T J IRLF 315 GIFT Of Tentative Boiler Safety Orders Prepared by a Sub-Committee Representing Various Interests related to the Manufacture, Use and Inspection of Boilers at the request of the Industrial Accident Commission of the State of California For the Criticisms or Suggestions of Employers, Employees and Others Interested Due notice will be given of Public Hearings to be held for the consideration of these Tentative Safety Orders CALIFORNIA STATE PRINTING OFFICE 1916 - INDUSTRIAL ACCIDENT COMMISSION OF THE STATE OF CALIFORNIA JOHN R. BROWNELL, Superintendent of Safety. 525 Market Street, San Francisco 423 Union League Building, Los Angeles A. J. PILLSBURY. WILL J. FRENCH, MEYER LISSNER, ; Commissioners. FOREWORD. Sections 51 to 72, inclusive, of the Workmen's Compensation, Insurance and Safety Act, give the Industrial Accident Commission power to make and enforce safety orders, rules and regulations, to prescribe safety devices, and to fix safety standards. It also empow- ers the Commission to appoint advisors who shall, without com- pensation, assist the Commission in establishing standards of safety. The Commission may adopt and incorporate in its general orders such safety recommendations as it may receive from such advisors. The Commission, carrying out its plan of obtaining the best prac- tical ideas to incorporate in its Safety Orders, asked various interests to serve on sub-committees to draft Boiler Safety Orders. These sub-committees were named after consultation with the Gen- eral Rules Committees, which were organized in San Francisco and Los Angeles, and which assisted the Commission in the preparation of General Safety Orders which went into effect January 1, 1916. As with the General Rules Committees, one sub-committee on Boiler Orders met in San Francisco, the other meeting in Los Angeles. 36SG04 San Francisco Sub-Committee on Boiler Safety Orders. GEOKGE A. AEMES (Chairman), representing the Union Iron Works, as manu- facturers of Boilers. (FREDERICK BIRDSALL, Alternate to Mr. Armes.) E. R. KILLGORE, representing the Standard Oil Company, as users of Boilers. J. B. WARNER, representing the Hartford Steam Boiler Inspection and Insurance Company. D. P. DELURY, representing the Board of Public Works of San Francisco. M. J. McGuiRE, representing the Boilermakers and Shipfitters Union. P. L. ENNOR, representing the International Union of Steam and Operating Engineers, Local No. 64. (W. R. TOWNE, Alternate to Mr. Ennor), International Union of Steam and Operating Engineers, Local No. 64. CHAS. A. SMITH, representing the California Metal Trades Association. JOHN MITCHELL, representing the International Union of Steam and Operating Engineers, Local No. 507. R. L. HEMINGWAY, Safety Engineer, Industrial Accident Commission. JOHN R. BROWNELL (Secretary), Superintendent of Safety, Industrial Accident Commission. Los Angeles Sub-Committee on Boiler Safety Orders. FRED J. FISCHER (Chairman), representing the National Association of Steam Engineers No. 2. H. L. DOOLITTLE (Vice-Chairman), representing the Southern California Edison Company. J. J. MALONE, representing the Hartford Steam Boiler Inspection and Insurance Company. WILLIAM H. CARTER, Chief City Boiler and Elevator Inspector, representing the City of Los Angeles. S. M. WALKER, representing the Pioneer Boiler and Machine Works. J. L. GLENNON, representing the Fidelity and Casualty Company of New York. N. E. CARROLL, representing the Steam and Operating Engineers No. 1'2> E. C. JORDAN, representing the Firemen's Local No. 220. II. L. BOYD (Secretary), Safety Engineer, Industrial Accident Commission, CONTENTS. Page TENTATIVE BOILER SAFETY ORDERS vii-xiii INDEX TO TENTATIVE BIOLER SAFETY ORDERS xiv-xv A. S. M. E. BOILER CODE, WITH APPENDIX 1-114 INDEX TO A. S. M. E. CODE__ _ 117-147 TENTATIVE BOILER SAFETY ORDERS. Order 400. Inspection of steam boilers. (a) All steam boilers operated in the State of California, except those exempt by (6) of this Order, shall be subject to a regular internal and external inspection each year, if in service at any time during the current year, except that an interval of fourteen (14) months may be allowed when necessary. (&) Exemptions: The following boilers are exempt from inspec- tion by the Industrial Accident Commission : 1. Boilers under the jurisdiction of the United States. 2. Boilers of railroad locomotives used in interstate commerce and boilers under United States inspection. 3. Boilers used exclusively for agricultural purposes. 4. Boilers of eight (8) horsepower or less, on which the pres- sure does not exceed fifteen (15) pounds per square inch. 5. Automobile boilers and road motor vehicles. (c) Whoever owns or causes to be used a boiler subject to inspec- tion shall report the location of such boilers to the Industrial Acci- dent Commission of the State of California on January 1st, or within thirty (30) days thereafter, of each year. (d) The owner or user of a boiler or boilers herein required to be inspected shall, after fourteen (14) days' notice, prepare the boiler for internal inspection, or hydrostatic pressure test, if neces- sary. To prepare a boiler for internal inspection, the water shall be drawn off and the boiler thoroughly washed. All manhole and handhole covers, and wash-out plugs in boilers and water column connections shall be removed, and the furnace and combustion chamber thoroughly cooled and cleaned. The steam gage shall be removed for testing. (e) If it is found that steam or hot water is leaking into the boiler, the source of such leakage shall be disconnected and so drained as to cut out such steam or hot water from the boiler to be inspected. (/) If the boiler is jacketed so that the longitudinal seams of shells, drums or domes can not be seen, and if it can not otherwise be determined, enough of the jacketing, setting wall or other covering shall be removed so that the size and pitch of the rivets and such other data as may be necessary can be determined at first data inspection. TENTATIVE BOILER SAFETY ORDERS. (g) In preparing a boiler for hydrostatic test, the boiler shall be filled to the stop valve. If boiler to be tested is connected with other boilers that are under steam pressure, such connections shall be blanked off unless there be double stop valves on all connecting pipes, with an open drain between. Order 401. Insurance inspections. All boilers subject to periodic inspection of insurance companies authorized to insure boilers in the State of California shall be exempt from regular annual inspection by the Industrial Accident Commission on the following conditions : (a) The insurance companies' regulations shall conform with the herein orders. (&) The insurance companies' inspectors who inspect boilers operated in this State shall hold certificates of competency issued by the Industrial Accident Commission, as hereinafter provided. (c) Eeports of all inspections shall conform to the requirements of this Commission, and shall be made upon the forms provided. (d) A copy of all annual reports shall be forwarded to this Commission within twenty-one (21) days after the inspection is made, on the forms provided. (e) Insurance companies whose inspectors hold certificates of competency shall immediately report to this Commission the name of the owner or operator, and the location of every boiler on which insurance has been refused, cancelled or discontinued, giving the reasons therefor. Order 402. Special inspections. (a) Steam boilers within the regular corporate limits of counties and cities, which are regularly inspected by an authorized county or city inspector, and steam boilers operated or controlled by com- panies or corporations which receive regular annual inspections by an inspector employed by the said companies or corporations, shall be exempt from the regular annual inspections made by this Com- mission, on the following conditions : 1. The boilers shall be installed and equipped with the fittings necessary to safety as prescribed by these Orders. 2. The inspector or inspectors shall hold certificates of com- petency issued by the Industrial Accident Commission. 3. Reports of all inspections shall conform to the requirements of, and a copy of said reports shall be forwarded to this Commission within twenty-one (21) days after the inspec- tions are made, on the forms provided. TENTATIVE BOILER SAFETY" ORDERS. IX Order 403. Certificate of competency. (a) Certificates of competency shall be issued to persons who are employed as provided in Section (&), and who pass an exami- nation which shall be prescribed by the Industrial Accident Commission which shall determine the fitness and competency of candidates for such certificate of competency.* (6) Holders of certificates of competency shall be employed as inspectors only and shall comply with the herein Orders. Copies of their reports of inspections shall be forwarded to the Industrial Accident Commission of the State of California within twenty-one (21) days after each inspection. (c) A certificate of competency may be revoked for cause at any time, but the holder of such certificate of competency shall be entitled, upon demand, to a hearing before the Industrial Accident Commission before the revocation of the certificate of competency. (d) A certificate of competency issued to an employee of any county, city, corporation or company shall be annulled upon the termination of his employment by the said county, city, corporation or company by which he was employed at the time of the issuance of the certificate of competency. Such certificate of competency may, however, be renewed without a re-examination within a period of one year upon proof that the applicant has been re-engaged as a boiler inspector. 1. Any applicant who fails to pass the examination may apply for a re-examination at the end of ninety days. Pro- vided, however, that a person who has been refused a certificate of competency may appeal from such decision to the Industrial Accident Commission who shall grant a re-hearing. The applicant shall have the privilege of having one representative of the county, city, corpora- tion or company by whom he is or is to be employed, present during the hearing. Order 404. Annual inspection certificate. (a) A certificate of inspection upon the forms supplied by the Industrial Accident Commission shall be issued by the inspector in the employ of the county, city, corporation, or company, stating the pressure allowed for one year after an inspection has been made. This certificate shall be kept conspicuously posted under glass in the engine or boiler room, and shall at all times be available when * Candidates will be examined as to their knowledge of the construction, installation, operation, maintenance and repair of steam boilers, and of the rules governing boilers in California. X TENTATIVE BOILER SAFETY ORDERS. called for by a deputy of this Commission, or by an inspector holding a certificate of competency. (6) The pressure allowed as stated in the certificate of inspec- tion shall not be in excess of that determined by the Orders for boilers installed prior to January 1, 1917. Order 405. Stamps and numbers on boilers. (a) The owner or user of a steam boiler shall number each boiler in some convenient and permanent manner. (6) Boilers installed after January 1, 1917, shall be stamped by the builder with a serial number, date of manufacture and his name, in accordance with the herein Orders. (c) Boilers installed after January 1, 1917, shall conform with these Orders, be inspected before installed, and stamped by an inspector holding a certificate of competency. Order 406. Special type of boilers. (a) Builders of special types of boilers subject to inspection shall forward to the Industrial Accident Commission blue prints and specifications of the type for approval. Order 407. Safety regulations. (a) No boiler shall be operated at a pressure in excess of the safe working pressure allowed by the annual inspection certificate, which pressure is to be ascertained by means of these Orders. Order 408. (a) Boilers of eight (8) horsepower or less, on which the pres- sure does not exceed fifteen (15) pounds per square inch, which are exempt from inspection, shall be fitted with such appliances as to insure safety as herein prescribed. Order 409. (a) Any boiler in this State at the time these Orders take effect which does not conform to the herein Orders, may be operated, if found safe, after a thorough internal and external inspection, and a hydrostatic pressure test, if necessary. (&) No boiler shall be installed in the State of California after these Orders take effect, which was not stamped when built by the manufacturer with the American Society of Mechanical Engineers' Boiler Code Stamp, except after a joint inspection by the Indus- trial Accident Commission and another inspector holding a certifi- TENTATIVE BOILER SAFETY ORDERS. XI cate of competency. The lowest Factor of Safety on boilers of this kind shall be six (6). Order 410. (a) Steam boilers shall be equipped with such appliances as will insure safety of operation as herein ordered. Order 411. (a) No person shall remove or tamper with any safety appliance prescribed by the herein Orders, and no person shall in any man- ner load the safety valve to greater pressure than that allowed by the certificate of inspection. Order 412. (a) In case a defect affecting the safety of a steam boiler is discovered, the owner or user of the boiler shall immediately notify the inspector issuing the certificate of inspection, but if said boiler be not subject to inspection, the owner or user shall in that case report the defect to the Industrial Accident Commission. Order 413. (a) All patches on a boiler shell or drum which exceed twenty- four (24) inches in length, measured on a line parallel to the longitudinal seam, and between the center lines of the extreme rivet holes, shall be calculated for safe working pressure from said patch seam, the efficiency of which shall be determined in the usual manner. The efficiency of the patch seam may then be increased by multi- plying said efficiency by a factor which is determined by the angularity of the inclined patch seam to the girth seam, according to the following table : Angle Factor Angle Factor 30 1.51 50 1.20 35 1.42 55 1.15 40 1.34 60 1.11 45 1.27 65 1.08 Order 414. (a) No cast iron hot water heating boiler shall carry a greater pressure, static or from supply main, than that named in the guar- Xll TENTATIVE BOILER SAFETY ORDERS. antee of the manufacturer, and in no case shall the pressure exceed thirty (30) pounds per square inch. Order 415. (a) Where it is found impossible to definitely determine the age of a boiler of lap seam construction, the factor of safety shall be not less than five and one-half (5J). (6) No pressure on a boiler of lap seam construction shall exceed one hundred and sixty-five (165) pounds per square inch. Order 416. (a) The use of plug cocks so constructed that there is no gland or yoke to hold the plug in place will not be allowed. If yokes or glands are of the open hole slot type at both ends, they shall have said slots effectively closed. Order 417. (a) Where boiler settings are so designed that gas can accumu- late to a dangerous extent, provision must be made for venting said gas pockets. (6) All dampers used in connection with oil burning furnaces under steam boilers shall be made with, or have suitable openings therein to vent the furnace from an accumulation of gas. Order 418. (a) If there are valves in the connections between water column and boiler, at least one steam gage shall be connected directly to steam space of boiler, with but one cock between said gage and boiler. Order 419. (a) In computing the horsepower for various types of boilers, the following table shall be used : Type of boiler Cylindrical Flue Firebox tubular Return tubular . Vertical Water tube _. Water heating surface for 1 horsepower. Square feet 10 12 is 15 10 TENTATIVE BOILER SAFETY ORDERS. Xlll Order 420. (a) The Boiler Code, Edition of 1914, with Index, of the Ameri- can Society of Mechanical Engineers, as copyrighted in 1915, is made a part of these Orders with the following changes: To paragraph 379, page 89; paragraph 380, page 89; paragraph 388, page 90; paragraph 396, page 92; paragraph 398, page 92; para- graph 404, page 93; paragraph 406, page 93; paragraph 408, page 93 ; paragraph 427, page 109, Code Appendix ; paragraph 428, page 113, Code Appendix, of said Boiler Code, which is appended hereto with the said changes, all of which said changes refer to Existing Installations. Order 421. Steam heating boilers [existing and new installations] . Fittings and Appliances. (a) There shall be a stop valve on each steam outlet from the boiler, except a safety valve connection. (6) When a damper regulator is used, it shall be connected to the steam space of the boiler and there shall be a stop valve or stop cock in the connecting pipe. (c) The main return pipe to a heating boiler (gravity return system) shall have a check valve and also a stop valve between the said check valve and the boiler. When there are two connected boilers with a gravity return system, one check valve may be placed on the main return pipe and a stop valve on the branch pipe to each boiler. (d) Each boiler shall have a feed pipe fitted with a check valve and also a stop valve between the check valve and the boiler, the feed water to discharge below the lowest safe water line. Means must be provided for feeding a boiler against the maxi- mum pressure allowed on the boiler. XIV INDEX. INDEX TO TENTATIVE BOILER SAFETY ORDERS. Page Order Subdi- vision Age of boiler unknown xii 415 a Appliances xi 410 a A. S. M. E. Boiler Code xiii 420 a Blow offs. Plug cocks not allowed xii 416 a Boiler Code of A. S. M. E xiii 420 a Boilers in State when these Orders take effect x 409 a Boilers not bearing A. S. M. E. Code Stamp x 409 b Boilers of lap construction, 165 limit pressure xii 415 b Builder's serial number x 405 b Boilers, special types of x 406 a Boilers, steam heating xiii 421 Boilers, to be numbered x 405 a Certificate, annual inspection ix 404 Certificate, annual inspection, posted under glass ix 404 a Covering, insulating, to be removed vii 400 f Certificates of competency, annullment of ix 403 d Certificates of competency, examination for ix 403 a Certificates of competency, holders ix 403 b Certificates of competency. Insurance inspectors viii 401 b Certificates of competency, renewal of ix 403 d Damper regulator, valve or cock in xiii 421 b Dampers to be vented xii 417 b Defects, serious to be reported xi 412 a Examination for certificate of competency ix 403 d Exemptions from annual inspection vii 400 b Exemptions to have safety appliances x 408 a Exemptions to have safety appliances by Industrial Acci- dent Commission vii 402 a Feed pipe, stop valve and check valve in xiii 421 d Gage, steam, removal of vii 400 d Gage, connected to steam space . xii 418 a Gas pockets in flue or setting xii 417 a Gravity returns, stop valve and check valve in xiii 421 c Heating boilers, hot water xi 414 a Horsepower, ratio of heating surface to xii 419 a Hydrostatic, preparation for test vii 400 d-g Inspection, insurance viii 401 Inspection, internal, external vii 400 a Inspection, leaks to be stopped vii 400 e Inspection, notice of annual vii 400 d Inspection, preparation for annual vii 400 d Interval fourteen months vii 400 a Insurance, refused, cancelled or discontinued viii 401 e INDEX. XV Page Order Subdi- vision Inspections, special viii 402 Insurance inspectors, annual reports viii 401 d Insurance inspectors, reports to conform viii 401 c Insurance regulations to conform viii 401 a Jacketing to be removed vii 400 f Patches xi 413 a Pressure allowed x 404 b Report, annual, of location vii 400 c Safety regulations x 407 Safe working pressure x 407 a Safety valves, tampering or removing xi 411 a Valves, double stop on connecting pipes viii 400 g Valves, stop on steam pipes xiii 421 a THE AMERICAN SOCIETY' OF* ENGINEERS REPORT OF THE COMMITTEE TO FORMULATE STANDARD SPECIFICATIONS FOR THE CONSTRUCTION OF STEAM BOILERS AND OTHER PRESSURE VESSELS AND FOR THEIR CARE IN SERVICE KNOWN AS THE BOILER CODE COMMITTEE RULES FOR THE CONSTRUCTION OF STATIONARY BOILERS AND Ff)R ALLOWABLE WORKING PRESSURES Edition of 1914 with Index Copyright, 1915, by THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS To THE COUNCIL OF THE AMEEICAN SOCIETY OF MECHANICAL ENGINEERS Gentlemen: Your Committee appointed September 15th, 1911 to "Formulate .Standard .Specifications for the Construction of Steam Boilers and Other Pressure Vessels and for Care of .Same in Service" respectfully submits its final report on Eules for the construction and allowable working pressures of stationary boilers, which forms a por- tion of the. task assigned to it. The primary object of these Eules is to secure safe boilers. The interests of boiler users and manufacturers have been carefully con- sidered and the requirements made such that they will not entail undue hardship by departing too widely from present practice. Your Committee recommends that you appoint a permanent com- mittee to make such revisions as may be found desirable in these Rules, and to modify them as the state of the art advances, and that such committee should hold meetings at least once in two years at which all interested parties may be heard. Yours truly, JOHN A. STEVENS, Chairman WM. H. BOEHM EOLLA C. CARPENTER EICHAED HAMMON-D COMMITTEE CHAS. L. HUSTON EDWARD F. MILLER H. C. MEINHOLTZ* E. I). MEIER* Deceased* Submitted to the Council of THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS, Feb- ruary 13, 1915. Your Committee secured the assistance of the following Engi- neers as an Advisory Committee, representing various phases of the design, installation and operation of boilers and the Rules were un- animously approved by them. F. II. CLARK, Railroad Sub-Committee, The American Society of Mechanical Engineers. F. W. DEAN, Consulting Engineers. THOS. E. DURBAN, Boiler Manufacturers' Association, Uniform Specifica- tions Committee, for all types of boilers. CARL FERRARI, National Tubular Boiler Manufacturers' Association. ELBERT C. FISHER, Scotch marine and other types of boilers. ARTHUR M. GREENE, JR., Engineering Education. CHAS. E. GORTON, Steel heating boilers. A. L. HUMPHREY, Eailroad Sub-Committee, The American Society of Me- chanical Engineers. D. S. JACOBUS, Water-tube boilers. S. F. JETER, Boiler insurance. WM. F. KIESEL, JR., Eailroad Sub-Committee, The American Society of Me- chanical Engineers. W. F. MACGREGOR, National Association of Thresher Manufacturers. M. F. MOORE, Steel heating boilers. I. E. MOULTROP, Boiler users. RICHARD D. REED, National Boiler & Radiator Manufacturers' Association. H. G. STOTT, Boiler users. H. H. VAUGHAN, Railroad Sub-Committee, ihe American Society of Me- chanical Engineers. C. W. OBERT, Secretary to Committee. CONTENTS Part I. New Installations PAGES Section 1. Power Boilers 7-80 Section 2. Heating Boilers 81-87 Part II. Existing Installations ........... 89-93 Appendix 95-114 Index . 115-147 RULES FOR THE CONSTRUCTION OF STATIONARY BOILERS AND FOR ALLOWABLE WORKING PRESSURES The Rules are divided into two parts: f Section I, Power Boilers. PART I applies to new installations. ) | Section II, Heating Boilers. PART II applies to existing installations. PART I NEW INSTALLATIONS SECTION I POWER BOILERS ,SELECTION OF MATERIALS 1 Specifications are given in these Eules for the important ma- terials used in the construction of boilers, and where given, the ma- terials shall conform thereto. 2 Steel plates for any part of a boiler when exposed to the fire or products of combustion, and under pressure, shall be of firebox quality as designated in the Specifications for Boiler Plate Steel. 3 Steel plates for any part of a boiler, where firebox quality is not specified, when under pressure, shall be of firebox or flange quality as designated in the Specifications for Boiler Plate 'Steel. 4 Braces when welded, shall be of wrought-iron of the quality designated in the Specifications for Eefined Wrought-Iron Bars. 5 Manhole and handhole covers and other parts subjected to pres- sure and braces and lugs, when made of steel plate, shall be of firebox or flange quality as designated in the Specifications for Boiler Plate Steel. 6 Steel bars for braces and for other boiler parts, except as other- wise specified herein, shall be of the quality designated in the Specifi- cations for Steel Bars. 7 iStaybolts shall be of iron or steel of the quality designated in the Specifications for Staybolt Iron or in the .Specifications for Stay- bolt Steel. 8 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. 8 Rivets shall be of steel or iron of the quality designated in the Specifications for Boiler Rivet Steel or in the Specifications for Boiler Rivet Iron. 9 Cross pipes connecting the steam and water drums of water- tube boilers, headers and cross boxes and all pressure parts of the boiler proper over 2-in. pipe size, or equivalent cross-sectional area, shall be of wrought steel, or cast steel of Class B grade, as designated in the Specifications for Steel Castings, when the maximum allowable work- ing pressure exceeds 160 Ib. per sq. in. 10 Mud drums of boilers used for other than heating purposes shall be of wrought steel, or cast steel of Class B grade, as designated in the Specifications for 'Steel Castings. 