D appear as in Fig. 43, then it is understood that the discharge of the exhaust gases is in some way choked ; this may be caused by the ex- haust-valve itself being too small, or to the s periods of the opening of the valve being incorrect. (See dia- gram, Fig. 32.) Again, this defect may be caused by too many sharp bends, too small diameter exhaust- pipe, or possibly too long an exhaust-pipe. Theoreti- cally no back pressure should be allowed during the exhaust period, but usually in practice a slight pres- sure of about one pound is recorded. Each pound per square inch of back pressure shown by the exhaust line shows a back pressure in the cylin- der, which is negative work to be overcome by the piston, and represents a slight loss of power by the engine. Care must be taken that the indicator is in proper condition, without any play in the pencil arm, and that the piston is free and well -lubricated. Lost motion in the indicator may show peculiarities in the diagram which to an inexperienced manipulator may be the cause of trouble. TACHOMETERS (Fig. 44), These instruments have been designed for the purpose of ascertaining at a 8 4 OIL ENGINES. glance the number of revolutions made in a given time by rotating shafts. Their construction is based on centrifugal power, and they consist of a case inside of which are mounted a pendulum ring, in connection with a fixed shaft, a sliding rod and an indicating FIG. 44. movement. The apparatus is very sensitive, ?nd will indicate the slightest deviation in speed. PORTABLE TACHOMETER (Fig. 440). This instru- ment is similar in construction to the tachometer for permanent attachment. By applying it by hand to the centre of rotating shafts, it will instantly and correctly indicate the number of revolutions of the shaft per minute. Fig. 44& illustrates a new form of speed counter, the TESTING ENGINES. invention of Mr. A. J. Hill, of Detroit, Mich., which, besides counting, also registers the number of revolu- FIG. tions of the shaft. This is accomplished by simply punching a continuous slip of paper, as shown in 44b. Fig. 443 co m -3- ci "J- r^ OO 5 | Sujjnp aanssajd u^aj^ M M CM ^- in t^co o^ co W tf P a l0 o 3 ,o N aiv m ON Oco O in w in rf O '* tJ cc CO M a^saadaanssaadu^K M . o> M CU 9 .n, Q Oco r^ m coo coo m co 04 33 ajtoa^s J3< ^ a-inssajfj unaj\[ M M M M -VARIOUS paioo3 ^N J IV mi AV auinpA co O O co -jf co O^ Q^cO CO CO O O m TJ- Tt 1 w j m aan^Bjadmax ^UB;S -uo3 ye aiy il^JAv auinp^Y O O O4d<4 W i B O w W co^j-mO mo mo M M N M CO OIL ENGINES CONNECTED TO AIR-COMPRESSORS. 127 uiO*/iOr>Or>O*r>O*r>O"">Ou~>O*r>O*r>Ou">Ou~>O O O O O O en -}- -t m vno O t^r^cooo O O O O w w M M en en Tt -1- mo r^co o O ..MM O r^* m o m o M r^ o M m o t^ oo O O O O O O O r^ ^ O r^ M co O M en m r-^ co O M en-rmt^co OO *-i M ^i-mo rococo O M -i-m M cnenenenenenrf'^"-^l-' r 1--^'^*^Tinininvnininininin O in ir> co oco rt rt M r^ en r^ m vnco ON O O^co cot^iovnc^ r^-Moo r--co ^O M c c> cnTTunoo rcoco o^ o\ O oo vno en O t^ M en O -O <^oo M r-^ao r^ M O r^cnco ^-o^C^cnco MO O c5 w ci to ^ rcoco ^O O w >-< N cncn--'-t'vnu-io rr-c oco r^o m rf ^ en M M M o O oococo r^t^o \r> \r, C4aMWMM^?WMMMMMM)HMMOOO C O C Oo'o' o" " 00 C^O O -too MOO -3-ao MOO rl-co MOO -^too MO O cO O -J- M rrt-ccoco OOOO O O M M M enen-f ^OrfO^rOrfO-tO'-rO'^-O-^O'^-O-^---r-t-i--i- t^r^coco OOO O M M M M enen'TTmmo r^cc oo MMMMMWMMMMMMMMMWM ^nOmOmOir>OmOvr>O ir>OmO O O O O t^oooo OOO O M M M M enen-^^-mo r^oo o OIL ENGINES CONNECTED TO AIR-COMPRESSORS. I2Q For example, in the 8J X 8J inch single-acting direct-connected plant (Fig. 59); the theoretical power required to actuate the compressor is as follows : H. P. = 19.4 X -78 X 567 X 230 33,000 H. P.= 5.98. As this represents only the power required to com- press the air, additional power must also be provided sufficient to overcome the friction of the compressor. In this case it will be noted that approximately 15 per cent, is allowed. TABLE III. EFFICIENCIES OF AIR-COMPRESSORS AT DIFFERENT ALTITUDES. Barometric, Pressure. '%**- g >, t/3 " tw * <- *-* n Decreased Altitude, feet. EgSS Jlf ^wo sis >% Power Required, Per Cent Inches, Mercury. Pounds Per Square Inch. O 30.00 14-75 100. 0. 0. IOOO 28.88 14.20 97- 3- 1.8 2OOO 27.80 13.67 93- 7- 3-5 3000 26.76 13.16 90. 10. 5-2 4000 25.76 12:67 87. 13- 6.9 5000 24.79 1 2. 2O 84. 16. 8-5 6000 23.86 n-73 81. 19. IO. I 7000 22.97 11.30 78. 22. ii. 6 8000 22.11 10.87 76. 24. I3-I 9000 21.29 10.46 73- 27. 14.6 IOOOO 20.49 10.07 70. 30- 16.1 I IOOO 19.72 9.70 68. 32- 17-6 12000 18.98 9-34 65- 35- 19.1 13000 18.27 8.98 63- 37- 20. 6 14000 17-59 8.65. 60. 40. 22.1 15000 16.93 8.32 58- 42. 23-5 OIL ENGINES. OIL ENGINES CONNECTED TO AIR-COMPRESSORS. 13! The efficiency of an air compressor is reduced when working at high altitudes. Table III. gives such de- preciation in efficiency at the different altitudes. OIL-ENGINE PUMPING PLANTS. Fig. 61 represents an oil-engine pumping plant as installed for supplying FIG. 62. town or village water-supply. This outfit consists of 13 H. P. oil engine connected by friction-clutch to the shaft of a triplex pump having cylinders 6J" diameter and 8" stroke. The amount of water delivered by this outfit is ap- proximately -165 gallons per minute, with total aver- age lift of 195 ft. The cost of fuel for running is I3 2 OIL ENGINES. about 13 cents per hour. Practically, no attention is required beyond starting the engine and occasional lu- brication. Fig. 62 shows a small outfit suitable for supplying water to a country-house, and consists of i^ H. P. engine and pump capable of delivering 1200 gallons of water with 150 ft. total lift. To calculate the theoretical H. P. required to raise a FIG. 63. given amount of water, multiply the number of gallons to be delivered per minute by 8.3, which gives the weight; again, multiply by the total required lift in feet, and divide the result by 33,000, thus : Number of gallons X 8.3 X height of lift H. P. = 33,000 OIL ENGINES CONNECTED TO AIR-COMPRESSORS. 133 Example: 165 gallons 195 feet lift 165 X 8-3 X 195 33,000 = 8 H. P. actually required to lift water. The friction of the moving parts of the pump has to be overcome, and for this and other losses allowance is usually made by figuring the efficiency of the pump (in the smaller size) at 60 per cent, to 70 per cent. OIL ENGINES DRIVING ICE AND REFRIGERATING MACHINES. Oil engines are now being used in connection with small ice and refrigerating machines. Fig. 63 represents a plant of this description, con- sisting of an oil engine belted direct to a refrigerating machine used in this instance for cooling a butcher's cold-storage box. The refrigerating machines are rated according to the -amount of ice they are assumed to displace. A one-ton machine is one which will effect the same cooling in twenty-four hours which a ton of ice would do in melting. The chief advantage of the refrigerat- ing machine is that while the ice can only produce a temperature of 35 Fahr. and upward, the refrigerat- ing machine can be operated to produce any tempera- ture which may be desired. In the process of refrigeration, the work which the 134 OIL ENGINES. oil aigine has to do is to