11 Pressure parts of superheaters, separately fired or attached to stationary boilers, unless of the locomotive type, shall be of wrought steel, or cast steel of Class B grade, as designated in the Specifications for Steel Castings. 12 Cast iron shall not be used for boiler and superheater mount- ings, such as nozzles, connecting pipes, fittings, valves and their bon- nets, for steam temperatures of over 450 deg. fahr. 13 Water-leg and door-frame rings of vertical fire-tube boilers 36 in. or over in diameter, and of locomotive and other type boilers, shall be of wrought iron or steel, or cast steel of Class B grade, as designated in the Specifications for Steel Castings. The G or other flanged construction may be used as a substitute in any case. ULTIMATE STRENGTH OF MATERIAL USED IN COMPUTING JOINTS 14 Tensile Strength of Steel Plate. The tensile strength used in the computations for steel plates shall be that stamped on the plates as herein provided, which is the minimum of the stipulated range, or 55,000 Ibs. per sq. in. for all steel plates, except for special grades having a lower tensile strength. 15 Crushing Strength of Steel Plate. The resistance to crush- ing of steel plate shall be taken at 95,000 Ib. per sq. in. of cross-sec- tional area. 16 Strength of Rivets in Shear. In computing the ultimate NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS strength of rivets in shear, the following values in pounds per square inch of the cross-sectional area of the rivet shank shall be used: Iron rivets in single shear ........................................ 38,000 Iron rivets in double shear ................. . ............... ...... 76,000 Steel rivets in single shear ....................................... 44,000 Steel rivets in double shear ....................................... 88,000 The cross-sectional area used in the computations shall be that of the rivet shank after driving. MINIMUM THICKNESSES OF PLATES AND TUBES 17 Thickness of Plates. The minimum thickness of any boiler plate under pressure shall be % in. 18 The minimum thicknesses of shell plates, and dome plates after flanin shall be as follows: 36 In. or Under WHEN THE DIAMETER OF SHELL is Over 36 In. to 54 In. Over 54 In. to 72 In. Over 72 In. 19 The minimum thicknesses of butt straps shall be as given in Table 1. TABLE 1 MINIMUM THICKNESSES OF BUTT STRAPS Thickness of Minimum Thickness Thickness of Minimum Thickness Shell Plates, of Butt Straps, Shell Plates, of Butt Straps, In. In. In. In. K K H A * tt A A U H H H K W H A K H H A i % iH % * llf IK H 20 The minimum thicknesses of tube sheets for horizontal return tubular boilers, shall be as follows: WHEN THE DIAMETER OF TUBE SHEET is 42 In. or Under Over 42 In. to 54 In. Over 54 In. to 72 In. Over 72 In. % in. /g in. V 2 in. A in. 10 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. 21 Tubes for Water-Tube Boilers. The minimum thicknesses of tubes used in water-tube boilers measured by Birmingham wire gage, for maximum allowable working pressures not exceeding 165 Ib. per sq. in., shall be as follows : Diameters less than 3 in No. 12 B.W.G. Diameter 3 in. or over, but less than 4 in No. 11 B.W.G. Diameter 4 in. or over, but less than 5 in No. 10 B.W.G. Diameter 5 in No. 9 B.W.G. The above thicknesses shall be increased for maximum allowable working pressures higher than 1,65 Ib. per sq. in. as follows : Over 165 Ib. but not exceeding 235 Ib 1 gage Over 235 Ib. but not exceeding 285 Ib 2 gages Over 285 Ib. but not exceeding 400 Ib 3 gages Tubes over 4-in. diameter shall not be used for maximum allowable working pressures above 285 Ib. per sq. in. 22 Tubes for Fire-Tube Boilers. The minimum thicknesses of tubes used in fire tube boilers measured by Birmingham wire gage, for maximum allowable working pressures not exceeding 175 Ib. per sq. in., shall be as follows : Diameters less than 2V 2 in No. 13 B.W.G. Diameter 2% in. or over, but less than S 1 ^ in No. 12 B.W.G. Diameter 3*4 in. or over, but less than 4 in No. 11 B.W.G. Diameter 4 in. or over, but less than 5 in No. 10 B.W.G. Diameter 5 in No. 9 B.W.G. For higher maximum allowable working pressures than given above the thicknesses shall be increased one gage. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 11 SPECIFICATIONS FOR BOILER PLATE STEEL THESE SPECIFICATIONS 1 ARE SIMILAR TO THOSE OF THE AMER- ICAN SOCIETY FOR TESTING MATERIALS, SERIAL DESIGNATION A 30-14. 23 Grades. These specifications cover two grades of steel for boilers, namely : FLANGE and FIREBOX. I MANUFACTURE 24 Process. The steel shall be made by the open-hearth process. II CHEMICAL PROPERTIES AND TESTS 25 Chemical Composition. The steel shall conform to the fol- lowing requirements as to chemical composition : FLANGE FIREBOX Carbon Plates % in. thick and under. . 0.12 0.25 per cent Plates over % in. thick 0.120.30 percent Manganese 0.30 0.60 per cent 0.30 0.50 per cent Acid. . . Not over 0.05 per cent Not over 0.04 per cent Phosphorus | Bagic Not over 0.04 per cent Not over 0.035 per cent Sulphur Not over 0.05 per cent Not over 0.04 per cent Copper Not over O.C5 per cent 26 Ladle Analyses. An analysis shall be made by the manu- facturer from a test ingot taken during the pouring of each melt, a copy of which shall be given to the purchaser or his representative. This analysis shall conform to the requirements specified in Par. 25. 27 Check Analyses. Analyses may be made by the purchaser from a broken tension test specimen representing each plate as rolled, which shall conform to the requirements specified in Par. 25. 1 Approved and recommended in its modified form, October 9, 1914, by the Association of American Steel Manufacturers, the American Boiler Manu- facturers' Association, the National Tubular Boiler Manufacturers' Associa- tion, the National Association of Thresher Manufacturers and the representa- tives present of leading Water Tube Boiler Manufacturers, with whom the Boiler Code Committee was in conference on September 16, 1914, and by whom further modifications were afterwards offered. 12 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. Ill PHYSICAL PROPERTIES AND TESTS 28 Tension Tests, a The material shall conform to the follow- ing requirements as to tensile properties : FLANGE FIREBOX Tensile strength, Ib. per sq. in 55,000 65,000 55,000 63,000 Yield point, min., Ib. per sq. in 0.5 tens. str. 0.5 tens. str. Elongation in 8-in., min., per cent (See Par. 29) 1,500,000 1,500,000 Tens. str. Tens. str. 1} If desired steel of lower tensile strength than the above may be used in an entire boiler, or part thereof, the desired tensile limits to be specified, having a range of 10,000 Ib. per sq. in. for flange or 8000 Ib. per sq. in. for firebox, the steel to conform in all respects to the other corresponding requirements herein specified, and to be stamped with the minimum tensile strength of the stipulated range. c The yield point shall be determined by the drop of the beam of the testing machine. 29 Modifications in Elongation, a For material over % in. in thickness, a deduction of 0.5 from the percentages of elongation specified in Par. 28a, shall be made for each increase of % in. in thickness above % in., to a minimum of 20 per cent. I) For material % in. or under in thickness, the elongation shall be measured on a gage length of 24 times the thickness of the specimen. 30 Bend Tests, a Cold-It end Tests The test specimen shall bend cold through 180 deg. without cracking on the outside of the bent portion, as follows : For material 1 in. or under in thickness, flat on itself; and for material over 1 in. in thickness, around a pin the diameter of which is equal to the thickness of the specimen. 1) Quench-bend Tests The test specimen, when heated to a light cherry red as seen in the dark (not less than 1200 deg. fahr.), and quenched at once in water the temperature of which is between 80 deg. and 90 deg. fahr., shall bend through 180 deg. without cracking on the outside of the bent portion, as follows : For material 1 in. or under in thickness, flat on itself; and for material over 1 in. in thickness, around a pin the diameter of which is equal to the thickness of the specimen. 31 Homogeneity Tests. For firebox steel, a sample taken from a broken tension test specimen shall not show any single seam or cavity more than 14 i n - l n g? i n either of the three fractures obtained in the test for homogeneity, which shall be made as follows : NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 13 The specimen shall be either nicked with a chisel or grooved on a machine,, transversely, about 1/16 in. deep, in three places about 2 in. apart. The first groove shall be made 2 in. from the square end ; each succeeding groove shall be made on the opposite side from the preceding one. The specimen shall then be firmly held in a vise, with the first groove about % in. above the jaws, and the projecting end broken off by light blows of a hammer, the bending being away from the groove. The specimen shall be broken at the other two grooves in the same manner. The object of this test is to open and render visible to the eye any seams due to failure to weld or to interposed foreign matter, or any cavities due to gas bubbles in the ingot. One side of each fracture shall be examined and the length of the seams and cavities determined, a pocket lens being used if necessary. 32 Test Specimens. Tension and bend test specimens shall be taken from the finished rolled material. They shall be of the full > L-; Parallel Section. --*J Y< ----------- " ----- nofless thand u FIG. 1 STANDARD FORM OF TEST SPECIMEN REQUIRED FOR ALL TENSION TESTS OF PLATE MATERIAL thickness of material as rolled, and shall be machined to the form and dimensions shown in Fig. 1 ; except that bend test specimens may be machined with both edges parallel. 33 Number of Tests, a One tension, one cold-bend, and one quench-bend test shall be made from each plate as rolled. ~b If any test specimen shows defective machining or develops flaws, it may be discarded and another specimen substituted. c If the percentage of elongation of any tension test specimen is less than that specified in Pars. 28 and 29, and any part of the fracture is outside the middle third of the gaged length, as indicated by the scribe scratches marked on the specimen before testing, a retest shall be allowed. IV PERMISSIBLE VARIATION IN GAGE 34 Permissible Variation. The thickness of each plate shall not vary under the gage specified more than 0.01 in. The overweight 14 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. limits are considered a matter of contract between the steel manu- facturer and the boiler builder. V FINISH 35 Finish. The finished material shall be free from injurious defects and shall have a workmanlike finish. VI MARKING 36 Marking, a Each shell plate shall be legibly stamped by the manufacturer with the melt or slab number, name of manu- facturer, grade and the minimum tensile strength of the stipulated range as specified in Par. 28, in three places, two of which shall be located at diagonal corners about 12 in. from the edge and one about the center of the plate, or at a point selected and designated by the purchaser so that the stamp shall be plainly visible when the boiler is completed. ~b Each head shall be legibly stamped by the manufacturer in two places, about 12 in. from the edge, with the melt or slab number, name of manufacturer, grade, and the minimum tensile strength of the stipulated range as specified in Par. 28, in such manner that the stamp is plainly visible when the boiler is completed. c Each .butt strap shall be legibly stamped by the manufacturer in two places on the center line about 12 in. from the ends with the melt or slab number, name of manufacturer, grade, and the minimum tensile strength of the stipulated range as specified in Par. ,28. d The melt or slab number shall be legibly stamped on each test specimen. YIT INSPECTION" AND REJECTION 37 Inspection. The inspector representing the purchaser shall have free entry, at all times while work on the contract of the pur- chaser is being performed, to all parts of the manufacturer's works which concern the manufacture of the material ordered. The manu- facturer shall afford the inspector, free of cost, all reasonable facilities to satisfy him that the material is being furnished in accordance with these specifications. All tests (except check analyses) and inspection shall be made at the place of manufacture prior to shipment, unless otherwise specified, and shall be so conducted as not to interfere un- necessarily with the operation of the works. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 15 38 Rejection, a Unless otherwise specified, any rejection based on tests made in accordance with Par. ,27 shall be reported within five working days from the receipt of samples. b Material which shows injurious defects subsequent to its ac- ceptance at the manufacturer's works will be rejected, and the manu- facturer shall be notified. 39 Rehearing. Samples tested in accordance with Par. 27, which represent rejected material, shall be preserved for two weeks from the date of the test report. In case of dissatisfaction with the results of the tests, the manufacturer may make claim for a rehearing within that time. SPECIFICATIONS FOR BOILER RIVET STEEL THESE SPECIFICATIONS ARE SUBSTANTIALLY THE SAME AS THOSE OF THE AMERICAN SOCIETY FOR TESTING MATERIALS, SERIAL DESIG- NATION A 31-14. A REQUIREMENTS FOR ROLLED BARS I MANUFACTURE 40 Process. The steel shall be made by the open-hearth process. II CHEMICAL PROPERTIES AND TESTS 41 Chemical Composition. The steel shall conform to the fol- lowing requirements as to chemical composition : Manganese 0.30-0.50 per cent Phosphorus not over 0.04 per cent Sulphur not over 0.045 per cent 42 Ladle Analyses. An analysis to determine the percentages of carbon, manganese, phosphorus and sulphur shall be made by the manufacturer from a test ingot taken during the pouring of each melt, a copy of which shall be given to the purchaser or his representative. This analysis shall conform to the requirements specified in Par. 41. 43 Check Analyses. Analyses may be made by the purchaser from finished bars, representing each melt, which shall conform to the requirements specified in Par. 41. 16 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. Ill PHYSICAL PROPERTIES AND TESTS 44 Tension Tests, a The bars shall conform to the following requirements as to tensile properties : Tensile strength, Ib. per sq. in 45,000-55,000 Yield point, min., Ib. per sq. in 0.5 tens. str. Elongation in 8 in., min., per cent 1,500,00 but need not exceed 30 per cent. Tens. str. b The yield point shall be determined by the drop of the beam of the testing machine. 45 Send Tests, a Cold-bend Tests The test specimen shall bend cold through 180 deg. flat on itself without cracking on the out- side of the bent portion. b Quench-bend Tests The test specimen, when heated to a light- cherry red as seen in the dark (not less than 1200 deg. fahr.), and quenched at once in water the temperature of which is between 80 deg. and 90 deg. fahr., shall bend through 180 deg. flat on itself without cracking on the outside of the bent portion. 46 Test Specimens. Tension and bend test specimens shall be of the full-size section of bars as rolled. 47 Number of Tests, a Two tension, two cold-bend, and two quench-bend tests shall be made from each melt, each of which shall conform to the requirements specified. b If any test specimen develops flaws, it may be discarded and another specimen substituted. c If the percentage of elongation of any tension test specimen is less than that specified in Par. 44 and any part of the fracture is outside the middle third of the gaged length, as indicated by scribe scratches marked on the specimen before testing, a retest shall be allowed. 48 Permissible Variations in Gage. The gage of each bar shall not vary more than 0.01 in. from that specified. V WORKMANSHIP AND FINISH 49 Workmanship. The finished bars shall be circular within 0.01 in. 50 Finish. The finished bars shall be free from injurious de- fects and shall have a workmanlike finish. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 17 VI MASKING 51 Marking. Eivet bars shall, when loaded for shipment, be properly separated and marked with the name or brand of the manu- facturer and the melt number for identification. The melt number shall be legibly marked on each test specimen. VII INSPECTION AND REJECTION 52 Inspection. The inspector representing the purchaser shall have free entry, at all times while work on the contract of the pur- chaser is being performed, to all parts of the manufacturer's works which concern the manufacture of the bars ordered. The manu- facturer shall afford the inspector, free of cost, all reasonable facilities to satisfy him that the bars are being furnished in accordance with these specifications. All tests (except check analyses) and inspection shall be made at the place of manufacture prior to shipment, unless otherwise specified, and shall be so conducted as not to interfere un- necessarily with the operation of the works. 53 Rejection, a Unless otherwise specified, any rejection based on tests made in accordance with Par. 43 shall be reported within five working days from the receipt of samples. b Bars which show injurious defects subsequent to their ac- ceptance at the manufacturer's works will be rejected, and the manu- facturer shall be notified. 51 Rehearing. .Samples tested in accordance with Par. 43, which represent rejected bars, shall be preserved for two weeks frm the date of the test report. In case of dissatisfaction with the results of the tests, the manufacturer may make claim for a rehearing within that time. B REQUIREMENTS FOR RIVETS I PHYSICAL PROPERTIES AND TESTS 55 Tension Tests. The rivets, when tested, shall conform to the requirements as to tensile properties specified in Par. 44, except that the elongation shall be measured on a gaged length not less than four times the diameter of the rivet. 56 Bend Tests. The rivet shank shall bend cold through 180 cleg, flat on itself, as shown in Fig. 2, without cracking on the outside cf the bent portion. 18 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. 57 Flattening Tests. The rivet head shall flatten, while hot, to a diameter %y 2 times the diameter of the shank, as shown in Fig. 3, without cracking at the edges. 58 Number of Tests, a When specified, one tension test shall be made from each size in each lot of rivets offered for inspection. b Three bend and three flattening tests shall be made from each size in each lot of rivets offered for inspection, each of which shall con- form to the requirements specified. II WORKMANSHIP AND FINISH 59 Workmanship. The rivets shall be true to form, concentric, and shall be made in a workmanlike manner. 60 Finish. The finished rivets shall be free from injurious de- fects. J FIG. 2 THE BEND TEST FOR ElVETS FIG. 3 THE FLAT- TENING TEST FOR ElVETS III INSPECTION AND REJECTION 61 Inspection. The inspector representing the purchaser shall have free entry, at all times while work on the contract of the pur- chaser is being performed, to all parts of the manufacturer's works which concern the manufacture of the rivets ordered. The manu- facturer shall afford the inspector, free of cost, all reasonable facilities to satisfy him that the rivets are being furnished in accordance with these specifications. All tests and inspection shall be made at the place of manufacture prior to shipment, unless otherwise specified, and shall be so conducted as not to interfere unnecessarily with the operation of the works. 62 Rejection. Rivets which show injurious defects subsequent to their acceptance at the manufacturer's works will be rejected, and the manufacturer shall be notified. NEW INSTALLATIONS, PAET I, SECTION I, TOWER BOILERS 19 SPECIFICATIONS FOR STAY BOLT STEEL REQUIREMENTS FOR ROLLED BARS 63 Steel for staybolts shall conform to the requirements for Boiler Rivet Steel specified in Pars. 40 to 62, except that the tensile properties shall be as follows : Tensile strength, Ib. per sq. in 50,000-60,000 Yield point, min., Ib. per sq. in 0.5 tens. str. 1,500,000 Elongation in 8 in., min. ; per cent Tens. str. Also with the exception that the permissible variations in gage shall be as follows : Permissible Variations in Gage. The bars shall be truly round within 0.01 in. and shall not vary more than 0.005 in. above, or more than 0.01 in. below the specified size. SPECIFICATIONS FOR STEEL BARS THESE SPECIFICATIONS ARE ABSTRACTED FROM THOSE FOR STEEE FOR BRIDGES OF THE AMERICAN SOCIETY FOR TESTING MATERIALS, SERIAL DESIGNATION A 7-14. I MANUFACTURE 64 Process. The steel shall be made by the open-hearth process. II CHEMICAL PROPERTIES AND TESTS 65 Chemical Composition. The steel shall conform to the fol- lowing requirements as to chemical composition: Acid not over 0.06 per cent Basic not over 0.04 per cent Sulphur not over 0.05 per cent 66 Ladle Analysis. An analysis to determine the percentages of carbon, manganese, phosphorus and sulphur shall be made by the manufacturer from a test ingot taken during the pouring of each melt, a copy of which shall be given to the purchaser or his representa- tive. This analysis shall conform to the requirements specified in Par. 65. 20 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. Ill PHYSICAL PROPERTIES AND TESTS 67 Tension Tests, a The material shall conform to the follow- ing requirements as to tensile properties : Tensile strength, Ib. per sq. in. 55,000-65,000 Yield point, min., per sq. in 0.5 tens. str. 1,500,000 Elongation in 8 in., min., per cent* Tens. str. Elongation in 2 in., min., per cent 22 *See Par. 68. b The yield point shall be determined by the drop of the beam of the testing machine. 68 Modifications in Elongation, a For bars over % in. in thickness or diameter a deduction of 1 from the percentage of elonga- tion in 8 in. specified in Par. 67, shall be made for each increase of % in. in thickness or diameter above % in., to a minimum of 18 per cent. b For bars under 5/16 in. in thickness or diameter a deduction of 2.5 from the percentage of elongation in 8 in. specified in Par. 67, shall be made for each decrease of 1/16 in. in thickness or diameter below 5/16 in. 69 Bend Tests, a The test specimen shall bend cold through 180 deg. without cracking on the outside of the bent portion, as fol- lows : For material % in. or under in thickness or diameter flat on itself; for material over % in. to and including li/4 in. in thickness or diameter around a pin the diameter of which is equal to the thickness or diameter of the specimen ; and for material over l 1 /^ in. in thickness or diameter around a pin the diameter of which is equal to twice the thickness or diameter of the specimen. o The test specimen for bars over iy 2 in. in thickness or diameter when prepared as specified in Par. 70, shall bend cold through 180 deg. around a 1-in. pin without cracking on the outside of the bent portion. 70 Test Specimens, a Tension and bend test specimens except as specified in b, shall be of the full thickness of material as rolled. They may be machined to the form and dimensions shown in Fig. 1, or may have both edges parallel. b Tension test specimens for bars over 1% in. in thickness or diameter may be of the form and dimensions shown in Fig. 4. Bend NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 21 test specimens may be 1 by % in. in section. The axis of the specimen shall be located at any point midway between the center and surface and shall be parallel to the axis of the bar. 71 Number of Tests, a One tension and one bend test shall be made from each melt; except that if material from one melt differs % in. or more in thickness, one tension and one bend test shall be made from both the thickest and the thinnest material rolled. l> If any test specimen shows defective machining or develops flaws, it may be discarded and another specimen substituted. c If the percentage of elongation of any tension test specimen is less than that specified in Par. 67, and any part of the fracture is more than % in. from the center of the gage length of a 2-in. specimen or is outside the middle third of the gage length of an 8-in. specimen, as indicated by scribe scratches marked on the specimen before testing, a retest shall be allowed. IV PERMISSIBLE VARIATIONS IN GAGE 72 Permissible Variation. The thickness or cross-section of each piece of steel shall not vary under that specified more than 2.5 per cent. (XOTE: Overweight variation is a matter of contract between the steel manufacturer and boiler builder.) V FINISH 73 Finish. The finished material shall be free from injurious defects and shall have a workmanlike finish. VI MARKING 74 Marking. Bars shall, when loaded for shipment, be properly separated and marked with the name or brand of the manufacturer and melt number for identification. The melt number shall be legibly marked on each test specimen. VII INSPECTION AND REJECTION 75 Inspection. The inspector representing the purchaser shall have free entry, at all times while work on the contract of the pur- chaser is being performed, to all parts of the manufacturer's works 22 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. which concern the manufacture of the material ordered. The manu- facturer shall afford the inspector, free of cost, all reasonable facilities to satisfy him that the material is being furnished in accordance with these specifications. All tests and inspection shall be made at the place of manufacture prior to shipment, unless otherwise specified, and shall be so conducted as not to interfere unnecessarily with the operation of the works. 