drive a compressor, and there- fore the same principles may be applied to this machine as to the ordinary air-compressor already discussed. We need only to know how much gas has to be com- pressed and the conditions upon which to base the cal- culation for the work done in the compressor. It is the practice of refrigerating-machine makers to allow about 4.5 cubic ft. displacement per ton of refrigera- tion that is to say, a lo-ton machine is one having capacity of pumping 45 cubic ft. of gas per minute. In the case of the ordinary compressor, we have only to consider the final pressure, since the initial pressure is always that of the atmosphere. In the case of the refrigerating machine, however, this is not the case, for the gas being circulated in a closed circuit may have not only a varying final pressure, but also a vary- ing suction pressure. These pressures depend upon the temperatures obtaining in the cold room and in the condenser in a manner which it is not necessary to consider in detail. The initial pressure and the final pressure being known, the mean pressure may be cal- culated in the ordinary way. To facilitate this calculation, table No. IV. may be consulted. The vertical left-hand column gives the initial pressure corresponding to the temperatures named in the second column, these being the tempera- tures inside the cooling pipes. The top horizontal line gives the pressure corresponding to the temperatures in the second horizontal line. These temperatures are those obtaining in the condenser. OIL ENGINES CONNECTED TO AIR-COMPRESSORS. 135 00 C\OOONOQ^w ON O O O 00 O ON M ON ON ON N N w 10 "* 00 OVOO N 10 O\ N VO 00 M CO T- t^t^r^oOOOOO O\ ON Os rj- O ^ torj-M 000000 ioO\i>- tovovo M ON ON 00 IO OO' M PT t^. t^ oo oo co oo oo H- 00 >H vo" 06 M' oo M vo* o a\ o a 00 OO O to O vo ^O to to to VO M3 MS VO 8 j? t> O MCOVO OO 10 10 o 10 OCOOO IOIO>OVOVOVO m to to to 10 to 10 to to to OOOO tovofO Ot^-O roro M 10 ^-. ^MDfO 10 10 tototo m MDrj-rf rtOOOO . o coco ftO I-- aucns^OBig <^co O 01 O ^ O O M vn co 01 M O - co coco co vn vn vn 01 ft r^ co 01 M vn r^ '3 3? ^\ M r-co coo CO ON O ONCO o aucnsn^ia M oo O vn ft -t M CO 01 01 o ' ft 3 % ^ CO O M ft co 01 vn 01 coco fto vn ON vn co M O ft co ON CO O CO s M o vn ft co 01 CO M 01 M M ft co co O co M co oo co vn co 01 ^ 3 3? s^ M M O 01 CO co r^co O co M UOSIiail 9 } S H t-01 co vn M ft M M CO 01 CO N ft co CO . -03 auiSug NN XN t^ ftO O co vno co coco co co co 00 ON co SBO ipqduno ONCO CO ft W M O t^ M \O CO 01 j 03 auiSug XN XN co ft O co ft ON f~-* Ol CO ON ON Ol O 01 vn vn vn ft 01 M co r- Ol ft vn vn SJB O liaqdui'B3 Ol M co 01 M r^ O vn M 01 M co o vn M CJ M 01 M MM M Ol CO J-N. pn NN vn 01 r^ o O M O coo vn r^ O O vnco co O co O 'soag Aaissoj3 O co vn N O MM M l^-OO M O ft co GO 8 '..Q.Q o ^^Q g g 43 : *^"] "'-' C fl .. ""- 1 c d ' < h3 D tJ - '^ e T3 J ZZ p t P| H ~ ^ Pi QH ^ ^ w ENGINES. Diameter of cylinder, i Stroke, inches . eo M in r^ r-- r^ in 00 xn 1 I 1 1 ' *l TfO t-^co r^co MO CO M M JWi^S, ^ in co in xn mo H? M M' 8 S 2 Ooo 1 1 1 1 n ^i 1 M ,,, 9 ^ Tt xn M O t^oo O M O O rf-co xn O co M O M CO O M M MM M M in co -f M 't>i tCO MOM O CO M Russolene CO OO M xn r-* O co in '3 3 -to in 'tO COO t-co co rt- O M M O ^t M O M co co in xn TfO co Oco O M ^t M xnoo M Russolene in in o O M M Tj- rf co O O t"* 1 CO 03 ^ o ^ **"* co M Q M in co 03 auiSug -t -t M m t^ co t~>- O coo co xn r* M in Q co in Oco M 1 1 1 1 1 co 8 1 " WgSfe Tt M CO co co xn O r-~ rf m ooo co M O M CO CO M M MM xn M M M M xn CO oo r^ of " Russolene O CO O GO O M O O M .W^o.0 o coco co xn in xn M -f co M *t xn MM MOM M MM O co M M M xn o H xn M O r^ 5^.S 4^-0^ &'% O co M Q CO O m M CO M O ENGINES. Duration of trial hours Time taken to start full load, miuutes. . BRAKE HORSEPOWER : : : : c . > : : : ' % : : A s_ p> ffipq H-5 P3 i* Circumference of flywheel, effec Load on brake, Ib Spring balance reading, Ib Net load on brake, Ib Revolutions per minute, mean. . Brake horsepower INDICATED HORSEPOWER Diameter of cylinder, inches. . . Stroke, inches. . . Mean effective pressure, Ib. per Explosions per minute, mean . . . Indicated horsepower Mechanical efficiency OIL CONSUMPTION : 13 1 VM O fi O U i Q .G :^H '. M 1 fe sl 02H TABLE VII. CALORIFIC POWER OF VARIOUS DESCRIPTIONS OF PETROLEUM, ETC. (B. REDWOOD.) Description of Oil. Specific Grav- ity at o C. Chemical Com- position. Coefficient of Expansion. Am't of Water Evaporated Per Unit of Fuel. | d e.t! 1~ wS 10, I 80 10,223 9.963 10,672 9.771 10,121 9,708 IO,O2O 10,458 c o e u 83-5 84.3 82.0 84.9 83-4 84.0 86.9. 85.7 86.2 79-5 80.4 86.2 82.2 85-3 80.3 82.0 87.4 86.3 86.6 87.1 87.1 87.1 I* ffi* C V bo X Heavy Petroleum from West Virginia 0.873 0.8412 0.816 0.886 0.820 0.786 0.912 0.892 0.861 0.829 0.892 0-955 0.870 0.885 0.911 1.044 0.822 0.844 0.938 0.928 0.923 0.985 13-3 14.1 14.8 13-7 14.7 13-4 ii. 8 12. 13-3 13-6 12.7 II.4 12. 1 12.6 II-5 7 .6 12.5 I 3 .6 12.3 ii. 7 12.0 IO.4 3- 2 1.6 3-2 1.04 1.9 1.8 J -3 2-3 0-5 6.9 6.9 2.4 5-7 2.1 (N. 0.) 8.2 (0. S. N.) 10.4 O.I O.I I.I 1.2 0.9 2-5 0.00072 0.000839 0.00084 0.000721 0.000868 0.000706 0.000767 0.000793 0.000858 0.000843 0.000772 0.000641 0.000813 0.000775 0.000896 0.000743 0.000817 0.000724 0.000681 0.00091 0.000769 0.0008685 14.58 14-55 14.05 15.30 14.14 13.96 14.30 14.48 I5-36 Light Petroleum from West Virginia. Light Petroleum from Pennsylvania Heavy Petroleum from Pennsylvania American Petroleum.. Petroleum from Parma Petroleum from Pech- elbronn . ... Petroleum from Pech- elbronn Petroleum from Schwabweiler Petroleum from Schwabweiler Petroleum from Han- over Petroleum from Han- over Petroleum from East Galicia 14.23 14.79 12.24 12.77 16.40 15-55 15.02 14.75 IO,O85 10,231 9,046 8.916 11,700 11,460 10,800 10,700 IO,83I 10,081 Petroleum from West Galicia Shale Oil from Ardeche Coal Tar from Paris Gasworks Petroleum from Balak- hany Light Petroleum from Baku. Heavy Petroleum from Baku. Petroleum residues from Baku Factories Petroleum from Java. . Heavy Oil from Ogaio n f! a D-i v O ^ fri J o d d d d o" d cco"o ^ TJ 1 % " 000 s -s 5*jj as+j 00 a vo ro t^ P> d d vo O M "S. vc t^oo oo t^ t^ d d d d d o o ccO-i ts \ i %4 : ^> S .j.A 6 M d d H oo vo q t-. ^ ro C ^ -M HH CTi |SJ w M 5 ? 2" 2" 2 JT 2 2" 2 h? 2 6-2*" u OO -^ IT) 10 &g#8 .T ^ J 5 |ifj d d d o d d d d 00 ti d d >i 00 d *0 oo" 5o 00 t^ 00 d d d K 8 o? 00 00 C^ O^ dodo ^ a OO 00 d d oJ fi-j i ro IO IO IO ro ro ro a ! 1* 1 ro oo d 00 OO 00 d d d CO N N ^ 00 O> 00 O- 6 6 6 6 d d CC o O O o o o o o (8 cJ 2 i ! ! ; ; 6 N ': ty, | : 3 - J : : : : ct : * VO 1 o i : : ; : ? ^ to g 10 O O oo 10 t^. '. t-- q O oo 2 10 00 t^ o 4- ro -4- M ^ ro : ' '. "2 ' t^ ro C o *? O MS: t^ oo o "* 8 : M ' : 4 4 \ ro ro O 00 I H d i $* N vo N t^ M O' N N in s. :-* % o : &H : bca : gi^ o : >H . C jp fl -rt . >| : ^(^o gS "p : .S>, >,S t^ ^Sa ^g MPL, g M > p o> iJ a ^ w W i | c2x | C aJ d o 2 3 **g S >,5^ fc ^gs - m > 3 ^ - 3 WCB i, East Galicia Pe- troleum West Galicia Pe- troleum i88 OIL ENGINES. TABLE IX. OIL FUEL. (B. REDWOOD.) Chemical Compo- Heating sition. Power. Locality. Fuel. Sp. Gr.at Actual Calcu- Car- Hy- dro- Oxy- Calori- metric lated (Ib. C. gen. (Ib. C. Heat Units?.) Units.) Russian. Petrol refuse o 028 87 I ., 2 Astatki o o 8il Qd I"* 06 2 IO ^J.O 1 1 626 Caucasian Heavy Crude 0.938 86.6 84.9 12.3 11.63 .1 4S8 10,800 10,328 11,200 " (Novorossisk) Pennsylvanian .... < 0.886 84.0 13.7 1 10 672 American < < 86. 