76 Rejection. Material which shows injurious defects subsequent to its acceptance at the manufacturer's works will be rejected, and the manufacturer shall be notified. SPECIFICATIONS FOR STEEL CASTINGS THESE SPECIFICATIONS ARE ABSTRACTED FROM THOSE FOR STEEL CASTINGS OF THE AMERICAN SOCIETY FOR TESTING MATERIALS, SERIAL DESIGNATION A 27-14. 77 Classes. These specifications cover two classes of castings, namely : Class A, ordinary castings for which no physical requirements are specified. Class B, castings for which physical requirements are specified. These are of three grades: hard, medium, and soft. 78 Patterns, a Patterns shall be made so that sufficient finish is allowed to provide for all variations in shrinkage. & Patterns shall be painted three colors to represent metal, cores, and finished surfaces. It is recommended that core prints shall be painted black and finished surfaces red. 79 Basis of Purchase. The purchaser shall indicate his intention to substitute the test to destruction specified in Par. 87, for the tension and bend tests, and shall designate the patterns from which castings for this test shall be made. I MANUFACTURE 80 Process. The steel may be made by the open-hearth, crucible, or any other process approved by the purchaser. 81 Heat Treatment, a Class A castings need not be annealed unless so specified. b Class B castings shall be allowed to become cold. They shall then be uniformly reheated to the proper temperature to refine the NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 23 grain (a group thus reheated being known as an "annealing charge"), and allowed to cool uniformly and slowly. If, in the opinion of the purchaser or his representative, a casting is not properly annealed, he may at his option require the casting to be re-annealed. II CHEMICAL PROPERTIES AND TESTS 82 Chemical Composition. The castings shall conform to the following requirements as to chemical composition : Class A Class B Carbon not over 0.30 per cent Phosphorus not over 0.06 per cent not over 0.05 per cent Sulphur not over 0.05 per cent 83 Ladle Analyses. An analysis to determine the percentages of carbon, manganese, phosphorus and sulphur shall be made by the man- ufacturer from a test ingot taken during the pouring of each melt, a copy of which shall be given to the purchaser or his representative. This analysis shall conform to the requirements specified in Par. 82. Drillings for analysis shall be taken not less than 14 i n - beneath the surface of the test ingot. 84 Clieck Analyses, a Analyses of Class A castings may be made by the purchaser, in which case an excess of 20 per cent above the requirement as to phosphorus specified in Par. 8\2, shall be allowed. Drillings for analysis shall be taken not less than ^4 in beneath the surface. I Analyses of Class B castings may be made by the purchaser from a broken tension or bend test specimen, in which case an excess of 20 per cent above the requirements as to phosphorus and sulphur specified in Par. 82, shall be allowed. Drillings for analysis shall be taken not less than y in. beneath the surface. Ill PHYSICAL PROPERTIES AND TESTS (For Class B Castings only.) 85 Tension Tests, a The castings shall conform to the follow- ing minimum requirements as to tensile properties: 24 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. Hard Medium Soft Tensile strength, Ib. per sq. in 80,000 70,000 60,000 Yield point, Ib. per sq. in 36,000 31,500 27,000 Elongation in 2 in., per cent 15 18 22 Eeduction of area, per cent 20 25 30 & The yield point shall be determined by the drop of the beam of the testing machine. 86 Bend Tests, a The test specimen for soft castings shall bend cold through 1,20 deg., and for medium castings through 90 deg., around a 1-in. pin, without cracking on the outside of the bent portion. & Hard castings shall not be subject to bend test requirements. 87 Alternative Tests to Destruction. In the case of small or un- important castings, a test to destruction on three castings from a lot may be substituted for the tension and bend tests. This test shall show the material to be ductile, free from injurious defects, and suitable for the purpose intended. A lot shall consist of all castings from one melt, in the same annealing charge. 88 Test Specimens, a Sufficient test bars, from which the test specimens required in Par. 89, may be selected, shall be attached to castings weighing 500 Ib. or over, when the design of the castings will permit. If the castings weigh less than 500 Ib., or are of such a design that test bars cannot be attached, two test bars shall be cast to represent each melt; or the quality of the castings shall be determined by tests to destruction as specified in Par. 87. All test bars shall be annealed with the castings they represent. & The manufacturer and purchaser shall agree whether test bars can be attached to castings, on the location of the bars on the castings, on the castings to which bars are to be attached, and on the method of casting unattached bars. c Tension test specimens shall be of the form and dimensions shown in Fig. 4. Bend test specimens shall be machined to 1 by ^ in. in section with corners rounded to a radius not over 1/16 in. 89 Number of Tests, a One tension and one bend test shall be made from each annealing charge. If more than one melt is repre- sented in an annealing charge, one tension and one bend test shall be made from each melt. & If any test specimen shows defective machining or develops flaws, it may be discarded; in which case the manufacturer and the purchaser or his representative shall agree upon the selection of an- other specimen in its stead. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 25 c If the percentage of elongation of any tension test specimen is less than that specified in Par. 85, and any part of the fracture is more than % in. from the center of the gaged length, as indicated by scribe scratches marked on the specimen before testing, a retest shall be allowed. IV WORKMANSHIP AND FINISH 90 Workmanship. The castings shall substantially conform to the sizes and shapes of the patterns, and shall be made in a workman- like manner.' 91 Finish, a The castings shall be free from injurious defects. b Minor defects which do not impair the strength of the castings may, with the approval of the purchaser or his representative, be FIG. 4 STANDARD FORM OF TEST SPECIMEN REQUIRED FOR ALL TENSION TESTS OF STEEL CASTING MATERIAL welded by an approved process. The defects shall first be cleaned out to solid metal; and after welding, the castings shall be annealed, if specified by the purchaser or his representative. c The castings offered for inspection shall not be painted or covered with any substance that will hide defects, nor rusted to such an extent as to hide defects. V INSPECTION AND EEJECTION 92 Inspection. The inspector representing the purchaser snail have free entry, at all times while work on the contract of the pur- chaser is being performed, to all parts of the manufacturer's works which concern the manufacture of the castings ordered. The manu- facturer shall afford the inspector, free of cost, all reasonable facilities to satisfy him that the castings are being furnished in accordance with 26 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. these specifications. All tests (except check analyses) and inspection shall be made at the place of manufacture prior to shipment, unless otherwise specified, and shall be so conducted as not to interfere un- necessarily with the operation of the works. 93 Rejection, a Unless otherwise specified, any rejection based on tests made in accordance with Par. 84, shall be reported within five working days from the receipt of samples. ft Castings which show injurious defects subsequent to their ac- ceptance at the manufacturer's works will be rejected, and the manu- facturer shall be notified. 94 Rehearing. Samples tested in accordance with Par. 84, which represent rejected castings, shall be preserved for two weeks from the date of the test report. In case of dissatisfaction with the results of the tests, the manufacturer may make claim for a rehearing within that time. SPECIFICATIONS FOR GRAY IRON CASTINGS THESE SPECIFICATIONS ARE IDENTICAL WITH THOSE OF THE AMERICAN SOCIETY FOR TESTING MATERIALS, SERIAL DESIGNATION A 48-05. 95 Process of Manufacture. Unless furnace iron is specified, all gray castings are understood to be made by the cupola process. 96 Chemical Properties. The sulphur contents to be as follows : Light castings not over 0.08 per cent Medium castings not over 0.10 per cent Heavy Castings not over 0.12 per cent 97 Classification. In dividing castings into light, medium and heavy classes, the following standards have been adopted : 98 Castings having any section less than % i n - thick shall be known as light castings. 99 Castings in which no section is less than 2 in. thick shall be known as heavy castings. 100 Medium castings are those not included in the above classifi- cation. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS PHYSICAL PROPERTIES AND TESTS 27 101 Transvers-e Test. The minimum breaking strength of the "Arbitration Bar" under transverse load shall be not under: Light castings 2500 Ibs. Medium castings 2900 Ibs. Heavy castings 3300 Ibs. In no case shall the deflection be under 0.10 in. 102 Tensile Test. Where specified, this shall not run less than : Light castings 18,000 Ib. per sq. in. Medium castings 21,000 Ib. per sq. in. Heavy castings 24,000 Ib. per sq. in. Sfcf. Thread FIG. 5 STANDARD FORM OF TEST SPECIMEN EEQUIRED FOR TENSION TESTS OF GRAY-IRON CASTING MATERIAL 103 Arbitration Bar. The quality of the iron going into castings under specification shall be determined by means of the "Arbitration Bar." This is a bar 1*4 in. in diameter and 15 in. long. It shall be prepared as stated further on and tested transversely. The tensile, test is not recommended, but in case it is called for, the bar as shown in Fig. 5, and turned up from any of the broken pieces of the trans- verse test shall be used. The expense of the tensile test shall fall on t the purchaser. 101 Number of Test Bars. Two sets of two bars shall be cast from each heat, one set from the first and the other set from the last iron going into the castings. Where the heat exceeds twenty tons, an additional set of two bars shall be cast for each twenty tons or fraction thereof above this amount. In case of a change of mixture during the heat, one set of two bars shall also be cast for every mixture other 28 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. than the regular one. Each set of two bars is to go into a single mold. The bars shall not be rumbled or otherwise treated, being simply brushed off before testing. 105 Method of Testing. The transverse test shall be made on all the bars cast, with supports 12 in. apart, load applied at the middle, PATTERN _ eg < - t > IO" P'ipe Cope POURING BASIN I I FIG. 6 DETAILS OF PATTERN AND MOLD REQUIRED FOR ARBITRATION BARS IN TESTING GRAY-IRON CASTING MATERIAL and the deflection at rupture noted. One bar of every two of each set made must fulfill the requirements to permit acceptance of the cast- ings represented. 106 Mold for Test Bar. The mold for the bars is shown in Fig. 6. The bottom of the bar is 1/16 in. smaller in diameter than the top, to allow for draft and for the strain of pouring. The pattern shall not be rapped before withdrawing. The flask is to be rammed up NEW INSTALLATIONS, TART I, SECTION I, POWER BOILERS 29 with green molding sand, a little damper than usual, well mixed and put through a ^"o. 8 sieve, with a mixture of one to twelve bituminous facing. The mold shall be rammed evenly and fairly hard, thoroughly dried and not cast until it is cold. The test bar shall not be removed from the mold until cold enough to be handled. 107 Speed of Testing. The rate of application of the load shall be from 20 to 40 seconds for a deflection of 0.10 in. 108 Samples for Analysis. Borings from the broken pieces of the "Arbitration Bar" shall be used for the sulphur determinations. One determination for each mold made shall be required. In case of dispute, the standards of the American Foundrymen's Association shall be used for comparison. 109 Finish. Castings shall be true to pattern, free from cracks, flaws and excessive shrinkage. In other respects they shall conform to whatever points may be specially agreed upon. 110 Inspection. The inspector shall have reasonable facilities afforded him by the manufacturer to satisfy him that the finished material is furnished in accordance with these specifications. All tests and inspections shall, as far as possible, be made at the place of manufacture prior to shipment. SPECIFICATIONS FOR MALLEABLE CASTINGS THESE SPECIFICATIONS ARE IDENTICAL, WITH THOSE OF THE AMERICAN SOCIETY FOR TESTING MATERIALS, SERIAL DESIGNATION A 47-04. 111 Process of Manufacture. Malleable iron castings may be made by the open-hearth, air furnace, or cupola process. Cupola iron, however, is not recommended for heavy nor for important castings. 112 Chemical Properties. Castings for which physical require- ments are specified shall not contain over 0.06 sulphur nor over 0.225 phosphorus. PHYSICAL PROPERTIES AND TESTS 113 Standard Test Bar. This bar shall be 1 in. sq. and 14 in. long, without chills and with ends left perfectly free in the mold. Three shall be cast in one mold, heavy risers insuring sound bars. Where the full heat goes into castings which are subject to specifica- 30 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. tion, one mold shall be poured two minutes after tapping into the first ladle, and another mold from the last iron of the heat. Molds shall be suitably stamped to insure identification of the bars, the bars being annealed with the castings. Where only a partial heat is required for the work in hand, one mold should be cast from the first ladle used and another after the required iron has been tapped. a Of the three test bars from the two molds required for each heat, one shall be tested for tensile strength and elongation, the other for transverse strength and deflection. The other remaining bar is reserved for either the transverse or tensile test, in case of the failure of the two other bars to come up to requirements. The halves of the bars broken transversely may also be used for the tensile test. b Failure to reach the required limit for the tensile strength with elongation, as also the transverse strength with deflection, on the part of at least one test, shall reject the castings from that heat. 114 Tensile Test. The tensile strength of a standard test bar for castings under specification shall not be less than 40,000 Ib. per sq. in. The elongation measured in 2 in. shall *ot be less than %y% per cent. 115 Transverse Test. The transverse strength of a standard test bar, on supports 12 in. apart, pressure being applied at the center, shall not be less than 3000 Ib., deflection being at least y 2 in. 116 Test Lugs. Castings of special design or of special impor- tance may be provided with suitable test lugs at the option of the inspector. At least one of these lugs shall be left on the casting for his inspection upon his request therefor. 117 Annealing. Malleable castings shall neither be "over" nor "under" annealed. They must have received their full heat in the oven at least sixty hours after reaching that temperature. 118 The "saggers" shall not be dumped until the contents shall at least be "black hot." 119 Finish. Castings shall be true to pattern, free from blemishes, scale or shrinkage cracks. A variation of 1/16 in. per foot shall be permissible. Founders shall not be held responsible for defects due to irregular cross sections and unevenly distributed metal. 120 Inspection. The inspector representing the purchaser shall have all reasonable facilities given him by the founder to satisfy him that the finished material is furnished in accordance with these specifications. All tests and inspections shall be made prior to ship- ment. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 31 SPECIFICATIONS FOR BOILER RIVET IRON THESE REQUIREMENTS ARE AN ADAPTATION, WITH SLIGHT MODI- FICATIONS IN THE PHYSICAL PROPERTIES AND TESTS, OF THE SPECI- FICATIONS FOR ENGINE BOLT IRON OF THE AMERICAN SOCIETY FOR TESTING MATERIALS. A REQUIREMENTS FOR ROLLED BARS I MANUFACTURE 121 Process. The iron shall be made wholly from puddled iron or knobbled charcoal iron, and shall be free from any admixture of iron scrap or steel. 122 Iron Scrap. This term applies only to foreign or bought scrap and does not include local mill products free from foreign or bought scrap. II PHYSICAL PROPERTIES AND TESTS 123 Tension Tests, a The iron shall conform to the following requirements as to tensile properties: Tensile strength, Ib. per sq. in 48.000-52,000 Yield point, min., Ib. per sq. in 0.6 tens. str. Elongation in 8 in., min., per cent 28 Eeduction of area, min., per cent 45 b The yield point shall be determined by the drop of the beam of the testing machine. The speed of the cross-head of the machine shall not exceed li/o in. per minute. 124 Bend Tests, a Cold-lend Tests The test specimen shall bend cold through 180 deg. flat on itself without cracking on the out- side of the bent portion. I Hot-bend Tests The test specimen, when heated to a bright cherry red, shall bend through 180 deg. flat on itself, without fracture on the outside of the bent portion. c Nick-bend Tests The test specimen, when nicked 25 per cent around with a tool having a 60-deg. cutting edge, to a depth of not less than 8 nor more than 1.6 per cent of the diameter of the specimen, and broken, shall show a wholly fibrous fracture. d Bend tests may be made by pressure or by blows. 32 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E 125 Etch Tests. 1 The cross-section of the test specimen shall be ground or polished, and etched for a sufficient period to develop the structure. This test shall show the material to be free from steel. 126 Test Specimens. All test specimens shall be of the full sec- tion of material as rolled. 127 Number of Tests, a Bars of one size shall be sorted into lots of 100 each. Two bars shall be selected at random from each lot or fraction thereof, and tested as specified in Pars. 123 and 124; but only one of these bars shall be tested as specified in Par. 125. I If any test specimen from either of the bars originally selected to represent a lot of material, contains surface defects not visible before testing but visible after testing, or if a tension test specimen breaks outside the middle third of the gage length, one retest from a different bar will be allowed. Ill PERMISSIBLE VARIATIONS IN GAGE 128 Permissible Variations. The gage of each bar shall not vary more than 0.01 in. from that specified. IV FINISH 129 Finish. The bars shall be smoothly rolled and free from slivers, depressions, seams, crop ends and evidences of being burnt. V MARKING 130 Marking. The bars shall be stamped or marked as desig- nated by the purchaser. VI INSPECTION AND REJECTION 131 Inspection, a The inspector representing the purchaser shall have free entry at all times, while work on the contract of the purchaser is being performed, to all parts of the manufacturer's works which concern the manufacture of the material ordered. The manu- facturer shall afford the inspector, free of cost, all reasonable facilities to satisfy him that the material is being furnished in accordance with *A solution of two parts water, one part concentrated hydrochloric acid, and one part concen- trated sulphuric acid is recommended for the etch test. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 33 these specifications. Tests and inspection at the place of manufacture shall be made prior to shipment. b The purchaser may make the tests to govern the acceptance or rejection of material in his own laboratory or elsewhere. iSuch tests, however, shall be made at the expense of the purchaser. 132 Rejection. If either of the test bars selected to represent a lot does not conform to the requirements specified in Pars. 1.23, 124 and 125, the lot will be rejected. B REQUIREMENTS FOR RIVETS I PHYSICAL PROPERTIES AND TESTS 133 Number of Tests. When specified, three rivets of each di- ameter shall be taken at random from each lot offered for inspection, and if they fail to stand the following tests the lot will be rejected. 134 Bend Tests, a The rivet shank shall bend cold through 180 deg. flat on itself, as shown in Fig. .2, without cracking on the out- side of the bent portion. & The heads must stand bending back, showing that they are firmly joined. c When nicked and broken gradually the fracture must show a clean, long and fibrous iron. II WORKMANSHIP AND FINISH 135 Workmanship. The rivets shall be true to form, concentric, and shall be made in a workmanlike manner. 136 Finish. The finished rivets shall be free from injurious de- fects. Ill INSPECTION AND REJECTION 137 Inspection. The inspector representing the purchaser shall have free entry at all times, while work on the contract of the pur- chaser is being performed, to all parts of the manufacturer's works which concern the manufacture of the rivets ordered. The manu- facturer shall afford the inspector, free of cost, all reasonable facilities to satisfy him that the rivets are being furnished in accordance with these specifications. All tests and inspection shall be made at the 34 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. place of manufacture prior to shipment, unless otherwise specified, and shall be so conducted as not to interfere unnecessarily with the opera- tion of the works. 138 Rejection. Rivets which show injurious defects subsequent to their acceptance at the manufacturer's works will be rejected, and the manufacturer shall be notified. SPECIFICATIONS FOR STAYBOLT IRON THESE SPECIFICATIONS ARE IDENTICAL, WITH THOSE OF THE AMERICAN SOCIETY FOR TESTING MATERIALS, SERIAL DESIGNATION A 39-14. I MANUFACTURE 139 Process. The iron shall be rolled from a bloom or boxpile, made wholly from puddled iron or knobbled charcoal iron. The puddle mixture and the component parts of the bloom or boxpile shall be free from any admixture of iron scrap or steel. 140 Definition of Terms, a Bloom A bloom is a solid mass of iron that has been hammered into a convenient size for rolling. b Boxpile A boxpile is a pile, the sides, top and bottom of which are formed by four flat bars and the interior of which consists of a number of small bars the full length of the pile. c Iron Scrap This term applies only to foreign or purchased scrap and does not include local mill products free from foreign or purchased scrap. II PHYSCIAL PROPERTIES AND TESTS 141 Tension Tests, a The iron shall conform to the following requirements as to tensile properties: Tensile strength, Ib. per sq. in 49,000-53,000 Yield point, min., Ib. per sq. in 0.6 tens. str. Elongation in 8 in., min., per cent 30 Keduction of area, min., per cent 48 b The yield point shall be determined by the drop of the beam of the testing machine. The speed of the cross-head of the machine shall not exceed 1% in. per minute. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 35 142 Bend Tests, a Cold-bend Tests The test specimen shall bend cold through 180 deg. flat on itself in both directions without fracture on the outside of the bent portion. b Quench-bend Tests The test specimen, when heated to a yel- low heat and quenched at once in water the temperature of which is between 80 deg. and 90 deg. fahr., shall bend through 180 deg. flat on itself without fracture on the outside of the bent portion. c Nick-lend Tests The test specimen, when nicked 25 per cent around with a tool having a 60-deg. cutting edge, to a depth of not less than 8 nor more than 16 per cent of the diameter of the specimen, and broken, shall show a clean fiber entirely free from crystallization. d Bend tests may be made by pressure or by blows. 143 Etch Tests. 1 The cross-section of the test specimen shall be ground or polished, and etched for a sufficient period to develop the structure. This test shall show the material to have been rolled from a bloom or a boxpile, and to be free from steel. 144 Test Specimens. All test specimens shall be of the full sec- tion of material as rolled. 145 Number of Tests, a Bars of one size shall be sorted into lots of 100 each. Two bars shall be selected at random from each lot or fraction thereof, and tested as specified in Pars. 141 and 142; but only one of these bars shall be tested as specified in Par. 143. b If any test specimen from either of the bars originally selected to represent a lot of material, contains surface defects not visible be- fore testing but visible after testing, or if a tension test specimen breaks outside the middle third of the gage length, one retest from a different bar will be allowed. c "When retests as specified in ~b are not permitted, a reduction of 2 per cent in elongation and 3 per cent in reduction of area from that specified in Par. 141, shall be allowed. Ill PERMISSIBLE VARIATIONS IN GAGE 146 Permissible Variations. The bars shall be truly round within 0.01 in., and shall not vary more than 0.005 in. above or more than 0.01 in. below the specified size. J A nolution of two parts water, one part concentrated hydrochloric acid, and one part-concen_ trated sulphuric acid is recommended for the etch test. 36 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. IV FINISH 147 Finish. The bars shall be smoothly rolled and free from slivers, depressions, seams, crop ends and evidences of being burnt. V MARKING 148 Marking. The bars shall be stamped or marked as desig- nated by the purchaser. VI INSPECTION AND REJECTION 149 Inspection, a The inspector representing the purchaser shall have free entry, at all times while work on the contract of the purchaser is being performed, to all parts of the manufacturer's works which concern the manufacture of the material ordered. The manu- facturer shall afford the inspector, free of cost, all reasonable facilities to satisfy him that the material is being furnished in accordance with these specifications. Tests and inspection at the place of manufacture shall be made prior to shipment. b The purchaser may make the tests to govern the acceptance or rejection of material in his own laboratory or elsewhere. Such tests, however, shall be made at the expense of the purchaser. 