894 13. IO7 10 912 i< Refined 8^.401 i4.2l6 O. 2Q^ II 04^ 9 6 3 Oil from Dandang, Leo Rembang, ) Java. f 0.923 10,831 Light Oil from Baku 0.884 ii 460 Oil from Western Galicia 0.88^ 10,231 " " Eastern " 0.870 10,005 ii K Parma 0.786 IO,12I " " Schwabweiler 0.861 10,458 INDEX. 189 INDEX. PAGE ABEL oil-tester 90 Actual horse-power 63 Air compressing, horse- power required 125 Air-compressor at differ- ent altitudes 131 Air-compressors 123 Air inlet choked 77 Air-inlet valve.. 12, 23, 39, 57, 61, 78, 145, 165, 1 68 Air-inlet valve, auto- matic 12, 77, 156 Air-pump 13 Air-receiver 177 Air suction, noise of 122 Air-suction pipe 78 Air- supply ( Campbell ) 151 Air-supply (Crossley) .... 149 Air-supply (Priestman).. .152 Asbestos 58 Assembling oil engines... 53 Atmospheric line 70, 71 BALANCE weights 30 Balancing crank-shaft.... 27 Balancing fly-wheel 30 PAGE Balancing formula 29 Bearings caps 55 Bearings, crank-shaft. 42, 158 Bearings, outside 161, 165 Bearings, pressure on. . .42, 43 Bearings, scraping in 54 Beau de Rochas Cycle, 15, 16, 76, 177 Belt centres 115 Belt, link 113, 115 Belt, loose 115 Belt, size of 116 Benzine i B. H. P., to calculate 65 Brake, attaching 64 Brake, horse-power 63, 64 CAMPBELL, governing,, 13, 151, 168 Campbell oil engine de- scribed 165 Campbell starting 150 Cams 37 Cams, setting 60 Circulating water-pipes... 97 Clerk, Dugeld 87 190 INDEX. PAGE Clutches, friction 137 Clutches, friction, advan- tages of 137 Clutches, friction, B and C type 138 Coal oil i Combustion, bad 89, 153 Combustion, complete 90 Compression (Diesel) . . .6, 25 Compression in crank- chamber. 172 Compression, increasing. .. 79 Compression, irregular... 19 Compression line 76, 78 Compression pressure 25 Connecting-rod bearings. . 56 Connecting-rods 30 Connecting-rods, diameter 33 Connecting-rods, phosphor bronze 31 Cooling surface 23 Cooling water 19, 183 Cooling water-tanks 96 Copper ring 58 Crank-pin 42, 168 Crank-pin dimensions .... 42 Crank-pin, size of 26 Crank -shaft 25 Crank-shaft, balancing. ... 27 Crank-shaft bearings. .42, 158 Crank-shaft, strength of . . 26 Crossley engine described. 161 Crossley governing. 164 Crossley measuring device. 161 Crossley starting 148 Cundall engine described. .165 PAGE Cycles, different, discussed 18 Cylinder clearance 23 Cylinder cover 23 Cylinder lubricating oil... 140 Cylinder lubricators 38 Cylinder, two or more parts 57 Cylinders, different types. 22 DENTON, Prof 181 Developed horse-power... 63 Diagram, analyzing 77 Diagram, good working. . 76 Diesel governing 180 Diesel heat balance 181 Diesel motor 6, 177 Diesel starting 177 Direct-connected engine and dynamo 117 Direction of rotation, re- versing 154 Distance-pieces 55 Draining, water 104 Dynamo fly-wheel 115 Dynamometer or brake 64 EFFECTIVE horse-power .... 63 Efficiencies, thermal, com- pared 87 Efficiency, increase of 83 Efficiency, mechanical. .51, 86 Efficiency, thermal 86 Electric igniter 5, 15, 152 Electric lighting plant, in- stallation of 113 Engine ( Campbell ) 165 INDEX. 191 PAGE Engine (Cundall) 165 Engine frame 42 Engine (Hornsby-Akroyd) 140 Engine (Mietz and Weiss) 170 Engine, portable 181 Engine (Priestman) 168 Engines (Crossley) 161 Engines driving dynamos, in Engines, electric lighting. . 46 Engines, knocking 159 Engines, regulation of 117 Engines, running, general remarks 153 Engines, running, light... 145 Erecting oil engines 53 Exhaust bends 41 Exhaust, choked 83 Exhaust gases 90, 153 Exhaust line 76, 83 Exhaust silencers 100 fcxhaust temperature no Exhaust valve 13 Exhaust valve, opening of. 76 Exhaust washer 101 Expansion line 76, 81 Explosion 20 Explosive mixture 10, 15 FILTER oil 49, 146, 160 Flashing point of oil I Flashing point to test 90 Flickering of incandescent lights 119 Fluctuation in speed 37 Fly-wheels 35, 119 Fly-wheels, energy of 53 PAGE Fly-wheels for dynamo.. 115 Fly-wheels, formula for. . . 37 Fly-wheels, keying on. ... 57 Fly-wheels, peripheral speed 36 Formulae 20, 21, 26, 29, 33, 37, 40, 86, 125 Foundations 113 Four-cycle 15 Frame, engine 42 Friction-clutches 137 Friction-clutches, advan- tages of 137 Friction-clutches, B and C type 138 Frost, provision for 99 Fuel consumption. See Tables. Fuel-consumption test.... 87 Fuel injection 9, 180 Fuel oil-tank 13, 49, 161 165, 167, 169, 170, 173, 177 GASES, exhaust 90 Gear, skew 43 Gear, spur 43, 160 Gear, starting 21 Governing (Campbell), 13, 151, 168 Governing (centrifugal), 15, 164, 165, 168 Governing (Crossley) 164 Governing devices 44 Governing (Diesel) 180 Governing (Mietz and Weiss) .......... 171 192 INDEX. PAGE Governing (Priestman), 15, 169 Governor, hit-and-miss type 48 Governor, hunting 148 Governor parts, renewing. 160 Governor, pendulum type.. 4-5 Governor, Porter type. ... 173 Gravitation (fuel) 12, 168 Gravitation system 96 HEAT, utilization of waste. 107 Heated air 1 1 Heat balance 87 Heat balance (Diesel) . . . 181 Heating lamp 8, n, 12 Heating lamp instructions. 141 Horizontal and vertical types 50 Hornsby-Akroyd, instruc- tions for running 140 Hornsby-Akroyd, method of vaporizing 9 Hornsby-Akroyd oil sup- ply 173 Horse-power 63, 66 ICE and refrigerating ma- chines 133 Igniter, electric 5, 15, 152 Igniter (Hornsby-Akroyd) 2 Igniters 2, 23 Igniters (flame) 2 Igniters, heating 61 Ignition 140 PAGE Ignition (electric) 2, 7 Ignition (high compres- sion) 2 Ignition (hot surface) 2, 7, IO Ignition (hot tube), 2, 7, n, 148, 151 Ignition line 76 Ignition line, late 80 Ignition line, too early... 79 Ignition, regulating 80 Ignition, retarding. ....... 81 Impulse on piston 17 Incandescent lights 116 Incandescent lights, flick- ering of 119 Indicated horse-power. ... 66 Indicator attaching to en- gine 71 Indicator cock 66 Indicator, Crosby 67 Indicator diagram 48, 75 Indicator diagram, light spring 88 Indicator, diagram meas- uring 73 Indicator in place 64 Indicator, left or right hand 70 Indicator reducing motion. 71 Indicator springs 69 Ingredients for founda- tions 113 Instructions for running Hornsby-Akroyd 140 Instructions for running oil engines 139 INDEX. 193 JUNK rings. PAGE : 55 KNOCKING in engine 159 LEAKAGE in crank-chamber 19 Leakage of piston-rings. 61, 78 Leakage of valves 78 Leakage of water into cyl- inder 63 Lights, incandescent 116 Line, atmospheric 70, 71 Line, compression 76, 78 Line, exhaust .76, 83 Line, expansion 76, 81 Link belt 113, 115 Loose belt .115 Lubricating cylinder oil ... 140 Lubricators, cylinder 38 Lubricators, sight feed. . . 38 MEASURING device (Cross- ley) 161 Mechanical efficiency. ..51, 86 M. E. P 21, 67, 81 M. E. P. gas and gasoline engines 22 M. E. P. regulated 47 Method of vaporizing (Crossley) n Method of vaporizing (Campbell) 12 Method of vaporizing (Hornsby-Akroyd) ... 9 Method of vaporizing (Priestman) 13 PAGE Method of governing (Campbell) 168 Method of governing (Diesel) 180 Method of governing (Mietz and Weiss) ... 