150 Rejection, a If either of the test bars selected to represent a lot does not conform to the requirements specified in Pars. 141, 142 and 143, the lot will be rejected. b Bars which will not take a clean, sharp thread with dies in fair condition, or which develop defects in forging or machining, will be rejected, and the manufacturer shall be notified. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 37 SPECIFICATIONS FOR REFINED WROUGHT-IRON BARS THESE SPECIFICATIONS ARE SIMILAR TO THOSE OF THE AMERICAN SOCIETY FOR TESTING MATERIALS, SERIAL DESIGNATION A 41-13. I MANUFACTURE 151 Process. Befined wrought-iron bars shall be made wholly from puddled iron, and may consist either of new muck-bar iron or a mixture of muck-bar iron and scrap, but shall be free from any ad- mixture of steel. II PHYSICAL PROPERTIES AND TESTS 152 Tension Tests, a The iron shall conform to the following minimum requirements as to tensile properties. Tensile strength, Ib. per sq. in 48,000 (See Pars. 153 and 154.) Yield point, Ib. per sq. in 25,000 Elongation in 8 in., per cent 22 (See Par. 155.) b The yield point shall be determined by the drop of the beam of the testing machine. The speed of the cross-head of the machine shall not exceed 1^2 in- per minute. 153 Permissible Variations. Twenty per cent of the test speci- mens representing one size may show tensile strengths 1000 Ib. per sq. in. under, or 5000 Ib. per sq. in. over that specified in Par. 152; but no specimen shall show a tensile strength under 45,000 Ib. per sq. in. 154 Modifications in Tensile Strength. For flat bars which have to be reduced in width, a deduction of 1000 Ib. per sq. in. from the tensile strength specified in Pars. 152 and 153, shall be made. 155 Permissible Variations in Elongation. Twenty per cent of the test specimens representing one size may show the following per- centages of elongation in 8 in. : BOUND BAES % in. or over, tested as rolled 20 per cent Under % in., tested as rolled 16 per cent Reduced by machining 18 per cent 38 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. PLAT BAES % in. or over, tested as rolled 18 per cent Under % in., tested as rolled 16 per cent Reduced by machining 16 per cent 156 Bend Tests, a Cold-bend Tests Cold bend tests will be made only on bars baving a nominal area of 4 sq. in. or under, in which case the test specimen shall bend cold through 180 deg. without fracture on the outside of the bent portion, around a pin the diameter of which is equal to twice the diameter or thickness of the specimen. b Hot-bend Tests The test specimen, when heated to a tempera- ture between 1700 deg. and 1800 deg. fahr., shall bend through 180 deg. without fracture on the outside of the bent portion, as follows : for round bars under 2 sq. in. in section, flat on itself; for round bars 2 sq. in. or over in section and for all flat bars, around a pin the diameter of which is equal to the diameter or thickness of the specimen. c Nick-bend Tests The test specimen, when nicked 25 per cent around for round bars, and along one side for flat bars, with a tool having a 60-deg. cutting edge, to a depth of not less than 8 nor more than 16 per cent of the diameter or thickness of the specimen, and broken, shall not show more than 10 per cent of the fracture surface to be crystalline. d Bend tests may be made by pressure or by blows. 157 Etch Tests. 1 The cross-section of the test specimen shall be ground or polished, and etched for a sufficient period to develop the structure. This test shall show the material to be free from steel. 158 Test Specimens, a Tension and bend test specimens shall be of the full section of material as rolled, if possible; otherwise the specimens shall be machined from the material as rolled. The axis of the specimen shall be located at any point one-half the distance from the center to the surface of round bars, or from the center to the edge of flat bars, and shall be parallel to the axis of the bar. b Etch test specimens shall be of the full section of material as rolled. 159 Number of Tests, a All bars of one size shall be piled separately. One bar from each 100 or fraction thereof will be selected at random and tested as specified. b If any test specimen from the bar originally selected to repre- sent a lot of material contains surface defects not visible before test- 1 A. solution of two parts water, one part concentrated hydrochloric acid, and one part con- centrated sulphuric acid is recommended for the etch test. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 39 ing but visible after testing, or if a tension test specimen breaks outside the middle third of the gage length, one retest from a different bar will be allowed. Ill PERMISSIBLE VARIATIONS IN GAGE 160 Permissible Variations, a Round bars shall conform to the standard limit gages adopted by the Master Car Builders' Association given in Table 2. TABLE 2 PERMISSIBLE VARIATIONS IN GAGE FOR ROUND WROUGHT-IRON BARS Nominal Diameter, Inches Maximum Diameter, Inches Minimum Diameter, Inches Total Variation, Inches y 2550 . 2450 0.010 s 3180 3070 Oil Y 0.3810 . 3690 0.012 T 0.4440 4310 0.013 J> 5070 4930 014 A . 0.5700 . 5550 0.015 8 6330 6170 016 0.7585 0.7415 0.017 H 8840 8660 0.018 1 1.0095 0.9905 0.019 iu . 1 . 1 350 1.1150 0.020 J3 1 2605 1 2395 0.021 1) The widths or thicknesses of flat bars shall not vary more than 2 per cent from that specified. IY FINISH 161 Finish. The bars shall be smoothly rolled and free from slivers, depressions, seams, crop ends and evidences of being burnt. V INSPECTION AND REJECTION 162 Inspection, a The inspector representing the purchaser shall have free entry, at all times while work on the contract of the purchaser is being performed, to all parts of the manufacturer's works which concern the manufacture of the material ordered. The manufacturer shall afford the inspector, free of cost, all reasonable facilities to satisfy him that the material is being furnished in ac- cordance with these specifications. Tests and inspection at the place of manufacture shall be made prior to shipment. 1) The purchaser may make the tests to govern the acceptance or rejection of material in his own laboratory or elsewhere. Such tests, however, shall be made at the expense of the purchaser. 40 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. 163 Rejection. All bars of one size will be rejected if the test specimens representing that size do not conform to the requirements specified. SPECIFICATIONS FOR LAPWELDED AND SEAMLESS BOILER TUBES Approved by the Boiler Tube Manufacturers of America September 25, 1914 I MANUFACTURE 164 Process, a Lapwelded tubes shall be made of open-hearth steel or knobbled hammered charcoal iron. & Seamless tubes shall be made of open-hearth steel. II HEMICAL PROPERTIES AND TESTS 16-5 Cliemical Composition, a The steel shall conform to the following requirements as to chemical composition: Carbon 0.08-0.18 per cent Manganese 0.30-0.50 per cent Phosphorus not over 0.04 per cent Sulphur not over 0.045 per cent b Chemical analyses will not be required for charcoal iron tubes. 166 Check Analyses, a Analyses of two tubes in each lot of 250 (or on total order if less than 250) may be made by the purchaser which shall conform to the requirements specified in Par. 165. Drill- ings for analyses shall be taken from several points around each tube. I) If the analysis of only one tube does not conform to the re- quirements specified, analyses of two additional tubes from the same lot shall be made, each of which shall conform to the requirements specified. III PHYSICAL PROPERTIES AND TESTS 167 Flange Test, a A test specimen not less than 4 in. in length shall have a flange turned over at right angles tothe body of the tube NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 41 without showing cracks or flaws. This flange as measured from the outside of the tube shall be % in. wide. b In making the flange test, the flaring tool and die block as shown in Fig. 7, may be used. 168 Flattening Tests. A test specimen 3 in. in length shall stand hammering flat until the inside walls are brought parallel and separated by a distance equal to three (3) times the wall thickness, without showing cracks or flaws. In the case lapwelded tubes, the test shall be made with the weld at the point of maximum bend. FLARING TOOL A - O.S. Diatn. of Tube less a. . . . - Position after using Flarinq Tool V Position after using ' Flatter k-A DIE BLOCK A= O.S. Diam. of Tube + FIG. 7 DETAILS OF FLARING TOOL AND DIE BLOCK KEQUIRED FOR MAKING FLANGE TESTS OF BOILER TUBES 169 Hydrostatic Tests. Tubes under 5 in. in diameter shall stand an internal hydrostatic pressure of 1000 Ib. per sq. in. and tubes 5 in. in diameter or over, an internal hydrostatic pressure of 800 Ib. per sq. in. Lapwelded tubes shall be struck near both ends, while under pres- sure, with a two-pound hand hammer or the equivalent. 170 Test Specimens, a All test specimens shall be taken from tubes before being cut to finished lengths and shall be smooth on the ends and free from burrs, b All tests shall be made cold. 171 Number of Tests. One flange and one flattening test shall be made from each of two tubes in each lot of 250 or less. Each tube shall be subjected to the hydrostatic test. 172 Retests. If the result of the physical tests of only one tube from any lot do not conform to the requirements specified in Pars. 167 and 168, retests of two additional tubes from the same lot shall be made, aac-h of which shall conform to the requirements specified. 42 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. ETCH TESTS FOR CHARCOAL IRON 173 Etch Tests. 1 A cross section of tube may be turned or ground to a perfectly true surface polished free from dirt or cracks, and etched until the soft parts are sufficiently dissolved for the iron tube to show a decided ridged surface with the weld very distinct, while a steel tube would show a homogeneous surface. IV WORKMANSHIP AND FINISH 174 Workmanship. The finished tubes shall be circular within 0.02 in. and the mean outside diameter shall not vary more than 0.015 in. from the size ordered. All tubes shall be carefully gaged with a B.W.GL gage and shall not be less than the gage specified, except the tubes on which the standard slot gage, specified, will go on tightly at the thinnest point, will be accepted. The length shall not be less, but may be 0.125 in. more than that ordered. 175 Finish. The finished tubes shall be free from injurious de- fects and shall have a workmanlike finish and shall be practically free from kinks, bends and buckles. V MARKING 176 Marking. The name or brand of the manufacturer, the ma- terial from which it is made, whether steel or charcoal iron, and "Tested at 1000 Ib." for tubes under 5 in. in diameter, or "Tested at 800 Ib." for tubes 5 in. in diameter or over, shall be legibly stenciled on each tube. VI INSPECTION AND REJECTION 177 Inspection. All tests and inspection shall be made at the place of manufacture. The manufacturer of boiler tubes shall furnish the purchaser of each lot of tubes a statement of the kind of material of which the tubes are made, and that the tubes have been tested and have met all the requirements of these rules. This statement shall be furnished to the manufacturer using the tubes. 178 Rejection. Tubes when inserted in the boiler shall stand expanding and beading without showing cracks or flaws, or opening at the weld. Tubes which fail in this manner will be rejected and the manufacturer shall be notified. *A solution of two parts of water, one part concentrated hydrochloric acid, and one part concentrated sulphuric acid is recommended for the etch test. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 43 CONSTRUCTION AND MAXIMUM ALLOWABLE WORKING PRESSURES FOR POWER BOILERS 179 Maximum Allowable Working Pressure. The maximum al- iowable working pressure is that at which a boiler may be operated as determined by employing the factors of safety, stresses, and dimensions designated in these Eules. Xo boiler shall be operated at a higher pressure than the maxi- mum allowable working pressure except when the safety valve or valves are blowing, at which time the maximum allowable working pressure shall not be exceeded by more than six per cent. Wherever the term maximum allowable working pressure is used herein, it refers to gage pressure, or the pressure above the atmosphere, in pounds per square inch. 180 The maximum allowable working pressure on the shell of a boiler or drum shall be determined by the strength of the weakest course, computed from the thickness of the plate, the tensile strength stamped thereon, as provided for in Par. 36, the efficiency of the longitudinal joint, or of the ligament between the tube holes in shell or drum, (whichever is the least), the inside diameter of the course, and the factor of the safety. = maximum allowable working pressure, Ib. per sq. in. where TS = ultimate tensile strength stamped on shell plates, as provided for in Par. 36, Ib. per sq. in. t = minimum thickness of shell plates in weakest course, in. E = efficiency of longitudinal joint or of ligaments between tube holes (whichever is the least) R = inside radius of the weakest course of the shell or drum, in. FS = factor of safety, or the ratio of the ultimate strength of the material to the allowable stress. For new con- structions covered in Part I, FS in the above for- mula 5. 44 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. BOILER JOINTS 181 Efficiency of a Joint. The efficiency of a joint is the ratio which the strength of the joint bears to the strength of the solid plate. In the case of a riveted joint this is determined by calculating the breaking strength of a unit section of the joint, considering each possible mode of failure separately, and dividing the lowest result by the breaking strength of the solid plate of a length equal to that of the section considered. (See Appendix, Par. 410 to 416, for detailed methods and examples.) 188 The distance between the center lines of any two adjacent rows of rivets, or the "back pitch" measured at right angles to the direction of the joint, shall be at least twice the diameter of the rivets and shall also meet the following requirements : a Where each rivet in the inner row comes midway between two rivets in the outer row, the sum of the two diagonal sections of the plate between the inner rivet and the two outer rivets shall be at least 20 per cent greater than the section of the plate between the two rivets in the outer row. & Where two rivets in the inner row come between two rivets in the outer row, the sum of the two diagonal sections of the plate between the two inner rivets and the two rivets in the outer row shall be at least 20 per cent greater than the difference in the section of the plate between the two rivets in the outer row and the two rivets in the inner row. 183 On longitudinal joints, the distance from the centers of rivet holes to the edges of the plates, except rivet holes in the ends of butt straps, shall be not less than one and one-half times the diameter of the rivet holes. 184 a Circumferential Joints. The strength of circumferential joints of boilers, the heads of which are not stayed by tubes or through braces shall be at least 50 per cent that of the longitudinal joints of the same structure. I When 50 per cent or more of the load which would act on an imstayed solid head of the same diameter as the shell, is relieved by the effect of tubes or through stays, in consequence of the reduction of the area acted on by the pressure and the holding power of the tubes and stays, the strength of the circumferential joints in the shell shall be at least 35 per cent that of the longitudinal joints. 185 When she'll plates exceed 9/16 in. in thickness in horizontal NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 4T> return tubular boilers, the portion of the plates forming the laps of the circumferential joints, where exposed to the fire or products of com- bustion, shall be planed or milled down as shown in Fig. 8, to V2 in. in thickness, provided the requirement in Par. 184 is complied with. 18-6 Welded Joints. The ultimate tensile strength of a longi- tudinal joint which has been properly welded by the forging process, shall be taken as 8,500 Ib. per sq. in., with steel plates having a range in tensile strength of 47,000 to 5.5,000 Ib. per sq. in. 187 Longitudinal Joints. The longitudinal joints of a shell or drum which exceeds 3.6 in. in diameter, shall be of butt and double- strap construction. 18i8 The longitudinal joints of a shell or drum which does not FIG. 8 CIRCUMFERENTIAL JOINT FOR THICK PLATES OF HORIZONTAL EETURN TUBULAR BOILERS exceed 36 in. in diameter, may be of lap-riveted construction; but the maximum allowable working pressure shall not exceed 100 Ib. per sq. in. 189 The longitudinal joints of horizontal return tubular boilers shall be located above the fire-line of the setting. 190 A horizontal return tubular boiler on which a longitudinal lap joint is permitted shall not have a course over 12 ft. in length. With butt and double-strap construction, longitudinal joints of any length may be used provided the plates are tested transversely to the direction of rolling, which tests shall show the standards pre- scribed under the Specifications of Boiler Plate Steel. 191 Butt straps and the ends of shell plates forming the longi- tudinal joints shall be rolled or formed by pressure, not blows, to the proper curvature. 46 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. LIGAMENTS 192 Efficiency of Ligament. When a shell or drum is drilled for tubes in a iine parallel to the axis of the shell or drum, the efficiency of the ligament between the tube holes shall be determined as follows : a When the pitch of the tube holes on every row is equal (Fig. 9 ) , the formula is : P ^ where = efficiency of ligament ; p = pitch of tube holes, in. d = diameter of tube holes, in. Longitudinal Lt'ne FIG. 9 EXAMPLE OF TUBE SPACING WITH PITCH OF HOLES EQUAL IN EVERY Eow Example: Pitch of tube holes in the drum as shown in Fig. 9 = 514 in. Diameter of tubes = 3*4 in. Diameter of tube holes = 3 9/32 in. p^d 5.253.281 0.375, efficiency of ligament longitudinal Line FIG. 10 EXAMPLE OF TUBE SPACING WITH PITCH OF HOLES UNEQUAL IN EVERY SECOND Eow b When the pitch of tube holes on any one row is unequal (as in Figs. 10 or 11), the formula is: ~ - = efficiency of ligament NEW INSTALLATIONS, TART I, SECTION I, POWER BOILERS 47 where p unit length of ligament, in. n = number of tube holes in length, p. d = diameter of tube holes, in. Example: Spacing shown in Fig. 10. Diameter of tube holes '== 3 9/32 in. pnd 32 2X3.2-81 = = 0.453, efficiency of ligament P /Ci Example: Spacing shown in Fig. 11. Diameter of tube holes = 3 9/32 in. pnd 29.255X3.281 P 29.2.5 = 0.439, efficiency of ligament Longitudinal Line FIG. 11 EXAMPLE OF TUBE SPACING WITH PITCH OF HOLES VARYING IN EVERY SECOND AND THIRD Kow 193 When a shell or drum is drilled for tube holes in a line diagonal with the axis of the shell or drum as shown in Fig. 12, the efficiency of the ligament between the tube holes shall be determined by the following methods and the lowest value used. 0.95 ( Pl d) a = efficiency 01 ligament 6 where = efficiency of ligament p^ = diagonal pitch of tube holes, in. d = diameter of tube holes, in. p = longitudinal pitch of tube holes or distance between centers of tubes in a longitudinal row, in. The constant 0.95 in formula a applies provided ^ is 1.5 or over. 48 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. Example : Diagonal pitch of tube holes in drum as shown in Fig. 12 = 6.42 iu. Diameter of tube holes = 4 1/32 in. Longitudinal pitch of tube holes = 11% in. 0.95(6.42 4.031) l = 0.353, efficiency of ligament 11.54.03.1 11.5 = 0.649, efficiency of ligament The value determined by formula a is the least and is the one that shall be used in this case. Longitudinal Line > FIG. 12 EXAMPLE OF TUBE SPACING WITH TUBE HOLES ON DIAGONAL LINES 194 Domes. The longitudinal joint of a dome 24 in. or over in diameter shall be of butt and double-strap construction, and its flange shall be double riveted to the boiler shell when the maximum allowable working pressure exceeds 100 Ib. per sq. in. The longitudinal joint of a dome less than 24 in. in diameter may be of the lap type, and its flange may be single riveted to the boiler shell provided the maximum allowable working pressure on such a dome is computed with a factor of safety of not less than 8. The dome may be located on the barrel or over the fire-box on traction, portable or stationary boilers of the locomotive type up to and including 48 in. barrel diameter. For larger barrel diameters, the dome shall be placed on the barrel. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 49 DISHED HEADS 195 Convex Heads. The thickness required in an unstayed dished head with the pressure on the concave side, when it is a seg- ment of a sphere, shall be calculated by the following formula : 2XT8 where i thickness of plate, in. P = maximum allowable working pressure, Ib. per sq. in. TS tensile strength, Ib. per sq. in. L = radius to which the head is dished, in. Where the radius is less than 80 per cent of the diameter of the shell or drum to which the head is attached the thickness shall be at least that found by the formula by making L equal to 80 per cent of the diameter of the shell or drum. Concave Heads. Dished heads with the pressure on the convex side shall have a maximum allowable working pressure equal to 60 per cent of that for heads of the same dimensions with the pressure on the concave side. When a dished head has a manhole opening, the thickness as found by these Eules shall be increased by not less than % in. 196 Yfhen dished heads are of a less thickness than called for by Par. 195, they shall be stayed as flat surfaces, no allowance being made in such staying for the holding power due to the spherical form. 197 The corner radius of an unstayed dished head measured on the concave side of the head shall not be less than iy 2 m - or more than 4 in. and within these limits shall be not less than 3 per cent of L in Par. 195. 198 A manhole opening in a dished head shall be flanged to a depth of not less than three times the thickness of the head measured from the outside. BRACED AND STAYED .SURFACES 199 The maximum allowable working pressure for various thicknesses of braced and stayed flat plates and those which by these Eules require staying as flat surfaces with braces or staybolts of uni- 50 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. form diameter symmetrically spaced, shall be calculated by the formula : where P = maximum allowable working pressure, Ib. per sq. in. t = thickness of plate in sixteenths of an inch P = maximum pitch measured between straight lines passing through the centers of the staybolts in the different rows, which lines may be horizontal, vertical or in- clined, in. C = 11,2 for stays screwed through plates not over 7/16 in. thick with ends riveted over C = 120 for stays screwed through plates over 7/16 in. thick with ends riveted over (7 = 135 for stays screwed through plates and fitted with single nuts outside of plate C = 175 for stays fitted with inside and outside nuts and outside washers where the diameter of washers is not less than OAp and thickness not less than t. If flat plates not less than % in. thick are strengthened with doubling plates securely riveted thereto and having a thickness of not less than 2/3 t, nor more than t, then the value of t in the formula shall be % of the combined thickness of the plates and the values of C given above may also be increased 15 per cent. 200 Staylolts. The ends of screwed staybolts shall be riveted over or upset by equivalent process. The outside ends of such staybolts shall be drilled with a hole at least 3/16 in. diameter to a depth ex- tending y 2 in. beyond the inside of the plates, except on boilers having a grate area not exceeding 15 sq. ft., where the drilling of the staybolts is optional. 201 When channel irons or other members are securely riveted to the boiler heads for attaching through stays the transverse stress on such members shall not exceed 12,500 Ib. per sq. in. In computing the stress, the section modulus of the member shall be used without addition for the strength of the plate. The spacing of the rivets over the supported surface shall be in conformity with that specified for staybolts. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 51 The ends of stays fitted with nuts shall not be exposed to the direct radiant heat of the fire. 203 The maximum spacing between centers of rivets attaching the crowfeet of braces to the braced surface, shall be determined by the formula in Par. 199, using 135 for value of C. The maximum spacing between the inner surface of the shell and lines parallel to the surface of the shell passing through the centers of the rivets attaching the crowfeet of braces to the head, shall be determined by the formula in Par. 199, using 160 for the value of C. TABLE 3 MAXIMUM ALLOWABLE PITCH, IN INCHES, OF SCREWED STAYBOLTS, ENDS RIVETED OVER Pressure, Lb. per Sq. In. Thickness of Plate, In. Iff y* A H A y* 1A 10 Maximum Pitch of Staybolts, In. 100 110 120 125 130 140 150 160 170 ISO 190 200 225 250 300 5M 5 4M 4M 4^ 4K 4M 4M 4 G S A 6 5M sy* 5^ sy s sy s 5 VA 4M 4^ 4^ 4K 4 7% 7 &H sy* VA VA 6 5^ 5 5 A VA 5% 5M VA Y* 4^ " sy 8 " 8 IK 7y s 7y s 7'y s VA 6M 6^ 6^ sy* 5H 5 1 A 5 %% 8 7% 7H 7^ 7H 7 6^ 6M 5^ &A &y s 7 7 A 7M 7M 6^ 6^ "sii" 8 7H 7 The formula in Par. 199 was used in computing Table 3. Where values for screwed stays with ends riveted over are required for conditions not given in Table 3, they may be computed from the formula and used, provided the pitch does not exceed S l / 2 in. 205 The distance from the edge of a staybolt hole to a straight line tangent to the edges of the rivet holes may be substituted for p for staybolts adjacent to the riveted edges bounding a stayed surface. When the edge of a stayed plate is flanged, p shall be measured from the inner surface of the flange, at about the line of rivets to the edge of the staybolts or to the projected edge of the staybolts. 52 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. 206 The distance between the edges of the staybolt holes may be substituted for p for staybolts adjacent to a furnace door or other boiler fitting, tube hole, hand hole or other opening. 207 In water leg boilers, the staybolts may be spaced at greater distances between the rows than indicated in Table 3, provided the portions of the sheet which come between the rows of staybolts have the proper transverse strength to give a factor of safety of at least 5 at the maximum allowable working pressure. 208 The diameter of a screw stay shall be taken at the bottom of the thread, provided this is the least diameter. CT0QOOOOOOOOOOOOO FIG. 13 METHOD OF DETERMINING NET AREA OF SEGMENT OF A HEAD .209 The least cross-sectional area of a stay shall be taken in calcu- lating the allowable stress, except that when the stays are welded and have a larger cross-sectional area at the weld than at some other point, in which case the strength at the weld shall be computed as well as in the solid part and the lower value used. 210 Holes for screw stays shall be drilled full size or punched not to exceed !/4 in. less than full diameter of the hole for plates over 5/16 in. in thickness, and % in. less than the full diameter of the hole for plates not exceeding 5/16 in. in thickness, and then drilled or reamed to the full diameter. The holes shall be tapped fair and true, with a full thread. 211 The ends of steel stays upset for threading, shall be thor- oughly annealed. 212 An internal cylindrical furnace which requires staying shall be stayed as a flat surface as indicated in Table 3. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 53- 213 Staying Segments of Heads. A segment of a head shall be stayed by head to head, through, diagonal, crowfoot or gusset stays, except that a horizontal return tubular boiler may be stayed as pro- vided in Pars. 225 to 229. ,214 Areas of Segments of Heads to le Stayed. The area of a segment of a head to be stayed shall be the area enclosed by lines drawn 3 in. from the shell and 2 in. from the tubes, as shown in Figs. 13 and 14. 215 In water tube boilers, the tubes of which are connected to drum heads, the area to be stayed shall be taken as the total area of the head less a 5 in. annular ring, measured from the inner circum- ference of the drum shell. oooooQOOooo OQP opo FIG. 14 METHOD OF DETERMINING NET AREA OF IRREGULAR SEGMENT OF A HEAD When such drum heads are 30 in. or less in diameter and the tube plate is stiffened by flanged ribs or gussets, no stays need be used if a hydrostatic test to destruction of a boiler or unit section built in accordance with the construction, shows that the factor of safety is at least 5. 216 In a fire tube boiler, stays shall be used in the tube sheets if the distances between the edges of the tube holes exceed the maximum pitch of staybolts given in Table 3. That part of the tube sheet which comes between the tubes and the shell, need not be stayed when the distance from the inside of the shell to the outer surface of the tubes does not exceed that given by the formula in Par. 199, using 160 for the value of C. 54 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. 217 The net area to be stayed in a segment of a head may be de- termined by the following formula : \ (H 5\ 0.608 = area to be stayed, sq. in. 3 where H distance from tubes to shell, in. R radius of boiler head, in. 218 When the portion of the head below the tubes in a horizon- tal return tubular boiler is provided with a manhole opening, the flange of which is formed from the solid plate and turned inward to a depth of not less than three times the thickness of the head, meas- ured from the outside, the area to be stayed as indicated in Fig. 14, may be reduced by 100 sq. in. The surface around the manhole shall be supported by through stays with nuts inside and outside at the front head. TABLE 4 MAXIMUM ALLOWABLE STRESSES FOR STAYS AND STAYBOLTS Description of Stays Stresses, Lb. per Sq. In. For Lengths between Supports not Exceed- ing 120 Diameters For Lengths between Supports Exceeding 120 Diameters a Unwelded stays less than twenty diameters long screwed through plates with ends riveted over. . 6 Unwelded stays and unwelded portions of welded stays, except as specified in line a 7500 9500 6000 8500 6000 e Welded portions of stays 219 When stay rods are screwed through the sheets and riveted over, they shall be supported at intervals not exceeding 6 ft. In boilers without manholes, stay rods over 6 ft. in length may be screwed through the sheets and fitted with nuts and washers on the outside. 220 The maximum allowable stress per square inch net cross sectional area of stays and staybolts shall be as given in Table 4. The length of the stay between supports shall be measured from the inner faces of the stayed plates. The stresses are based on tension only. For computing stresses in diagonal stays, see Pars. 2,21 and 222. 221 Stresses in Diagonal and Gusset Stays. Multiply the area of a direct stay required to support the surface by the slant or diagonal NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 55 length of the stay ; divide this product by the length of a line drawn at right angles to surface supported to center of palm of diagonal stay. The quotient will be the required area of the diagonal stay. A = aXL where A = sectional area of diagonal stay, sq. in. a = sectional area of direct stay, sq. in. L = length of diagonal stay, as indicated in Fig. 15, in. I = length of line drawn at right angles to boiler head or surface supported to center of palm of diagonal stay, a? indicated in Fig. 15, in. FIG. 15 MEASUREMENTS FOR DETERMINING STRESSES IN DIAGONAL STAYS Given diameter of direct stay = 1 in., a = 0.7854, L = 60 in., I 48 in. ; substituting and solving : 0.7854X60 48 = 0.981 sectional area, sq. in. Diameter = 1.11 in. = 1% in. 222 For staying segments of tube sheets such as in horizontal return tubular boilers, where L is not more than 1.15 times I for any brace, the stays may be calculated as direct stays, allowing 90 per cent of the stress given in Table 4. 223 Diameter of Pins and Area of Rivets in Brace. The sec- tional area of pins to resist double shear and bending when secured in crowfoot, sling, and similar stays shall be at least equal to three- 56 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. fourths of the required cross-sectional area of the brace. The com- bined cross section of the eye at the sides of the pin shall be at least 25 per cent greater than the required cross-sectional area of the brace. The cross-sectional area of the rivets attaching a brace to the shell or head shall be not less than one and one quarter times the re- quired sectional area of the brace. Each branch of a crowfoot shall be designed to carry two-thirds of the total load on the brace. The net sectional areas through the sides of the crowfeet, tee irons or similar fastenings at the rivet holes shall be at least equal to the re- quired rivet section. All rivet holes shall be drilled and burrs removed, and the pins shall be made a neat fit. TABLE 5 SIZES OF ANGLES REQUIRED FOR STAYING SEGMENTS OF HEADS With the short legs of the angles attached to the head of the boiler 30" Boiler 34" Boiler 30" Boiler Height of Angle Angle Angle Angle Angle Angle Angle Angle Angle Dimen- Segment, 3"x2^" 3;H"x3" 4"x3" 3^"x3" 4"x3" 5"x3" 4"x3" 5"x3" G"x33^" sion Y"\- T> A in in Fig. 16 Thick- Thick- Thick- Thick- Thick- Thick- Thick- Thick- Thick- Fig. 16 ness, ness, ness, ness, ness, ness, ness, ness, ness, inches inches inches inches inches inches inches inches inches 10 A A GH 11 A K A & A A 7 12 & A H H A A & & 7y 2 13 A A H ^ A A y s 8 14 H 5 /s 3 /s *A A H 8^ 15 y 2 % y* s /s 9 16 ~ ~ ~ " ~ ~ ~ 5 A & 9K 224: Gusset stays when constructed of triangular right-angled web plates secured to single or double angle bars along the two sides at right angles shall have a cross-sectional area (in a plane at right angles to the longest side and passing through the intersection of the two shorter sides) not less than 10 per cent greater than would be required for a diagonal stay to support the same surface, figured by the formula in Par. 2:21, assuming the diagonal stay is at the same angle as the longest side of the gusset plate. 2.25 Staying of Upper Segments of Tube Heads ly Steel Angles. When the shell of a boiler does not exceed 36 in. in diameter and is designed for a maximum allowable working pressure not exceeding 100 Ib. per sq. in., the segment of heads above the tubes may be stayed by steel angles as specified in Table 5 and Fig. 16, except that angles of NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 57 equal thickness and greater depth of outstanding leg, or of greater thickness and the same depth of outstanding leg, may be substituted for those specified. The legs attached to the heads may vary in depth 1/2 in. above or below the dimensions specified in Table 5. 226 When this form of bracing is to be placed on a boiler, the diameter of which is intermediate to or below the diameters given in Table 5, the tabular values for the next higher diameter shall govern. Eivets of the same diameter as used in the longitudinal seams of the boiler shall be used to attach the angles to the head and to connect the outstanding legs. FIG. 16 STAYING OF HEAD WITH STEEL ANGLES IN TUBULAR BOILER ,2'27 The rivets attaching angles to heads shall be spaced not over 4 in. apart. The centers of the end rivets shall be not over 3 in. from the ends of the angle. The rivets through the outstanding legs shall be spaced not over 8 in. apart ; the centers of the end rivets shall be not more than 4 in. from the ends of the angles. The ends of the angles shall be considered those of the outstanding legs and the lengths shall be such that their ends overlap a circle 3 in. inside the inner surface of the shell as shown in Fig. 16. 2-28 The distance from the center of the angles to the shell of the boiler, marked A in Fig. 16, shall not exceed the values given in Table 5, but in no case shall the leg attached to the head on the lower angle come closer than 2 in. to the top of the tubes. 58 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. 2(29 When segments are beyond the range specified in Table 5, the heads shall be braced or stayed in accordance with the requirements in these Rules. 230 Crown Bars and Girder Stays. 'Crown bars and girder stays for tops of combustion chambers and back connections, or wherever used, shall be proportioned to conform to the following formula : Maximum allowable working pressure =7 \ rV where W = extreme distance between supports, in. P = pitch of supporting bolts, in. D = distance between girders from center to center, in. d = depth of girder, in. T = thickness of girder, in. C = 7000 when the girder is fitted with one supporting bolt C = 10,000 when the girder is fitted with two or three sup- porting bolts C = 11,000 when the girder is fitted with four or five sup- porting bolts C = 11,500 when the girder is fitted with six or seven sup- porting bolts C = 12,000 when the girder is fitted with eight or more sup- porting bolts Example: Given W = 3-1 in., P = 7.5 in., D = 7.75 in., d = 7.5 in., T = 2 in.; three stays per girder, C = 10,000; then substituting in formula: Maximum allowable working pressure 10,000X7.5X7.5X2 (34-7.5) X ?.75X34 * s 16L1 lb ' P er s ^ m ' 2(31 Maximum Allowable Working Pressure on Truncated Cones. Upper combustion chambers or vertical submerged tubular boilers made in the shape of a frustum of a cone when not over 38 in. diam- eter at the large end, may be used without stays if figured by the rule for plain cylindrical furnaces (Par. 239) making D in the for- mula equal to the diameter at the large end. When over 38 in. in diameter, that portion over 30 in. in diameter shall be fully supported by staybolts or gussets to conform to the provisions for the staying of flat surfaces. 232 Stay Tubes. When stay tubes are used in multitubular NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 59 boilers to give support to the tube plates, the sectional area of such stay tubes may be determined as follows: Total section of stay tubes, sq. in. -^T- where A = area of that portion of the tube plate containing the tubes, sq. in. a = aggregate area of holes in the tube plate, sq. in. P = maximum allowable working pressure, Ib. per sq. in. T working tensile stress allowed in the tubes, not to exceed 7000 Ib. per sq. in. ,233 The pitch of stay tubes shall conform to the formula given in Par. 199, using the values of C as given in Table 6. TABLE 6. VALUES OF C FOR DETERMINING PITCH OF STAY TUBES. Pitch of Stay Tubes in the Bounding Rows When tubes have no Nuts Outside of Plates When tubes are Fitted with Nuts Outside of Plates Where there are two plain tubes between each stay tube .... Where there is one plain tube between each stay tube Where every tube in the bounding rows is a stay tube and 120 140 130 150 170 When the ends of tubes are not shielded from the action of flame or radiant heat, the values of C shall be reduced 20 per cent. The tubes shall project about 14 in. at each end and be slightly flared. Stay tubes when threaded shall not be less than 3/16 in. thick at bottom of thread ; nuts on stay tubes are not advised. For a nest of tubes C shall be taken as 140 and 8 as the mean pitch of stay tubes. For spaces be- tween nests of tubes S shall be taken as the horizontal distance from center to center of the bounding rows of tubes and C as given in Table 6. TUBE SHEETS OF COMBUSTION CHAMBERS 234 The maximum allowable working pressure on a tube sheet of a combustion chamber, where the crown sheet is not suspended from the shell of the boiler, shall be determined by the following formula : (Dd) TX 27,000 F ~- WXD 60 REPORT OF BOILER CODE COMMITTEE. AM.SOC.M.E. where P = maximum allowable working pressure, Ib. per sq. in. D = least horizontal distance between tube centers, in. d = inside diameter of tubes, in. T = thickness of tube plate, in. W = distance from tube sheet to opposite combustion chamber sheet, in. Example: Eequired the working pressure of a tube sheet sup- porting a crown sheet braced by crown bars. Horizontal distance between centers, 4% in.; inside diameter of tubes, 2.782 in.; thickness of tube sheets, 11/16 in.; distance from tube sheet to opposite com- bustion chamber sheet, 341.4 in., measured from outside of tube plate to outside of back plate; material, steel. ^Substituting and solving: P (4.12,58.782) X0.6875X27,000 34.25X4.125 = 176 lb P er ** m - 235 ,Sling stays may be used in place of girders in all cases cov- ered in Par. 2,34, provided, however, that when such sling stays are FIG. 17 PROPER LOCATION OF STAYBOLTS ADJACENT TO LONGITUDINAL JOINT IN FURNACE SHEET used, girders or screw stays of the same sectional area shall be used for securing the bottom of the combustion chamber to the boiler shell. 236 When girders are dispensed with and the top and bottom of combustion chambers are secured by sling stays or braces, the sec- tional area of such stays shall conform with the requirements of rules for stays and stayed surfaces. 237 Furnaces of Vertical Boilers. In a vertical fire-tube boiler the furnace length, for the purpose of calculating its strength and spacing staybolts over its surface, shall be measured from the center of rivets in the bottom of the water-leg to the center of rivets in the flange of the lower tube sheet. 238 When the longitudinal joint of the furnace sheet of a vertical fire-tube boiler is of lap-riveted construction and staybolted, a stay- bolt in each circular row shall be located near the longitudinal joint, as shown in Fig. 17. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 61 239 Plain Circular Furnaces. The maximum allowable working pressure for unstayed, riveted, seamless or lap welded furnaces, where the length does not exceed 6 times the diameter and where the thick- ness is at least 5/16 in. shall be determined by one or the other of the following formulae: a Where the length does not exceed 120 times the thickness of the plate P-.= ~jL[ (1S.75X? 1 ) (1.03X) } "b Where the length exceeds 120 times the thickness of the plate 4250 XT 2 ~~ LXD where P = maximum allowable working pressure, lb. per sq. in. D = outside diameter of furnace, in. L = length of furnace, in. T = thickness of furnace walls, in sixteenths of an inch. Where the furnaces have riveted longitudinal joints no deduction need be made for the joint provided the efficiency of the joint is greater than PXD divided by 1,250X2". Example. Given a furnace 26 in. in diameter, 94 in. long and 1/2 in. thick. The length exceeds 120 times the thickness of the plate, hence the formula (b) should be used. Substituting the values in this formula : 4250X8X8 P = 94X.26 ' = HI lb. per sq. in. 240 A plain cylindrical furnace exceeding 38 in. in diameter shall be stayed in accordance with the rules governing flat surfaces. 241 Circular Flues. The maximum allowable working pressure for seamless or welded flues more than 5 in. in diameter and up to and including 18 in. in diameter shall be determined by one or the other of the following formulae : a "Where the thickness of the wall is less than 0.023 times the diameter P= ~ Where the thickness of the wall is greater than 0.0:23 times the diameter 62 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. where P maximum allowable working pressure, Ib. per sq. in. D = outside diameter of flue, in. T = thickness of wall of flue, in. c The above formulae may be applied to riveted flues of the sizes specified provided the sections are not over 3 ft. in length and provided the efficiency of the joint is greater than PX& divided by 20,OOOX2\ Example. Given a flue 14 in. in diameter and 5/16 in. thick. The thickness of the wall is less than 0.0,23 times the diameter ; hence the formula (a) should be used. Substituting the values in this formula : 10,000,000X5/16X5/16X5/16 14X14X14 = 110 lk PCT Sq ' m ' 242 Adamson Type. When plain horizontal flues are made in sections not less than 18 in. in length, and not less than 5/16 in. thick : a They shall be flanged with a radius measured on the fire side, of not less than three times the thickness of the plate, and the flat portion of the flange outside of the radius shall be at least three times the diameter of the rivet holes. & The distance from the edge of the rivet holes to the edge of the flange shall be not less than the diameter of the rivet hole, and the diameter of the rivets before driving shall be at least % in- larger than the thickness of the plate. c The depth of the Adamson ring between the flanges shall be not less than three times the diameter of the rivet holes, and the ring shall be substantially riveted to the flanges. The fire edge of the ring shall terminate at or about the point of tangency to the curve of the flange, and the thickness of the ring shall be not less than % in. The maximum allowable working pressure shall be determined by the following formula : P= (18.75XZ 1 ) ( where P = maximum allowable working pressure, Ib. per sq. in. D = outside diameter of furnace, in. L length of furnace section, in. T = thickness of plate, in sixteenths of an inch. Example. Given a furnace 44 in. in diameter, 48 in. in length, and 1/2 in. thick. Substituting values in formula : NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS P= (18.75X8) (1.03X48) = 1.309 (15049.44) = 131 Ib. per sq. in. 243 The maximum allowable working pressure on corrugated furnaces, such as the Leeds suspension bulb, Morison, Fox, Purves, or Brown, having plain portions at the ends not exceeding 9 in. in length (except flues especially provided for) when new and practically circu- lar, shall be computed as follows : P CXT D where P = maximum allowable working pressure, Ib. per sq. in. T = thickness, in. not less than 5/16 in. for Leeds, Morison, Fox and Brown, and not less than 7/16 in. for Purves and other furnaces corrugated by sections not over 18 in. long. D = mean diameter, in. = 17,300, a constant for Leeds furnaces, when corrugations are not more than 8 in. from center to center and not less than 2~ L /i in. deep. C = 15,600, a constant for Morison furnaces, when corruga- tions are not less than 8 in. from center to center and the radius of the outer corrugations is not more than one half that of the suspension curve. C = 14,000, a constant for Fox Furnaces, when corrugations are not more than 8 in. from center to center and not less than 1% in. deep. C = 14,000, a constant for Purves furnaces when rib projec- tions are not more than 9 in. from center to center and not less than 1% in. deep. C 14,000, a constant for Brown Furnaces, when corrugations are not more than 9 in. from center to center and not less than 1% in. deep. C = 10,000, a constant for furnaces corrugated by sections not more than 18 in. from center to center and not less than 2~*/2 in. deep, measured from the least inside to the greatest outside diameter of the corrugations, and having the ends fitted one into the other and substan- tially riveted together, provided that the plain parts at the ends do not exceed 12 in. in length. 64 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E 1 . In calculating the mean diameter of the Morison furnace, the least inside diameter plus 2 in., may be taken as the mean diameter. 24=4: The thickness of a corrugated or ribbed furnace shall be as- certained by actual measurement. The furnace shall be drilled for a %-in. pipe tap and fitted with a screw plug that can be removed for the purpose of measurement. For the Brown and Purves furnaces, the holes shall be in the center of the second flat; for the Morison, Fox and other similar types, in the center of the top corrugation, at least as far in as the fourth corrugation from the end of the furnace. 24:5 Cast Iron Headers. The pressure allowed on a water-tube boiler, the tubes of which are secured to cast-iron or malleable-iron headers, shall not exceed 160 Ib. per sq. in. The form and size of the internal cross section of a cast-iron or malleable-iron header at any point shall be such that it will fall within a 6 in. by 7 in. rectangle. 24:6 The cast-iron used for the headers of water-tube boilers shall conform with the Specifications for Gray-iron Castings given in Pars. 95 to 110, the header to be arbitrarily classified as a "medium casting" as to physical properties and tests, and as a "light casting" as to chemical properties. .247 A cast-iron header when tested to destruction, shall withstand a hydrostatic pressure of at least 1200 Ib. per sq. in. A hydrostatic test at 400 Ib. per sq. in. gage pressure shall be made on all new headers with tubes attached. TUBES 248 Tube Holes and Ends. Tube holes shall be drilled full size from the solid plate, or they may be punched at least y 2 in. smaller in diameter than full size, and then drilled, reamed or finished full size with a rotating cutter. 249 The sharp edges of tube holes shall be taken off on both sides of the plate with a file or other tool. 250 A fire-tube boiler shall have the ends of the tubes substan- tially rolled and beaded, or welded at the firebox or combustion cham- ber end. 251 The ends of all tubes, suspension tubes and nipples shall be flared not less than % i n - over the diameter of the tube hole on all water-tube boilers and superheaters, or they may be beaded. 252 The ends of all tubes, suspension tubes and nipples of water- tube boilers and superheaters shall project through the tube sheets or headers not less than 14 in. nor more than % in. before flaring. NEW INSTALLATIONS, PART I, SECTION I, TOWER BOILERS Go RlVETIXG 2-53 Riveting. Rivet holes, except for attaching stays or angle bars to heads, shall be drilled full size with plates, butt straps and heads bolted in position ; or they may be punched not to exceed % in. less than full diameter for plates over 5/16 in. in thickness, and % in. less than full diameter for plates not exceeding 5/16 in. in thickness, and then drilled or reamed to full diameter with plates, butt straps and heads bolted in position. 