171 Method of governing (Priestman) 169 Mietz and Weiss engine described 170 Mietz and Weiss engine governing 171 Mixture oil, vapor and air. 14 Motor, Diesel 6, 177 NORRIS, William 26 OIL cylinder, lubricating. .140 Oil engines, driving dy- namos in Oil engines, instructions for running 139 Oil filter 49, 146, 160 Oil inj ection 9 Oil inlet 12 Oil measurer (Crossley).. II Oil-pump 9, 143, 165 Oil-pump, testing 147 Oil supply (Campbell) ... 151 Oil supply (Crossley) .... 164 Oil supply (Diesel) 177 Oil supply (Hornsby-Ak- royd) 173 Oil supply, limiting 89 194 INDEX. PAGE Oil supply (Mietz and Weiss) 170 Oil-supply pipes... 57, 61, 146 Oil supply (Priestman) ... 15 Oil-supply pump 171 Oil-supplying apparatus... 51 Oil, viscosity of 93 Otto cycle 15, 76 Otto patent 19 PARAFFIN (Scotch) i Petroleum I Petroleum (crude) 2, 20 Petroleum. See Tables. Pipe, air-suction 78 Piston 33, 153 Piston, fitting 55 Piston lubrication, 50, 158, 170, 1 80 Piston-rings, 34, 55, 56, 154, 158, 159 Piston speed 34 Piston, taking out 158 Planimeters 72 Planimeters, directions for using 74 Plants, pumping 131 Portable engines i$i Portable engines, construc- tion of 182 Portable engines (Horns- by-Akroyd) 182 Port openings 39 Pressure of explosion 20 Pressure on bearings. ..42, 43 Priestman engine 168 PAGE Priestman, governing. . 15, 169 P'riestman, starting 152 Priming cup (Crossley) . . 148 Processes in cylinder 59 Producer gas plant 20 Products of combustion. . . 18 Pump, oil-supply 49 Pump, water-circulating. . 99 Pumping plants 131 Pumps, efficiency of 133 Pumps, horse-power re- quired 132 REFRIGERATING machines. ..133 Refrigerating machines, horse-power required.. 136 Refrigerating machines, rating of 133 Regulation of engines 117 Reversing direction of ro- tation 154 Rhumkorft" coil 5 Rings, junk 55 Rings, piston, 34, 55, 56, 154, 158, 159 Running oil engines 139 SALT WATER, cooling 100 Self-starter 105 Self-starter (Hornsby-Ak- royd) 105 Silencers, exhaust 100 Simplicity of construction. 21 Single cycle 16 Skew gear 43 Specific gravity I INDEX. 195 PAGE Speed counter (Hill) 85 Speed, regulation of 154 Sprayer (Priestman) 13 Spray holes 147 Spur gear 43, 160 Starting '. 1 1 Starting (Campbell type). .150 Starting (Crossley type) . .148 Starting (Diesel motor).. 177 Starting, difficulties of.6i, .143 Starting gear 21 Starting (Hornsby-Ak- royd) 142 Starting (Priestman type). 152 Starting valve 179 Straight line principle. . . .168 Suction line 76 TACHOMETERS 83 Tachometers, portable 84 Tank 49 Tank, fuel consumption. . 64 Tank, water 141 Temperature of cooling water. 81, 100 Temperature, exhaust . . . . 1 10 Testing compression 61 Testing flash-point 90 Testing fuel consumption. 87 Testing new engine'. 59 Testing, object of 59 Testing oil-pump 147 Testing sprayer 61 Testing water-jackets 63 Thermal efficiency. . . .86, 180 Two-cycle system.. 15, 44, 170 PAGE Two-cylinder engines 51 VALVE, air and exhaust, 39, 57, 145, 158, 177 Valve, back pressure 146 Valve by-pass 45, 173 Valve closing-springs 39 Valve exhaust opening. ... 60 Valve, lift of 78 Valve mechanisms 43 Valve, overflow, oil 146 Valve starting 179 Valves 21, 41 Valves and valve-boxes... 38 Vapor inlet-valve. .11, 12, 150 Vaporizer, advantages of . . 8 Vaporizer (Campbell) 5 Vaporizer (Crossley) . .11, 150 Vaporizer, difficulties of. . 9 Vaporizer heated by ex- haust 14 Vaporizer, heating. . . .61, 152 Vaporizer (Hornsby-Ak- royd) 9 Vaporizer (Priestman)... 13 Vaporizer 7 Vaporizer, to heat 141 Vaporizer valve-box 145 Vaporizer, water-jacketed. 141 Vertical engines 51 Vibrator 6 Viscosity of oil 93 WASHER, exhaust 101 Waste heat, utilization of. .107 Water-circulating pipes... 