254 After drilling rivet holes, the plates and butt straps shall be separated and the burrs removed. 255 Rivets. Eivets shall be of sufficient length to completely fill the rivet holes and form heads at least equal in strength to the bodies of the rivets. 256 Rivets shall be machine driven wherever possible, with suffi- cient pressure to fill the rivet holes, and shall be allowed to cool and shrink under pressure. CALKING 2f)7 Calking. The calking edges of plates, butt straps and heads shall be beveled. Every portion of the calking edges of plates, butt straps and heads shall be planed, milled or chipped to a depth of not less than % in. Calking shall be done with a round-nosed tool. MANHOLES 258 Manholes. An elliptical manhole opening shall be not less than 11 X 15 in. or 10 X 16 in. in size. A circular manhole opening shall be not less than 15 in. in diameter. 259 A manhole reinforcing ring when used, shall be of steel or wrought-iron, and shall be at least as thick as the shell plate. 260 Manhole frames on shells or drums when used, shall have the proper curvature, and on boilers over 48 in. in diameter shall be riveted to the shell or drum with two rows of rivets, which may be pitched as shown in Fig. 18. The strength of the rivets in shear on manhole frames and reinforcing rings shall be at least equal to the tensile strength of that part of the shell plate removed, on a line parallel to the axis of the shell, through the center of the manhole, or other opening. GO REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. 261 The proportions of manhole frames and other reinforcing rings to conform to the above specifications may be determined by the use of the following formulae, which are based on the assumption that the rings shall have the same tensile strength per square inch of sec- tion as, and be of not less thickness than, the shell plate removed. For a single-riveted ring: IF = 1^:77 ~\~d ?X^i For a double-riveted ring: W = ^ 7 /N FIG. 18 METHOD OP RIVETING MANHOLE FRAMES TO SHELLS OK DRUMS WITH Two Eows OF RIVETS For two single-riveted rings : W = --- y- -\-d * For two double-riveted rings : W = Where W = least width of reinforcing ring, in. ^ = thickness of shell plate, in. d = diameter of rivet when driven, in. t = thickness of reinforcing ring not less than thickness of the shell plate, in. T = tensile strength of the ring, Ib. per sq. in. of section a = net section of one side of the ring or rings, sq. in. S = shearing strength of rivet, Ib. per sq. in. of section (see Par. 16) NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 67 I = length of opening in shell in direction parallel to axis of shell, in. N = number of rivets To find the number of rivets for a single or double reinforcing ring: $6,2 Manhole plates shall be of wrought steel or shall be steel castings. ,263 The minimum width of bearing surface, for a gasket on a manhole opening shall be % in. No gasket for use on a manhole or handhole of any boiler shall have a thickness greater than 14 in. 264 A manhole shall be located in the front head, below the tubes, of a horizontal return tubular boiler 48 in. or over in diameter. Smaller boilers shall have either a manhole or a handhole below the tubes. There shall be a manhole in the upper part of the shell or head of a fire-tube boiler over 40 in. in diameter, except a vertical fire-tube boiler, or except on internally fired boilers not over 48 in. in diameter. The manhole ma} be placed in the head of the dome. Smaller boilers shall have either j manhole or a handhole above the tubes. WASHOUT HOLES 265 A traction, portable or stationary boiler of the locomotive type shall have not less than six handholes, or washout plugs, located as follows: one in the rear head below the tubes; one in the front head at or about the line of the crown sheet ; four in the lower part of the waterleg; also, where possible, one near the throat sheet. ,266 A vertical fire-tube boiler, except the boiler of a steam fire- engine, shall have not less than seven handholes, located as follows: three in the shell at or about the line of the crown sheet; one in the shell at or about the line of the fusible plug when used; three in the shell at the lower part of the waterleg. A vertical fire-tube boiler, sub- merged tube type, shall have two or more handholes in the shell, in line with the upper tube sheet. 267 A vertical fire-tube boiler of a steam fire-engine shall have at least three brass washout plugs of not less than 1-in. iron pipe size, screwed into the shell and located as follows : one at or about the line of the crown sheet ; two at the lower part of the waterleg. 68 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.B. THREADED OPENINGS 268 Threaded Openings. An opening in a boiler for a threaded pipe connection 1 in. in diameter or over shall have not less than the number of threads given in Table 7. TABLE 7 MINIMUM NUMBER OF PIPE THREADS FOR CONNECTIONS TO BOILERS Size of pipe connec- 1 and 1M iy$ and 2 2Y 2 to 4 4H to 6 7 and 8 9 and 10 12 tion, in Number of threads llj^ UH 8 8 8 8 8 per in Minimum number of 4 5 7 8 10 12 13 threads required in opening . . . Minimum thickness 0.348 0.435 0.875 1 1.25 1.5 1.625 of material re- quired to give above number of threads, in If the thickness of the material in the boiler is not sufficient to give such number of threads, there shall be a pressed steel flange, bronze composition flange, steel-cast flange or steel plate, so as to give the re- quired number of threads, constructed and riveted to the boiler in ac- cordance with methods given in Par. 261. A steam main or safety valve opening may be fitted with either a steel cast, wrought-steel or bronze composition nozzle. A feed-pipe connection may be fitted with a brass or steel boiler bushing. SAFETY VALVES 269 Safety Valve Requirements. Each boiler shall have two or more safety valves, except a boiler for which one safety valve 3-in. size or smaller is required by these Rules. 270 The safety valve capacity for each boiler shall be such that the safety valve or valves will discharge all the steam that can be generated by the boiler without allowing the pressure to rise more than six per cent above the maximum allowable working pressure, or more than six per cent above the highest pressure to which any valve is set. 271 One or more safety valves on every boiler shall be set at or below the maximum allowable working pressure. The remaining NEW INSTALLATIONS, PART I, SECTION I, TOWER BOILERS 69 valves may be set within a range of three per cent above the maximum allowable working pressure, but the range of setting of all of the valves on a boiler shall not exceed ten per cent of the highest pressure to which any valve is set. 272 .Safety valves shall be of the direct spring loaded pop type with seat and bearing surface of the disc either inclined at an angle of about 45 deg. or flat at an angle of about 90 deg. to the center line of the spindle. The vertical lift of the valve disc measured immediately after the sudden lift due to the pop may be made any amount desired up to a maximum of 0.15 in. irrespective of the size of the valve. The nominal diameter measured at the inner edge of the valve seat shall be not less than 1 in. or more than 4^ in. 273 Each safety valve shall have plainly stamped or cast on the body: a The name or identifying trade-mark of the manufacturer I The nominal diameter with the words "Bevel Seat" or "Flat Seat" c The steam pressure at which it is set to blow d The lift of the valve disc from its seat, measured immedi- ately after the sudden lift due to the pop e The weight of steam discharged in pounds per hour at the pressure for which it is set to blow. 274 The minimum capacity of a safety valve or valves to be placed on a boiler shall be determined on the basis of 6 Ib. of steam per hour per sq. ft. of boiler heating surface for water tube boilers, and 5 Ib. for all other types of power boilers, and upon the relieving capacity marked on the valves by the manufacturer, provided such marked relieving capacity does not exceed that given in Table 8. In case the relieving capacity marked on the valve or valves exceeds the maximum given in Table 8, the minimum safety valve capacity shall be determined on the basis of the maximum relieving capacity given in Table 8 for the particular size of valve and working pressure for which it was constructed. The heating surface shall be computed for that side of the boiler surface exposed to the products of com- bustion, exclusive of the superheating surface. In computing the heating surface for this purpose only the tubes, shells, tube sheets and the projected area of headers need be considered. TABLE 8 DISCHARGE CAPACITIES FOR DIRECT SPRING-LOADED POP SAFETY VALVES, WITH 45 DEG. BEVEL SEATS Gage Pres., Lb. per Sq. In Diameter, 1 In. Diameter, 1^ In. Diameter, 1J-3 In. Min. Int. Max. Min. Int. Max. Min. Int. Max. 15 Lift, in. . . . 0.02 0.04 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH 95,500 191,000 238,900 179,200 238,800 293,500 214,900 358,300 429,900 Lb. hr 65 131 163 122 163 203 146 245 293 25 Lift, in 0.02 0.04 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH 127,700 255,400 319,300 239,500 319,300 399,100 287,400 478,900 574,700 Lb. hr 87 174 218 164 218 272 196 326 392 50 Lift, in .... 0.02 0.04 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH 208,200 416,400 520,400 390,300 520,400 650,500 468,300 780,600 936,600 Lb. hr. . 142 284 354 266 354 444 320 532 639 75 Lift, in .... 0.02 0.04 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH 288,600 577,200 721,400 541,100 721,400 901,800 649,300 1,082,000 1,299,000 Lb. hr. . . . 197 393 492 369 492 615 443 738 886 100 Lift, in.... 0.02 0.04 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH 369,000 738,000 922,500 691,900 922,500 1,153,000 830,300 1,384,000 1,661,000 Lb. hr 252 503 629 472 629 786 566 944 1133 125 Lift, in. . . . 0.02 0.04 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH 449,400 898,900 1,124,000 842,700 1,124,000 1,404,000 1,011,000 1,685,000 2,022,000 Lb. hr. . 307 613 767 575 767 957 689 1149 1379 150 Lift, in .... 0.02 0.04 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH 529,900 1,060,000 1,325,000 993,500 1,325,000 1,656,000 1,192,000 1,987,000 2,384,000 Lb. hr. . 362 723 904 677 904 1129 813 1355 1625 175 Lift, in 0.02 0.04 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH 610,300 1,221,000 1,526,000 1,144,000 1,526,000 1,907,000 1,373,000 2,286,000 2,746,000 Lb. hr. . . . 416 833 1040 780 1040 1301 936 1561 1872 200 Lift, in. . . . 0.02 0.04 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH.. 690,700 1,381,000 1,727,000 1,295,000 1,727,000 2 158,000 1,554,000 2,590,000 3,108,000 Lb. hr 471 941 1178 883 1178 1472 1060 1766 2119 225 Lift, in 0.02 0.04 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH 771,100 1,542,000 1,928,000 1,446,000 1,928,000 2,410,000 1,735,000 2,892,000 3,470,000 Lb. hr. . . . 526 1052 1315 980 1315 1643 1183 1972 2366 250 Lift, in 0.02 0.04 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH 851,600 1,703,000 2 129,000 1,597,000 2 129 OCO 2 661,000 1 916 000 3,193,000 3,832,000 Lb. hr 581 1161 1451 1089 1451 1814 1307 2177 261S 275 Lift, in. . . . 0.02 O.C4 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH 932,000 1,864,000 2,330,000 ,748,000 2,330,000 2,913,000 2,097,000 3,495,000 4,194,000 Lb. hr. . . . 635 1271 1589 1192 1589 1986 1430 2383 286C 300 Lift, in 0.02 0.04 0.05 0.03 0.04 0.05 0.03 0.05 0.06 CH 1,024,000 2,048,000 2,531,000 ,898,000 2,531,000 3,164,000 2,278,000 3,797,000 4,556,000 Lb. hr 698 1397 1746 1294 1726 2157 1553 2589 3107 The Discharge capacity of a Flat Seat Valve of a given diameter with a given lift may be obtained by multiplyi e discharge capacity given in the Table for a 45 deg. bevrl seat valve of same diameter arid same lift, by 1.4. 70 TABLE 8 (CONTINUED) DISCHARGE CAPACITIES FOR DIRECT SPRING-LOADED POP SAFETY VALVES, WITH 45 DEC. BEVEL SEATS Gage Free., Lb. per Sq. In. Diameter, 2 In. Diameter, 2% In. Diameter, 3 In. Min. Int. Max. Min. Int. Max. Min. Int. Max. 15 Lift, in. . . . 0.04 0.06 0.07 0.04 0.06 0.08 0.05 0.08 0.10 CH 382,200 573,300 668,900 477,700 716,600 955,500 716,600 1,147,000 1,433,000 Lb. hr. . 261 391 456 326 488 651 489 782 977 25 Lift, in. . . . 0.04 0.06 0.07 0.04 0.06 0.08 0.05 0.08 0.10 CH 510,900 766,300 894,000 638,500 957,900 1,277,000 957,900 1,533,000 1,916,000 Lb. hr. . 349 523 610 435 653 871 653 1046 1307 Lift, in.... 0.04 0.06 0.07 0.04 O.G6 0.08 0.05 0.08 0.10 50 CH 832,600 1,249,000 1,457,000 1,041,000 1,561,000 2,081,000 1,561,000 2,498,000 3,122,000 Lb. hr. . 568 851 994 710 1064 1419 1064 1703 2129 75 Lift, in 0.04 0.06 0.07 0.04 0.06 0.08 0.05 0.08 0.10 CH 1,154,000 1,731,000 2,020,000 1,443,000 2,164,000 2,886,000 2,164,000 3,463,000 4,329,000 Lb. hr. . 787 1181 1377 984 1475 1968 1475 2361 2951 100 Lift, in 0.04 0.06 0.07 0.04 0.06 0.08 0.05 0.08 0.10 CH 1,476,000 2,214,000 2,583,000 1,845,000 2,768,000 3,690,000 2,768,000 4,428,000 5,535,000 Lb. hr. . . . 1007 1510 1761 1258 1887 2516 1887 3019 3774 125 Lift, in. . . . 0.04 0.06 0.07 0.04 0.06 0.08 0.05 0.08 0.10 CH 1,795,000 2,693,000 3,146,000 2,247,000 3,371,000 4.494,000 3,371,000 5,393,000 6,741,000 Lb. br. . 1224 1836 2145 1532 2299 3064 2299 3677 4596 150 Lift, in 0.04 0.06 0.07 0.04 0.06 0.08 0.05 0.08 0.10 CH 2,109,000 3,179,000 3,709,000 2,649,000 3,974,000 5,299,000 3,974,000 6,358,000 7,948,000 Lb. hr. . 1438 2158 2529 1806 2710 3613 2710 4335 5419 175 Lift, in.... 0.04 0.06 0.07 0.04 0.06 0.08 0.05 0.08 0.10 CH 2,441,000 3,662,000 4,272,000 3,051,000 4,577,000 6,103,000 4,577,000 7,323,000 9,154,000 Lb. hr. . 1664 2497 2913 2081 3121 4161 3121 4993 6242 200 Lift, in. . . . 0.04 0.06 0.07 0.04 0.06 0.08 0.05 0.08 0.10 CH 2,763,000 4,144,000 4,835,000 3,454,000 5,180,000 6,907,000 5,180,000 8,289,000 10,361,000 Lb.hr. . 18S4 2826 3296 2354 3532 4709 3532 5651 7064 225 Lift, in.... 0.04 0.06 0.07 0.04 0.06 0.08 0.05 0.08 0.10 CH 3,085,000 4,626,000 5,398,000 3,856,000 5,784,000 7,711,000 5,784,000 9,254,000 11,567,000 Lb. hr. . . . 2104 3154 3G80 2629 3944 5258 3944 6310 7890 250 Lift, in .... 0.04 0.06 0.07 0.04 0.06 0.08 0.05 0.08 0.10 CH 3,406,000 5,109,000 5,961,000 4,258,000 6,387,000 8,516,000 6,387,000 10,219,000 12,774,000 Lb. hr. . . . 2322 34S4 4004 2903 4355 5807 4355 6968 8708 275 Lift, in. . . . 0.04 0.06 0.07 0.04 0.06 0.08 0.05 0.08 0.10 CH 3,728,000 5,592,000 6,524,000 4,660,000 6,990,000 9,320,000 6,990,000 11,180,000 13,980,000 Lb.hr 2542 3813 4448 3177 4766 6355 4766 7620 9533 300 Lift, in.... 0.04 0.06 0.07 0.04 0.06 0.08 0.05 0.08 0.10 CH 4,050,000 6,075,000 7,087,000 5,062,000 7,593,000 10,124,000 7,593,000 12,149,000 15,186.000 Lb. hr. . . . 2762 4143 4832 3452 5177 6903 5177 82SO 10,358 The Discharge capacity of a Flat Seat Valve of a given diameter with a given lift may be obtained by multiply: the discharge capacity given in the Table for a 45 deg. bevel seat valve of same diameter and same lift, by 1.4. This table is concluded on the following pa 71 8 (CONCLUDED) DISCHARGE CAPACITIES FOR DIRECT SPRING-LOADED POP SAFETY VALVES, WITH 45 DEC. BEVEL SEATS age es., per In. Diameter, 33^ In. Diameter, 4 In. Diameter, 4> In. Min. Int. Max. Min. Int. Max. Min. Int. Max. Lift, in. ... 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 5 CH 1,003,000 1,505,000 1,839,000 1,338,000 1,911,000 2,293,000 1,720,000 2,365,000 2,795,00 ,b. hr 684 1026 1254 912 1303 1564 1173 1613 190 Lift, in. . . . 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 5 CH 1,341,000 2,012,000 2,459,000 1,788,000 2,554,000 3,065,000 2,299,000 3,161,000 3,736,00 Lb. hr 914 1372 1676 1219 1742 2090 1568 2156 254 jift, in. ... 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 CH 2,186,000 3,278,000 4,007,000 2,914,000 4,163,000 4,996,000 3,747,000 5,152,000 6,088,00 Lb. hr 1490 2235 2732 1987 2839 3406 2555 3513 415 Lift, in.... 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 5 CH 3,030,000 4,545,000 5,555,000 4,040,000 5,772,000 6,926,000 5,194,000 7,142,000 8,441,00 Lb. hr 2066 3099 3788 2754 3935 4722 3542 4870 575 .ift.in 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 >0 CH 3,875,000 5,812,000 7,103,000 5,166,000 7,380,000 8,856,000 6,642,000 9,133,000 10,793,00 Lb. hr 2642 3963 4843 3522 5032 6038 4529 6227 735 Ai t, in .... 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 55 CH 4,719,000 7,079,000 8,652,000 6,292,000 8,988,000 10,786,000 8,089,000 11,123,000 13,146,00 ,b. hr. . 3218 4826 5899 4290 6128 7354 5516 7583 896 Lift, in.... 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 >0 CH 5,564,000 8 345,000 10,199,000 7,418,000 10,597,000 12 717,000 9,537,000 13,114,000 15,498,00 Lb. hr 3794 5G90 6954 5058 72^t 8670 6503 8940 1056 75 Lift, in 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 CH 6,408,000 9,612,000 11,748,000 8,544,000 12,200,000 14,647,000 10,985,000 15,105,000 17,851,00 Lb. hr 4369 6553 8010 5824 8320 9984 7490 10298 1217 30 Lift, in. . . . 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 CH 7,253,000 10,879,000 13,296,000 9,670,000 13,814,000 16,580,000 12,433,000 17,095,000 20,204,OC Lb. hr . . . . 4946 7418 90C8 6503 9420 11305 8475 11655 1377 25 Lift, in 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 CH 8,097,000 12,146,000 14,845,000 10,796,000 15,423,000 18,507,000 13,881,000 19,086,000 22,556,OC Lb. hr 5521 8280 10120 7361 10514 12616 9465 13013 153S 50 Lift, in. . . . 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 CH 8,942,000 13,412,000 16,393,000 11,922,000 17,031,000 20,438,000 15,328,000 21,076,000 24.908.0C Lb. hr 6097 9143 11175 8130 11614 13938 10448 14366 1695 75 Lift, in. . . 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 CH 9,786,000 14,679,000 17,941,000 13,048,000 18,640,000 22,368,000 16,776,000 23,067,000 27.261.0C Lb. hr. . . 6672 10005 1223P 8801 12707 15248 11438 15728 185S 00 Lift, in ... 0.06 0.09 0.11 0.07 0.10 0.12 0.08 0.11 0.13 CH 10,630,000 15,946,000 19,489,000 14,174,000 20,249,000 24,298,000 18,224,000 25,058,OGC 29,614,0( Lb. hr. . . 724S 10875 13290 9668 13807 16568 12428 1708S 201' The Discharge capacity of a Flat Seat Valve of a given diameter with a given lift may be obtained by multiply!: discharge capacity given in the Table for a 45 deg. bevel seat valve of same diameter and same lift, by 1.4. 72 NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 73 275 .Safety valve capacity may be checked in any one of three different ways, and if found sufficient, additional capacity need not be provided : a By making an accumulation test, by shutting off all other steam discharge outlets from the boiler and forcing the fires to the maximum. The safety valve equipment shall be sufficient to prevent an excess pressure beyond six per cent as specified in Par. 270. I By measuring the maximum amount of fuel that can be burned and computing the corresponding evaporative ca- pacity upon the basis of the heating value of the fuel. See Appendix, Pars. 421 to 427. c By .determining the maximum evaporative capacity by measuring the feed water. The sum of the safety valve capacities marked on the valves, shall be equal to or greater than the maximum evaporative capacity of the boiler. 276 When two or more safety valves are used on a boiler, they may be either separate or twin valves made by mounting individual valves on Y-bases, or duplex, triplex or multiplex valves . having two or more valves in the same body casing. 277 The safety valve or valves shall be connected to the boiler independent of any other steam connection, and attached as close as possible to the boiler, without any unnecessary intervening pipe or fitting. Every safety valve shall be connected so as to stand in an up- right position, with spindle vertical, when possible. 278 Each safety valve shall have full sized direct connection to the boiler. Xo valve of any description shall be placed between the safety valve and the boiler, nor on the discharge pipe between the safety valve and the atmosphere. When a discharge pipe is used, it shall be not less than the full size of the valve, and shall be fitted with an open drain to prevent water from lodging in the upper part of the safety valve or in the pipe. 279 If a muffler is used on a safety valve it shall have sufficient outlet area to prevent back pressure from interfering with the proper operation and discharge capacity of the valve. The muffler plates or other devices shall be so constructed as to avoid any possibility of re- striction of the steam passages due to deposit. When an elbow is placed on a safety valve discharge pipe, it shall be located close to the safety valve outlet or the pipe shall be securely anchored and supported. All safety valve discharges shall be so located or piped as to be carried 74 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. clear from running boards or working platforms used in controlling the main stop valves of boilers or steam headers. 280 When a boiler is fitted with two or more safety valves on one connection, this connection to the boiler shall have a cross-sectional area not less than the combined area of all of the safety valves with which it connects. 281 ^Safety valves shall operate without chattering and shall be set and adjusted as follows : To close after blowing down not more than 4 Ib. on boilers carrying an allowed pressure less than 100 Ib. per sq. in. gage. To close after blowing down not more than 6 Ib. on boilers carrying pressures between 100 and 200 Ib. per sq. in. gage inclusive. To close after blowing down not more than 8 Ib. on boilers carrying over 200 Ib. per sq. in. gage. 282 Each safety valve used on a boiler shall have a substantial lifting device, and shall have the spindle so attached that the valve disc can be lifted from its seat a distance not less than one-tenth of the nominal diameter of the valve, when there is no pressure on the boiler. 283 The seats and discs of safety valves shall be of non-ferrous material. 284 Springs used in safety valves shall not show a permanent set exceeding 1/3,2 in. ten minutes after being released from a cold com- pression test closing the spring solid. 285 The spring in a safety valve shall not be used for any pressure more than 10 per cent above or below that for which it was designed. 286 A safety valve over 3-in. size, used for pressures greater than 15 Ib. per sq. in. gage, shall have a flanged inlet connection. The dimensions of the flanges shall conform to the American standard given in Tables 15 and 16 of the Appendix. 287 When the letters A 8 M E Std are plainly stamped or cast on the valve body this shall be a guarantee by the manufacturer that the valve conforms with the details of construction herein specified. 288 Every superheater shall have one or more safety valves near the outlet. The discharge capacity of the safety valve or valves on an attached superheater may be included in determining the number and sizes of the safety valves for the boiler, provided there are no in- tervening valves between the superheater safety valve and the boiler. 289 Every safety valve used on a superheater, discharging super- heated steam, shall have a steel body with a flanged inlet connection, NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 75 and shall have the seat and disc of nickel composition or equivalent material, and the spring fully exposed outside of the valve casing so that it shall be protected from contact with the escaping steam. 290 Every boiler shall have proper outlet connections for the required safety valve or valves, independent of any other steam outlet connection or of any internal pipe in the steam space of the boiler, the area of opening to be at least equal to the aggregate area of all of the safety valves to be attached thereto. WATER AND STEAM GAGES 291 Water Glasses and Gage Cocks. Each boiler shall have at least one water glass, the lowest visible part of which shall be not less than 2 in. above the lowest permissible water level. 292 No water glass connection shall be fitted with an automatic shut-off valve. ,293 When shut-off s are used on the connections to a water column, they shall be either outside screw and yoke type gate valves or stop cocks with levers permanently fastened thereto, and such valves or cocks shall be locked or sealed open. 294 Each boiler shall have three or more gage cocks, located within the range of the visible length of the water glass, except when such boiler has two water glasses with independent connections to the boiler and located on the same horizontal line and not less than 2 ft. apart. 395 Xo outlet connections, except for damper regulator, feed- water regulator, drains or steam gages, shall be placed on the pipes connecting a w r ater column to a boiler. 296 Steam Gages. Each boiler shall have a steam gage con- nected to the steam space or to the water column or its steam connec- tion. The steam gage shall be connected to a syphon or equivalent device of sufficient capacity to keep the gage tube filled with water and so arranged that the gage cannot be shut off from the boiler except by a cock placed near the gage and provided with a tee or lever handle arranged to be parallel to the pipe in which it is located when the cock is open. Connections to gages shall be of brass, copper or bronze composition. 297 The dial of the steam gage shall be graduated to not less than iy 2 times the maximum allowable working pressure on the boiler. 298 Each boiler shall be provided with a ^-in. pipe size valved 76 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. connection for attaching a test gage when the boiler is in service, so that the accuracy of the boiler steam gage can be ascertained. FITTINGS AND APPLIANCES 299 Nozzles and Fittings. All fittings shall conform to the American 'Standards given in Tables 15 or 16 of the Appendix. Where the maximum allowable working pressure is less than 125 Ib. per sq. in., Table 15 shall be used and where higher, Table 16. 300 The minimum number of threads that a pipe or fitting shall screw into a tapped hole shall correspond to the numerical values given for number of threads in Table 7. 301 Stop Valves. Each steam discharge outlet over 2 in. in di- ameter, except safety valve and superheater connections, shall be fitted with a stop valve or valves of the outside screw and yoke type, located as near the boiler <;s practicable. 302 The main stop valves of boilers shall be extra heavy when the maximum allowable working pressure exceeds 125 Ib. per sq. in. The fittings between the boiler and such valve or valves shall be extra heavy, as specified in Table 16 of the Appendix. 303 When two or more boilers are connected to a common steam main, two stop valves, with an ample free blow drain between them, shall be placed in the steam connection between each boiler and the steam main. The discharge of this drain valve must be visible to the operator while manipulating the valve. The stop valves shall consist preferably of one automatic non-return valve (set next the boiler) and a second valve of the outside screw and yoke type; or, two valves of the outside screw and yoke type may be used. 304 When a stop valve is so located that water can accumulate, ample drains shall be provided. 305 Steam Mains. Provisions shall be made for the expansion and contraction of steam mains connected to boilers, by providing substantial anchorage at suitable points, so that there shall be no undue strain transmitted to the boiler. >Steam reservoirs shall be used on steam mains when heavy pulsations of the steam currents cause vibration of the boiler shell plates. 306 Each superheater shall be fitted with a drain. 307 Blow-off Piping. The size of a surface blow-off pipe shall not exceed 1% in., and it shall be carried through the shell or head with a brass or steel boiler bushing. NEW INSTALLATIONS, PART I, SECTION I, POWER BOILERS 77 308 Each boiler shall have a bottom blow-off pipe, fitted with a valve or cock, in direct connection with the lowest water space prac- ticable ; the minimum size of pipe and fittings shall be 1 in. and the maximum size shall be 2*/ 2 in. Globe valves shall not be used on such connections. 309 A bottom blow-off cock shall have the plug held in place by a guard or gland. The end of the plug shall be distinctly marked in line with the passage. 310 The blow-off pipe or pipes shall be extra heavy from boiler to valve or valves, and shall run full size without reducers or bushings. All fittings between the boiler and valves shall be of steel. 311 When the maximum allowable working pressure exceeds 12<5 Ib. per sq. in., the bottom blow-off pipe shall have two valves, or a valve and a cock, and such valves, or valve and cock, shall be extra heavy, except that on a boiler having multiple blow-off pipes, a single master valve may be placed on the common blow-off pipe from the boiler, in which case only one valve on each individual blow-off is required. 312 A bottom blow-off pipe when exposed to direct furnace heat shall be protected by fire-brick, a substantial cast-iron removable sleeve or a covering of non-conducting material. 313 An opening in the boiler setting for a blow-off pipe shall be arranged to provide for free expansion and contraction. 314 Feed Piping. The feed pipe of a boiler shall have an open end or ends. Wherever globe valves are used on feed piping, the inlet shall be under the disc of the valve. 315 The feedwater shall discharge at about three-fifths the length of a horizontal return tubular boiler from the front head (except a horizontal return tubular boiler equipped with an auxiliary feedwater heating and circulating device), above the central rows of tubes, when the diameter of the boiler exceeds 36 in. The feed pipe shall be car- ried through the head or shell near the front end with a brass or steel boiler bushing, and securely fastened inside the shell above the tubes. 316 Feedwater shall not discharge in a boiler close to riveted joints in the shell or to furnace sheets. 317 The feed pipe shall be provided with a check valve near the boiler and a valve or cock between the check valve and the boiler, and when two or more boilers are fed from a common source, there shall also be a globe valve on the branch to each boiler, between the check valve and the source of supply. 78 REPORT O? JCOILER CODE COMMITTEE, AM.SOC.M.E. 318 When a pump, inspirator or injector is required to supply feedwater to a boiler plant of over 50 h. p., more than one such appliance shall be provided. 3,19 Lamplircy Fronts. Each boiler fitted with a Lamphrey boiler furnace mouth protector, or similar appliance, having valves on the pipes connecting them to the boiler, shall have these valves locked or sealed open. Such valves when used, shall be of the straight- way type. 320 Water Column Pipes. The minimum size of pipes connect- ing the water column to a boiler shall be 1 in. Water-glass fittings or gage cocks may be connected direct to the boiler. 3.21 The water connections to the water column of a boiler shall be of brass and shall be provided with a cross to facilitate cleaning. Either the water column or this connection shall be fitted with a drain cock or drain valve with a suitable connection to the ashpit, or other safe point of waste. The water column blow-off pipe shall be at least % i n - &2& The steam connection to the water column of a horizontal return tubular boiler shall be taken from the top of the shell or the upper part of the head ; the water connection shall be taken from a point not less than 6 in. below the center line of the shell. SETTING 3(23 Methods of Support. A horizontal return tubular boiler over 78-in. in diameter shall be supported from steel lugs by the out- side suspension type of setting, independent of the boiler side walls. The lugs shall be so designed that the load is properly distributed between the rivets attaching them to the shell and so that not more than two of these rivets come in the same longitudinal line on each lug. The distance girthwise of the boiler from the centers of the bottom rivets to the centers of the top rivets attaching the lugs shall be not less than 12 in. The other rivets used shall be spaced evenly between these points. If more than four lugs are used they shall be set in four pairs. 3i24 A horizontal return tubular boiler over 5-i in., and up to and including 78 in. in diameter, shall be supported by the outside suspension type of setting, or at four points by not less than eight steel or cast-iron brackets set in pairs. A horizontal return tubular boiler up to and including 54 in. in diameter shall be supported by the outside suspension type of setting, or by not less than two steel or cast-iron brackets on each side. NEW INSTALLATIONS, PART I, SECTION I, TOWER BOILERS 79 325 Lugs or brackets, when used to support boilers, shall be properly fitted to the surfaces to which they are attached. The shearing stress on the rivets used for attaching the lugs or brackets shall not exceed 8 per cent of the strength given in Par. 1G. 326 Wet-bottom stationary boilers shall have a space of not less than 12 in. between the bottom of the boiler and the floor line, with access for inspection. 3,27 Access and Firing Doors. The minimum size of an access door to be placed in a boiler setting shall be 12 X 16 in. or equivalent area, 11 in. to be the least dimension in any case. 328 A water tube boiler which is fired by hand shall have firing door or doors of the inward opening type unless such doors are pro- vided with substantial latching devices to prevent them from being blown open by pressure on the furnace side. HYDROSTATIC TESTS 329 Hydrostatic Pressure Tests. After a boiler has been com- pleted, it shall be subjected to a hydrostatic test of one and one-half times the maximum allowable working pressure. The' pressure shall be under proper control so that in no case shall the required test pressure be exceeded by more than 6 per cent. 330 During a hydrostatic test, the safety valve or valves shall be removed or each valve disc shall be held to its seat by means of a testing clanip and not by screwing down the compression screw upon the spring. STAMPING 331 Stamping of Boilers. In laying out shell plates, furnace sheets and heads in the boiler shop, care shall be taken to leave at least one of the stamps, specified in Par. 36 of these Rules, so located as to be plainly visible when the boiler is completed; except that the tube sheets of a vertical fire-tube boiler and butt straps shall have at least a portion of such stamps visible sufficient for identification when the boiler is completed. 332 Each boiler shall conform in every detail to these Rules, and shall be distinctly stamped with the symbol as shown in Fig. 19, de- noting that the boiler was constructed in accordance therewith. Each boiler shall also be stamped by the builder with a serial number and 80 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. with the builder's name either in full or abbreviated, as indicated in Fig. 20. The height of the letters and figures used in stamping shall be not less than 14 in. and this stamp shall be placed directly below or alongside The American Society of Mechanical Engineers' stamp. (Name of State) STD (Number of Boiler) f (Name of Builder) FIG. 19 OFFICIAL SYMBOL FOR STAMP FIG. 20 FORM OF STAMP PROPOSED TO DENOTE THE AMERICAN So- FOR THE BOILER MANUFACTURER CIETY OF MECHANICAL ENGI- NEERS UNIFORM STANDARD 33.3 Location of Stamps. The location of stamps shall be as follows : a On horizontal return tubular boilers on the front head, above the central rows of tubes. & On horizontal flue boilers on the front head, above the flues. c On traction, portable or stationary boilers of the locomo- tive type or ,Star water-tube boilers on the furnace end, above the handhole. d On vertical fire, tube and vertical submerged tube boilers on the shell above the fire door. e On water-tube boilers, Babcock & Wilcox, (Stirling, Heine and Eobb-Mumford standard types on a head above the manhole opening, preferably on the flanging of the manhole opening. / On vertical boilers, Climax or Hazleton type on the top head. g On Cahall or Wickes vertical water tube boilers on the upper drum, above the manhole opening. h On Scotch marine boilers on the front head, above the center or right-Hand furnace. i On Economic boilers on the front head, above the central row of tubes. j For other types and new designs in a conspicuous loca- tion. 334 The American .Society of Mechanical Engineers' standard stamp and the boiler builder's stamps shall not be covered by insulat- ing or other material. PART I SECTION II BOILERS USED EXCLUSIVELY FOR LOW PRESSURE STEAM AND HOT WATER HEATING AND HOT WATER SUPPLY (THIS DOES NOT APPLY TO ECONOMIZERS OR FEED WATER HEATERS.) BOILER MATERIALS 335 The Rules for power boilers shall apply : a To all steel plate hot-water boilers over 60 in. in diameter, I To all steel plate hot-water boilers where the grate area ex- ceeds 10 sq. ft. and the maximum allowable working pres- sure exceeds 50 Ib. per sq. in. c Under other conditions, the following rules shall apply. 336 Specifications are given in these Rules, Pars. 23 to 178, for the important materials used in the construction of boilers, and where given., the materials shall conform thereto. 337 Flange steel may be used entirely for the construction of steam heating boilers covered in this section, but in no case shall steel of less than % in. in thickness, nor tube sheets or heads of less than 5/16 in. in thickness be used. MAXIMUM ALLOWABLE WORKING PRESSURE 338 The maximum allowable working pressure shall not exceed 15 Ib. per sq. in. on a boiler built under these Rules to be used ex- clusively for low pressure steam heating. 339 A boiler to be used exclusively for low-pressure steam heat- ing, may be constructed of cast-iron, or of cast-iron excepting con- necting nipples and bolts, or wholly of steel or wrought-iron, or of steel and partially cast-iron, or of steel or wrought-iron with cast-iron mud rings, door frames and manhole flanges. 340 All steel plate, hot-water and steam-heating boilers shall have a factor of safety of not less than 5. 81 82 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. BOILER JOINTS 341 Longitudinal lap joints will be allowed on boilers to be used exclusively for low pressure steam heating, when the maximum allowable working pressure does not exceed 15 Ib. per sq. in., and the diameter of the boiler shell does not exceed 60 in. 342 The longitudinal joints of a horizontal return tubular boiler if of the lap type, shall be not over 1 2 ft. in length. 343 In a hot-water boiler to be used excusively for heating build- ings or hot water supply when the diameter does not exceed 60 in. and the grate area does not exceed 10 sq. ft., longitudinal lap joints will be allowed. When the grate area exceeds 10 sq. ft. and the diameter of the boiler does not exceed 60 in. longitudinal lap joints will be allowed providing the maximum allowable working pressure does not exceed 50 Ib. per sq. in. 344 Protection of Joints. When a boiler is built wholly or partially of steel and is used exclusively for low pressure steam heat- ing, or when a hot-water boiler is used exclusively for heating build- ings or for hot-water supply, it shall not be necessary to water jacket the rivets in the fire-box where one end of each rivet is exposed to the fire or direct radiant heat from the fire, provided any one of the following conditions is fulfilled : a Where the ends of the rivets away from the fire are pro- tected by means of natural drafts of cold air induced in the regular operation of the boiler ; 1} Where the ends of the rivets away from the fire are in the open air ; c Where the rivets are protected by the usual charges of fresh fuel, which is not burned in contact with the rivets. WASHOUT HOLES 345 A boiler used for hot-water supply shall be provided with washout holes for the removal of any sediment that may accumulate therein. BOILER OPENINGS 346 Flanged Connections. Openings in boilers having flanged connections shall have the flanges conform to the American Standard NEW INSTALLATIONS, PART I, SECTION II, HEATING BOILERS 83 given in Tables 15 or 16 of the Appendix, for the corresponding pipe size, and shall have the corresponding drilling for bolts or studs. SAFETY VALVES 347 Outlet Connections for Safety and Water Relief Valves. Every boiler shall have proper outlet connections for the required safety, or water relief valve or valves, independent of any other con- nection outside of the boiler or any internal pipe in the boiler, the area of the opening to be at least equal to the aggregate area of all of the safety valves with which it connects. A screwed connection may be used for attaching a safety valve to a heating boiler. This rule applies to all sizes of safety valves. :348 Safety Valves. Each steam boiler shall be provided with one or more safety valves of the spring-pop type which cannot be adjusted to a higher pressure than 15 Ib. per sq. in. 349 Water Relief Valves. Each hot-water boiler shall be pro- vided with one or more water relief valves with open discharges hav- ing outlets in plain sight. 350 A hot-water boiler built for a maximum allowable working pressure of 30 Ib. per sq. in. and used exclusively for heating build- ings, or for hot-water supply, shall be provided with a water relief valve or valves, which cannot be adjusted for a pressure in excess of 30 Ib. per sq. in. 351 No safety or water relief valve shall be smaller than 1 in. nor greater than 4^ in. nominal size. 352' When two or more safety or water relief valves are used on a boiler they may be single or twin valves. 353 Safety or water relief valves shall be connected to boilers independent of other connections and be attached directly or as close as possible to the boiler, without any intervening pipe or fittings, except the Y-base forming a part of the twin valve or the shortest possible connection. A safety or water relief valve shall not be con- nected to an internal pipe in the boiler. .Safety valves shall be con- nected so as to stand upright, with the spindle vertical, when possible. 354 Xo shut-off of any description shall be placed between the safety cr water relief valves and boilers, nor on discharge pipes be- tween them and the atmosphere. 355 When a discharge pipe is used its area shall be not less than the area of the valve or aggregate area of the valves with which it 84 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. connects, and the discharge pipe shall be fitted with an open drain to prevent water from lodging in the upper part of the valve or in the pipe. When an elbow is placed on a safety or water relief valve discharge pipe, it shall be located close to the valve outlet or the pipe shall be securely anchored and supported. The safety or water relief valves shall be so located and piped that there will be no danger of scalding attendants. 356 Each safety valve used on a steam heating boiler shall have a substantial lifting device which shall be so connected to the disc that the latter can be lifted from its seat a distance of not less than TABLE 9 ALLOWABLE SIZES OF SAFETY VALVES FOR HEATING BOILERS Water Evaporated per Sq. Ft. of Grate Surface per 75 100 160 160 200 240 Hr., Lb. Maximum allowable Working Pressure, Zero to Over 25 to Over 50 to Over 100 to Over 150 to Over 200 T K Lb. per Sq. In. 25 Lb. 50 Lb. 100 Lb. 150 Lb. 200 Lb. LiD. Diameter Area of Valve, of Valve, Area of Grate, Sq. Ft. In. Sq. In. 1 0.7854 2.00 2.50 2.75 3.25 3.5 3.75 1M 1.2272 3.25 4.00 4.25 5.00 5.5 5.75 IH 1.7671 4.50 5.50 6.00 7.25 8.0 8.50 2 3.1416 8.00 9.75 10.75 13.00 14.0 15.00 2y 2 4.9087 12.50 15.00 16.50 20.00 22.0 23.00 3 7.0686 17.75 21.50 24.00 29.00 31.5 33.25 3 1 A 9.6211 24.00 29.50 32.50 39.50 43.0 45.25 4 12.5660 31.50 38.25 42.50 51 . 50 56.0 59.00 4K 15.9040 40.00 48.50 53.50 65.00 71.0 74.25 one-tenth of the nominal diameter of the seat when there is no pres- sure on the boiler. A relief valve used on a hot-water heating boiler need not have a lifting device. 357 Every safety valve or water relief valve shall have plainly stamped on the body or cast thereon the manufacturer's name or trade mark and the pressure at which it is set to blow. The seats and discs of safety or water relief valves shall be made of non-ferrous material. 358 The minimum size of safety or water relief valve or valves for each boiler shall be governed by the grate area of the boiler, as shown by Table 9. NEW INSTALLATIONS, PART I, SECTION II, HEATING BOILERS 85 When the conditions exceed those on which Table 9 is based, the following formula for bevel and flat seated valves shall be used : in which A area of direct spring-loaded safety valve per square foot of grate surface, sq. in. TF weight of water evaporated per square foot of grate sur- face per second, Ib. P = pressure (absolute) at which the safety valve is set to blow, Ib. per sq. in. 359 Double Grate Down Draft Boilers. In determining the number and size of safety valves or water relief valves the grate area shall equal the area of the upper grate plus one-half of the area of the lower grate. 360 Boilers Fired With Oil or Gas. In determining the number and size of safety or water relief valve or valves for a boiler using gas or liquid fuel, 15 sq. ft. of heating surface shall be equivalent to one square foot of grate area. If the size of grate for use of coal is evi- dent from the boiler design, such size may be the basis for the de- termination of the safety valve capacity. STEAM AXD WATER GAGES 361 Steam Gages. Each steam boiler shall have a steam gage connected to the steam space or to the water column or its steam connection. The steam gage shall be connected to a syphon or equivalent device of sufficient capacity to keep the gage tube filled with water and so arranged that the gage cannot be shut off from the boiler except by a cock placed near the gage and provided with a tee or lever handle arranged to be parallel to the pipe in which it is lo- cated when the cock is open. Connections to gages shall be of brass, copper or bronze composition. The dial of a steam gage for a steam heating boiler shall be graduated to not less than 30 Ib. 36$ Pressure or Altitude Gages. Each Iwt-ivater boiler shall have a gage connected in such a manner that it cannot be shut off from the boiler except by a cock with tee or lever handle, placed on the pipe near the gage. The handle of the cock shall be parallel to the pipe in which it is located when the cock is open. Connections to gages shall be made of brass, copper or bronze composition. The dial of 86 EEPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. the pressure or altitude gage shall be graduated to not less than iy 2 times the maximum allowable working pressure. 363 Thermometers. Each liot-water boiler shall have a ther- mometer so located and connected that it shall be easily readable when observing the water pressure or altitude. The thermometer shall be so located that it shall at all times indicate the temperature in deg. f ahr., of the water in the boiler. FITTINGS AND APPLIANCES 364 Bottom Blow-off Pipes. Each boiler shall have a blow-off pipe, fitted with a valve or cock, in direct connection with the lowest water space practicable. 365 Damper Regulators. When a pressure damper regulator is used, the boiler pressure pipe shall be connected to the steam space of the boiler. 366 Water Glasses. Each steam boiler shall have one or more water glasses. 367 Gage Cocks. Each steam boiler shall have two or more gage cocks located within the range of the visible length of the water glass. 36/8 Water Column Pipes. The minimum size of pipes connect- ing the water column of a boiler shall be 1 in. Water-glass fittings or gage cocks may be connected direct to the boiler. The steam con- nection to the water column of a horizontal return tubular boiler shall be taken from the top of shell or the upper part of the head ; the water connection shall be taken from a point not less than 6 in. below the center line of the shell. No connections, except for damper regu- lator, drains or steam gages, shall be placed on the pipes connecting a water column to a boiler. METHODS OF SETTING 369 Wet-bottom steel plate boilers shall have a space of not less than 12 in. between the bottom of the boiler and the floor line with access for inspection. 370 Access Doors. The minimum size of access door used in boiler settings shall be 12 X 16 in. or equivalent area, the least dimension being 11 in. .371 The longitudinal joints of a horizontal return tubular boiler shall be located above the fire-line. NEW INSTALLATIONS, PART I, SECTION II, HEATING BOILERS 87 HYDROSTATIC TESTS 372 .4 shop test of 60 Ib. per sq. in. hydrostatic pressure shall be applied to steel or cast-iron boilers or to the sections of cast-iron boilers which are used exclusively for low pressure steam heating. 373 IIo t-water boilers for a maximum allowable working pressure not exceeding 30 Ib. per sq. in. used exclusively for heating buildings or for hot-water supply, when constructed of cast-iron, or of cast-iron excepting the connecting nipples and bolts, shall be subjected to a shop test of 60 Ib. per sq. in. hydrostatic pressure applied to the boiler or the sections thereof. 37-i A maximum allowable working pressure in excess of 30 Ib. per sq. in. will be allowed on a hot-water boiler constructed of cast- iron, or of cast-iron excepting the connecting nipples and bolts, used exclusively for heating buildings or for hot-water supply, provided such boilers or their sections have been subjected to a shop hydrostatic test of two and one-half times the actual working pressure. 375 Individual shop inspection shall be required only for boilers which come under the rules for power boilers. (STAMPING 376 Each plate of a completed boiler shall show a sufficient portion of the plate maker's stamp for identification. 