97 196 INDEX. PAGE Water-circulating pump. . . 99 Water cooling 183 Water draining 104 Water in exhaust-pipe 104 Water-jackets 57, 180 PAGE Water, salt, cooling 100 Water space 23 Water-tanks, capacity of . . 96 Water-tanks, cooling. .96, 141 Worm-gear 43, 160 LUNKENHEIMER OlL-MlXER OR GENERATOR VALVE. This oil-feeder, applicable alike to both kerosene and gasoline, is quite simple and readily attached to engine. It is automatic, and feeds the oil in a thoroughly atom- ized state, but does not "heat same to the vaporizing point. If the engine is to operate with gasoline, warm- ing the in-coming air is advisable. If kerosene or heavy oils are used, the mixer should be arranged so that the fresh air drawn in through opening C (see cuts) opens disc E. This allows oil to flow in through passage K, where, meeting the rapidly entering air, it is thoroughly broken up into a spray,, and passing on enters the heater or vaporizer, and from thence to cylinder. Disc E is closed by spring M, the seat being very wide, it covers passage-way K, automatically shutting off the oil. The regulation is adjusted by means of the needle- valve F and pointer G. The mixer, while one of the newest, seems to em- body every requirement of a device for this purpose, and could no doubt be profitably employed by many more builders of engines of this class. e Lunkenheimer Co. General Offices and Factory CINCINNATI, O., U. S. A. BRANCHES New York London 26 Cortlandt St. 35 Great Dover St. MANUFACTURE A COMPLETE LINE OF ACCESSORIES FOR Oil Engines Generator Valves Globe Angle and Cross, Stop and Needle Valves Check Valves Stop Cocks Water and Oil Gauges Cylinder Lubricators Drain Cocks Special Fittings Bearing Oilers, Single or Multiple Grease Cups, etc. Special Fittings made to order for Engine Builders. Sena for Complete Catalogue Lubrication Proper lubrication is one of the most vital points in the operation of any piece of machinery, and particu- larly so with the Gas or Oil Engine. There are special requirements to be considered, and too much care cannot be exercised in the selection of an oil to meet them. An oil which has been adapted and found sat- isfactory for other kinds of engines may not be at all suited for the Oil Engine. The action of heat on the lubricating oil must be taken into consideration, and the burning point of the oil be high enough to withstand the heat generated under the highest speed. The viscosity should be such that so great a reduction will not take place under heat as to impair the lubrication. Inasmuch as most animal oils contain matter which liberates injurious acids under the action of heat, it is essential that compounded oils be avoided as dangerous. The Columbia Lubricants Company have made a special study of the requirements of the Gas and Oil Engines and have been able to meet them in every detail. They have prepared a special oil which among other essential tests has a burning point of 525 degrees Fahrenheit. The use of this oil will insure perfect lubrication under all conditions and an economy in the amount used. For further information on this and other specially adapted oils, we invite correspondence. Columbia Lubricants Company 121 Maiden Lane - ' , ,--"' &(ew> York City OVER SIX THOUSAND IN ACTUAL OPERATION SIZES: 2 TO 50 BRAKE H. P. USED BY THE UNITED STATES, BRITISH, AND SEVEN OTHER GOVERN- MENTS NO ELECTRIC SPARK NO TUBE IGNITION ALWAYS SAFE AND RELIABLE STARTS WITH- OUT DIFFICULTY WORKS AUTOMATICALLY Sole ^Manufacturers in the United States The De La Vergne Refrigerating Machine Co., Foot East /38th Street, Ne