377 Name. All boilers referred to in this section shall be plainly and permanently marked with the manufacturer's name and the maxi- mum allowable working pressure. PART II EXISTING INSTALLATIONS MAXIMUM ALLOWABLE WORKING PRESSURE 378 The maximum allowable working pressure on the shell of a boiler or drum shall be determined by the strength of the weakest course, computed from the thickness of the plate, the tensile strength of the plate, the efficiency of the longitudinal joint, the inside diame- ter of the course and the factor of safety allowed by these Rules. = maxinmm allowable working pressure, Ib. per sq. in. where T8 = ultimate tensile strength of shell plates, Ib. per sq. in. t = thickness of shell plate, in weakest course, in. E =: efficiency of longitudinal joint, method of determining which is given in Par. 181, of these Rules R = inside radius of the weakest course of the shell or drum, in. FS = factor of safety allowed by these Rules *379 Boilers of Butt and Double strap construction, in ser- vice for a period of one year after these Orders become effective, shall be operated with a factor of safety of at least four (4) by the formula, Par. 378. Five years after these Orders become effective, the factor of safety shall be at least four and five-tenths (4.5). In no case shall the maximum allowable working pressure on old boilers be increased, unless they are being operated at a lesser pressure than would be allowable for new boilers, in which case the changed pressure shall not exceed that allowable for new boilers of the same construction. *380 (a) The lowest factor of safety used for boilers, the shells or drums of which are exposed to the direct products of combustion, and the longitudinal joints of which are of lap riveted construction, shall be as follows : 4i for boilers not over five (5) years old. 4 for boilers over five (5) and not over ten (10) years old. 4f for boilers over ten (10) and not over fifteen (15) years old. 5 for boilers over fifteen (15) and not over twenty (20) years old. For each five (5) years thereafter the factor of safety shall be increased by a further one-half (J) point, unless conditions are such as to warrant a continuance of a factor of safety of five (5), and provided further that within one (1) year after the date these "Indicates changes by the Industrial Accident Commission of the State of California. REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. Orders go into effect, a factor of safety of four (4) may be used on boilers not over ten (10) years old, where conditions warrant. (6) The lowest factor of safety for boilers, the shells or drums of which are NOT exposed to the direct products of combustion, and the longitudinal joints of which are of lap riveted construction, shall be as follows : 4 for boilers not over ten (10) years old. 4J for boilers over ten (10) and not over fifteen (15) years old. 41 for boilers over fifteen (15) and not over twenty (20) years old. 5 for boilers over twenty (20) years old. For each five (5) years thereafter, the factor of safety shall be increased by a further one-half (J) point. 381 Second-hand boilers, by which are meant boilers where both the ownership and location are changed, shall have a factor of safety of at least 5J, by the formula Par. 378, one year after these Rules become effective, unless constructed in accordance with the Rules contained in Part I, when the factor shall be at least 5. 382 Cast-Iron Headers and Mud Drums. The maximum allow- able working pressure on a water tube boiler, the tubes of which are secured to cast-iron or malleable iron headers, or which have cast- iron mud drums, shall not exceed 160 Ib. per sq. in. 383 Steam Heating Boilers. The maximum allowable working pressure shall not exceed 15 Ib. per sq. in. on a boiler used exclu- sively for low pressure steam heating. 384 No pressure shall be allowed on a boiler on which a crack is discovered along the longitudinal riveted joint. STRENGTH OP MATERIALS 385 Tensile Strength. "When the tensile strength of steel or wrought-iron shell plates is not known, it shall be taken as 55.000 Ib. per sq. in. for steel and 45,000 Ib. for wrought-iron. 386 Strength of Rivets in Shear. In computing the ultimate strength of rivets in shear, the following values in pounds per square inch of the cross-sectional area of the rivet shank shall be uspd : Iron rivets in single shear 38.000 Iron rivets in double shear 76,000 Steel rivets in single shear 44,000 Steel rivets in double shear 88,000 The cross-sectional area shall be that of the rivet shank after driving. 387 Crushing Strength oj < el. The resistance to crush- ing of mild steel shall be taken at 95,000 Ib. per sq. in. of cross- sectional area. EXISTING INSTALLATIONS. PART H TABLE 10 SIZES OF RIVETS BASED ON PLATE THICKNESS Tiiickness of plate \f JL ^ 14* Diameter of rivet after driving H' W H' ' H' If H* Thickness of plate. A" H' M* Jt 5 ' Diameter of rivet after driving H* H H* 1 JF* I JL *388 Rivets. When the diameter of the rivet holes in the longitudinal joints of a boiler is not known, the diameter and cross- sectional area of rivets after driving may be ascertained from Table 10 for boilers built in an Eastern shop, or by cutting out one rivet in the body of the joint. For boilers built on the Pacific Coast, the rivets are to be assumed as three-fourths (%) of an inch before driving and thirteen- sixteenths ( 1 %e) f an inch after driving in five-sixteenths (%s) inch and eleven-thirty-seconds ( 1 %2) inch plate. SAFETY VALVES FOR POWER BOILERS 389 The safety valve capacity of each boiler shall be such that the safety valve or valves will discharge all the steam that can be generated by the boiler without allowing the pressure to rise more than 6 per cent above the maximum allowable working pressure, or more than 6 per cent above the highest pressure to which any valve is set. 390 One or more safety valves on every boiler shall be set at or below the maximum allowable working pressure. The remaining valves may be set within a range of 3 per cent above the maximum allowable working pressure, but the range of setting of all of the valves on a boiler shall not exceed 10 per cent of the highest pressure to which any valve is set. 391 Safety valve capacity may be checked in any one of three different ways, and if found sufficient, additional capacity need not be provided : a By making an accumulation test, by shutting off all other - am discharge outlets from the boiler and forcing the fires to the maximum. The safety valve equipment shall be sufficient to prevent an excess pressure beyond 6 per cent as specified in Par. 389. b By measuring the maximum amount of fuel that can be burned and computing the corresponding evaporative Indicates changes by the Industrial Accident Commission of the State of California. 92 REPORT OP BOILER CODE COMMITTEE, AM.SOC.M.E. capacity upon the basis of the heating value of the fuel. See Appendix, Pars. 421 to 427. c By determining the maximum evaporative capacity by measuring the feed water. The sum of the safety valve capacities shall be equal to or greater than the maximum evaporative capacity of the boiler. 392 In case either of the methods outlined in sections Z> or c of Par. 391 is employed, the safety valve capacities shall be taken at the maximum values given in Table 8 for spring loaded pop safety valves, or 0.66 times the maximum values given in Table 8, for lever safety valves. 393 When additional valve capacity is required, any valves added shall conform to the requirements in Part I of these Rules. 394 No valve of any description shall be placed between the safety valve and the boiler, nor on the discharge pipe between the safety valve and the atmosphere. When a discharge pipe is used, it shall be not less than the full size of the valve, and the discharge pipe shall be fitted with an open drain to prevent water lodging in the upper part of the safety valve or in the pipe. If a muffler is used on a safety valve it shall have sufficient outlet area to prevent back pressure from interfering with the proper operation and discharge capacity of the valve. The muffler plates or other devices shall be so constructed as to avoid any possibility of restriction of the steam passages due to deposit. When an elbow is placed on a safety valve discharge pipe, it shall be located close to the safety valve outlet or the pipe shall be securely anchored and supported. All safety valve discharges shall be so located or piped as to be carried clear from running boards or working platforms used in controlling the main stop valves of boilers or steam headers. FITTINGS AND APPLIANCES 395 Water Glasses and Gage Cocks. Each steam boiler shall have at least one water glass, the lowest visible part of which shall be not less than 2 in. above the lowest permissible water level. 396 Each boiler shall have three or more gage cocks, located within the range of the visible length of the water glass, when the maximum allowable working pressure exceeds 15 Ib. per sq. in., except when such boiler has two water glasses with independent con- nections to the boiler, located on the same horizontal line and not less than two (2) feet apart. EXISTING INSTALLATIONS, PART II Exception should be made where the height of the seg- ment above the tubes on the boiler does not exceed twelve (12) inches; in which case, at least two (2) gage cocks located within the visible range of the water glass must be used. 397 No outlet connections, except for damper regulator, feed- water regulator, drains or steam gages, shall be placed on the pipes connecting a water column to a power boiler. 398 Steam Gages. Each steam boiler shall have a steam gage connected to the steam space or to the water column or to its steam connection. The steam gage shall be connected to a syphon or equivalent device of sufficient capacity to keep the gage tube filled with water and so arranged that the gage cannot be shut off from the boiler except by a cock placed near the gage and provided with a tee or lever handle arranged to be parallel to the pipe in which it is located when the cock is open. Connections to gages shall be of brass, copper or bronze composition. 39Sa Each boiler shall be provided with a one-quarter (J") inch pipe size valved connection for attaching a test gage when the boiler is in service, so that the accuracy of the boiler steam gage can be ascertained. 399 Stop Valves. Each steam outlet from a power boiler (except safety valve connections) shall be fitted with a stop valve located as close as practicable to the boiler. 400 When a stop valve is so located that water can accumulate, ample drains shall be provided. 401 Bottom Blow-Off Pipes. Each boiler shall have a blow-off pipe fitted with a valve or cock, in direct connection with the lowest water space practicable. 402 When the maximum allowable working pressure exceeds 125 Ib. per sq. in., the blow-off pipe shall be extra heavy from boiler to valve or valves, and shall run full size without reducers or bush- ings. All fittings between the boiler and valve shall be steel, extra heavy malleable iron or extra heavy cast-iron. 403 When the maximum allowable working pressure exceeds 125 Ib. per sq. in., each bottom blow-off pipe shall be fitted with an extra heavy valve or cock. Preferably two (2) valves, or a valve and a cock should be used on each blow-off, in which case such valves, or valve and cock, shall be extra heavy. *404 The blow-off pipe or boiler rest, or both, when exposed to direct action of products of combustion, shall be properly protected "Indicates changes by the Industrial Accident Commission of the State of California. 94 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. by a sleeve, asbestos rope, or other suitable material, or a protecting pier of brick built in ' ' V ' ' shape, or other pier with corner pointing toward and against path of flame. 405 An opening in the boiler setting for a blow-off pipe shall be arranged to provide for free expansion and contraction. 406 Feed Piping. 1 The feed pipe of a steam boiler operated at more than 15 Ib. per sq. in. maximum allowable working pressure, shall be provided with a check valve near the boiler and a valve or cock between the check valve and the boiler, and when two or more boilers are fed from a common source, there shall also be a globe valve on the branch to each boiler, between the check valve and the source of supply. When a globe valve is used on a feed pipe, the inlet shall be under the disc of the valve. *406a The main feed in boilers operated at more than fifteen (15) Ibs. per sq. in. maximum allowable working pressure, shall not enter the boiler through the blow-off. *406& When a pump, inspirator, or injector is required to sup- ply feed water to a boiler of over 50 hp., more than one such mechanical appliance shall be provided. 407 Lamphrey Fronts. Each boiler fitted with a Lamphrey boiler furnace mouth protector, or similar appliance, having valves on the pipes connecting them to the boiler, shall have these valves locked or sealed open. Such valves, when used, shall be of the straightway type. HYDROSTATIC PRESSURE TESTS. *408 When a hydrostatic test is applied the required test pres- sure shall be not more than one and one-half (1^) times the maxi- mum allowable working pressure, and not less than the maximum allowable working pressure. The pressure shall be under proper control so that in no case shall the required test pressure be exceeded by more than two (2) per cent. No person other than an inspector holding a certificate of competency shall apply a hydrostatic test on any boiler in excess of the allowable working pressure as set forth in the certificate of inspection. 409 During a hydrostatic test of a boiler, the safety valve or valves shall be removed or each valve disc shall be held to its seat by means of a testing clamp and not by screwing down the compression screw upon the spring. "Indicates changes by the Industrial Accident Commission of the State of California. J It is recommended that wherever possible the feed water entering boilers shall be not less than one hundred twenty (120) degrees Fahrenheit. APPENDIX EFFICIENCY OF JOINTS 410 Efficiency of Riveted Joints. The ratio which the strength of a unit length of a riveted joint has to the same unit length of the solid plate is known as the efficiency of the joint and shall be calculated by the general method illustrated in the following examples : TS = tensile strength stamped on plate, Ib. per sq. in. t = thickness of plate, in. ~b = thickness of butt strap, in. P = pitch of rivets, in., on row having greatest pitch J = diameter of rivet after driving, in. = diameter of rivet hole FIG. 21 EXAMPLE OF LAP JOINT, LONGITUDINAL OR CIRCUMFERENTIAL, SINGLE-EIVETED a = cross-sectional area of rivet after driving, sq. in. s = shearing strength of rivet in single shear, Ib. per sq/in., as given in Par. 16 S = shearing strength of rivet in double shear, Ib. per sq. in., as given in Par. 16 c = crushing strength of mild steel, Ib. per sq. in., as given in Par. 15 n = number of rivets in single shear in a unit length of joint N = number of rivets in double shear in a unit length of joint. REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. 411 Example: Lap joint, longitudinal or circumferential, single- riveted. A = strength of solid plate = PXtXTS B = strength of plate be ween rivet holes = (P d)t X TS C = shearing strength of one rivet in single shear =nXsXa D = crushing strength of plate in front of one rivet =dXtXc Divide B, C or D (whichever is the least) by A, and the quotient will be the efficiency of a single-riveted lap joint as shown in Fig. 21. TS = 55,000 Ib. per sq. in. t = Kin. =0.25 in. P = l^ in. = 1.625 in. d = ii in. =0.6875 in. a =0.3712 sq. in. s = 44,000 Ib. per sq. in. c= 95,000 Ib. per sq. in. A =1.625X0.25X55,000=22,343 B = (1.6250.6875) 0.25 X 55,000 = 12.890 C = 1 X 44,000 X0.3712 = 16,332 D = 0.6875 X0.25 X95,000 = 16,328 \

4> , . j>^ , FIG. 22 EXAMPLE OF LAP JOINT, LONGITUDINAL OR CIRCUMFERENTIAL, DOUBLE-RIVETED 12,890 (B) 22,343 (A) =0.576= efficiency of joint 412 Example: Lap joint, longitudinal or circumferential, double- riveted. A = strength of solid plate = PxtXTS B = strength of plate between rivet holes = (P d) t X TS C = shearing strength of two rivets in single shear = n Xs Xa D = crushing strength of plate in front of two rivets =nXdXtXc Divide B, C or D (whichever is the least) by A, and the quotient will be the efficiency of a double-riveted lap joint, as shown in Fig. 22. TS = 55,000 Ib. per sq. in. t = -fs in. =0.3125 in. P=2%in.=2.875in. d=% in. =0.75 in. 0=0.4418 sq. in. s = 44,000 Ib. per sq. in. 36,523 (B) 49,414 (A) c =95,000 Ib. per sq. in. ;! =2.875X0.3125X55,000 = 49,414 B = (2.875 0.75) 0.3125X55,000=36,523 0=2X44,000X0.4418=38,878 D =2X0.75X0.3 125X95,000 =44,531 =0.79 = efficiency of joint APPENDIX 97 413 Example: Butt and double strap joint, double-riveted. A = strength of solid plate =PXtXTS B = strength of plate between rivet holes in the outer row = (P d) t X TS C = shearing strength of two rivets in double shear, plus the shearing strength of one rivet in single shear =NXSXa -\-nXsXa D= strength of plate between rivet holes in the second row, plus the shearing strength of one rivet in single shear in the outer row = (P 2d) t X TS FIG. 23 EXAMPLE OF BUTT AND DOUBLE STRAP JOINT, DOUBLE-RIVETED E = strength of plate between rivet holes in the second row, plus the crushing strength .of butt strap in front of one rivet in the outer row = (P 2d) t XTS+dXbXc F = crushing strength of plate in front of two rivets, plus the crushing strength of butt strap in front of one rivet =NXdXtXc+nXdXbXc G = crushing strength of plate in front of two rivets, plus the shearing strength of one rivet in single shear = N XdXtXc+nXsXa H = strength of butt straps between rivet holes in the inner row = (P 2d) 2b X TS, This method of failure is not possible for thicknesses of butt straps required by these Rules and the computation need only be made for old boilers in which thin butt straps have been used. For this reason this method of failure will not be considered in other joints. Divide B, C, D, E, F, GOT H (whichever is the least) by A, and the quotient will 98 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. be the efficiency of a butt and double strap joint, double-riveted, as shown in Fig. 23. TS = 55,000 Ib. per sq. in. a =0.6013 sq. in. t = % in. =0.375 in. s =44,000 Ib. per sq. in. b= & in. =0.3 125 in. S = 88,000 Ib. per sq. in. P=4^g in. =4.875 in. c = 95,000 Ib. per sq. in. d= Kin. =0.875 in. Number of rivets in single shear in a unit length of joint = 1. Number of rivets in double shear in a unit length of joint =2. FIG. 24 EXAMPLE OF BUTT AND DOUBLE STRAP JOINT, TRIPLE-EIVETED A =4.875 X 0.375 X 55,000 = 100,547 B = (4.8750.875) 0.375 X 55,000 = 82,500 C =2X88,000X0.6013 + 1X44,000X0.6013 = 132,286 D = (4.875 2X0.875)0.375X55,000 + 1X44,000X0.6013=90,910 E = (4.875 2X0.875) 0.375X55,000+0.875X0.3125X95,000 =90,429 F =2 X0.875 X0.375 X 95,000 +0.875 X0.3125 X95,000 = 88,320 (7=2X0.875X0.375X95,000+1X44,000X0.6013=88,800 82,500 (B) 100,547 (A) = 0-S20 = efficie n cy of joint 414 Example: Butt and double strap joint, triple-riveted. A = strength of solid plate = PXtXTS B = strength of plate between rivet holes in the outer row = (P d) t X TS C shearing strength of four rivets in double shear, plus the s.hearing strength of one rivet in single shear =NXSXa+nXsXa D = strength of plate between rivet holes in the second row, plus the shearing strength of one rivet in single shear in the outer row = (P 2d) tXTS i-nXsXa APPENDIX 99 #=x A& a. O f plate between rivet holes in the second row, plus the crushing strength of buti, .+^,. n i n f ront o f one r i vet i n the outer row = (P2d) t XTS+dXbXc F = crushing strength of plate in front of four rivets, plua the crushing strength of butt strap in front of one rivet = NXdXtXc+nXdXbXc G = crushing strength of plate in front of four rivets, plus the shearing strength of one rivet in single shear = NXdXtXc+nXsXa Divide B, C, Z), E, F or G (whichever is the least) by A, and the quotient will be the efficiency of a butt and double strap joint, triple-riveted, as shown in Fig. 24. 7*5 = 55,000 Ib. per sq. in. a =0.5185 sq. in. t = H in. =0.375 in. s =44,000 Ib. per sq. in. 6= A in. =0.3125 in. =88,000 Ib. per sq. in. P = 6^ in. =6.5 in. c =95,000 Ib. per sq. in. d= H in. =0.8125 in. Number of rivets in single shear in a unit length of joint = 1. Number of rivets in double shear in a unit length of joint =4. A =6.5X0.375X55,000 = 134,062 B = (6.50.8125) 0.375X55,000 = 117,304 C =4X88,000X0.5185 + 1X44,000X0.5185 =205,326 D = (6.52 X0.8125) 0.375 X 55,000+1 X 44,000 X0.5185 = 123,360 E = (6.52 X0.8125) 0.375 X55,000+0.8125 X0.3125 X95,000 = 124,667 F=4X0.8125X0.375X95,000 + 1X0.8125X0.3125X95,000 = 139,902 G =4 X0.8125 X 0.375 X 95,000+1 X 44, 000X0.5185 = 138,595 i5S5 =o - 875=effidencyofioint 415 Example: Butt and double strap joint, quadruple-riveted. A = strength of solid plate =PXtXTS B = strength of plate between rivet holes in the outer row = (P d) t X TS C = shearing strength of eight rivets in double shear, plus the shearing strength of three rivets in single shear=2VXXa+nXsXa D = strength of plate between rivet holes in the second row, plus the shearing strength of one rivet in single shear in the outer row = (P 2d) tXTS +!XsXa E = strength of plate between rivet holes in the third row, plus the shearing strength of two rivets in the second row in single shear and one rivet in single shear in the outer row = (P Id) t X TS+n Xs Xa F=-- strength of plate between rivet holes in the second row, plus the crushing strength of butt strap in front of one rivet in the outer row = (P 2d) t XTS+dXbXc 100 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.B. row and one G= strength of plate between rivet holes in the third row, pl strength of butt strap in front of two rivets in + K ~ oon rivet in the outer row = (P 4d} t ^ T - s r n x d X & X c H = crushing strength of plat* iu front of eight rivets, plus the crushing strength of butt strap In front of three rivets =NXdXtXc+nXdXbXc I = crushing strength of plate in front of eight rivets, plus the shearing strength of two rivets in the second row and one rivet in the outer row, in single shear =NXdXtXc+nXsXa Divide B, C, D, E, F, G, H or / (whichever is the least) by A, and the quotient will be the efficiency of a butt and double strap joint quadruple-riveted, as shown in Fig. 25. FIG. 25 EXAMPLE OF BUTT AND DOUBLE STRAP JOINT, QUADRUPLE-KIVETED a = 0.6903 sq. in. s= 44,000 Ib. per sq. in. S= 88,000 Ib. per sq. in. c = 95,000 Ib. per sq. in. TS = 55,000 Ib. per sq. in. t= Kin. =0.5 in. b= s in. =0.4375 in. P = 15in. d= if in. =0.9375 in. Number of rivets in single shear in a unit length of joint =3. Number of rivets in double shear in a unit length of joint =8. A = 15X0.5X55,000 = 412,500 = (150.9375) 0.5X55,000 = 386,718 C =8X88,000 X0.6903 +3 X 44,000X0. 6903 =577,090 D = (15 2X0.9375) 0.5X55,000+1X44,000X0.6903=391,310 E = (154 X0.9375) 0.5 X 55,000 +3 X44,000 X0.6903 =400,494 F = (152 X0.9375) 0.5 X 55,000 +0.9375 X 0.4375 X95,000 = 399,902 G = (15 4X0.9375) 0.5X55,000+3X0.9375X0.4375X95,000=426,269 H = 8 X0.9375 X0.5 X95,000 +3 X0.9375 X0.4375 X95,000 = 473, 145 7 = 8 X0.9375 X0.5 X95,000 +3 X44,000 X0.6903 = 447,369 386,718 (B} 412,500 (A) =0.937 = efficiency of joint APPENDIX '. 101 416 Example: Butt and double strap joint, quintuple-riveted. A = strength of solid plate = PXtXTS B = strength of plate between rivet holes in the outer row = (F 5) tXTS C = shearing strength of 16 rivets in double shear, plus the shearing strength of seven rivets in single shear =NXSXa+nXsXa D= strength of plate between rivet holes in the second row, plus the shearing strength of one rivet in single shear in the outer row = (P 2d) tXTS +lXsXa E = strength of plate between rivet holes in the third row, plus the shearing strength of two rivets in the second row in single shear and one rivet in single shear in the outer row = (P 4d) tXTS+3XsXa FIG. 26 EXAMPLE OF BUTT AND DOUBLE STRAP JOINT, QUINTUPLE-KIVETED F = strength of plate between rivet holes in the fourth row, plus the shearing strength of four rivets in the third row, two rivets in the second row and one rivet in the outer row in single shear = (P 8d) tXTS+nXsXa G strength of plate between rivet holes in the second row, plus the crushing strength of butt strap in front of one rivet in the outer row = (P 2d) t XTS+dXbXc H = strength of plate between rivet holes in the third row, plus the crushing strength of butt strap in front of two rivets in the second row and one rivet in the outer row = (P 4d) tXTS+ZXdXbXc 7 = strength of plate between rivet holes in the fourth row, plus the crushing strength of butt strap in front of four rivets in the third row, two rivets in the second row and one rivet in the outer row = (P Sd) tXTS+n XdXbXc 102 TtEFORT O^ 1 BOILER CODE COMMITTEE, AM.SOC.M.E. J = crushing strength of plate in front of 16 rivets, plus the crushing strength of butt strap in front of seven rivets =NXdXtXc+nXdXbXc K = crushing strength of plate in front of 16 rivets, plus the shearing strength of four rivets in the third row, two rivets in the second row and one rivet in the outer row in single sheai=NXdXtXc+nXsXa Divide B, C, D, E, F, G, H, 7, J or K (whichever is the least) by A, and the quo- tient will be the efficiency of a butt and double strap joint, quintuple-riveted, as shown in Fig. 26 or Fig. 27. TS = 55,000 Ib. per sq. in. a = 1.3529 sq. in. t= % in. =0.75 in. s = 44,000 Ib. per sq. in. 1= Y 2 :in. =0.5 in. S = 88,000 Ib. per sq. in. P=36n. c = 95,000 Ib. per sq. in. in. = 1.3125 in. P= 36' 1 -H FIG. 27 EXAMPLE OF BUTT AND DOUBLE STRAP JOINT, QUINTUPLE-RIVETED Number of rivets in single shear in a unit length of joint =7. Number of rivets in double shear in a unit length of joint = 16. A =36 X0.75 X55,000 = 1,485,000 B = (361.3125) 0.75 X55,000 = 1,430,860 C = 16 X88,000 X 1.3529 +7 X44,000 X 1.3529 =2,321,578 D = (362 X 1.3125) 0.75 X55,000+l X 44,000 X 1.3529 = 1,436,246 E = (364 X 1 .3 125) 0.75 X 55,000 +3 X44,000 X 1 .3529 = 1,447,020 F = (36 8X1.3125)0.75X55,000+7X44,000X1.3529 = 1,468,568 G = (36 2X1.3125)0.75X55,000+1.3125X0.5X95,000 = 1,439,064 H = (364 X 1.3125) 0.75 X55,000+3 X 1.3125 X0.5 X95,000 = 1,455,472 / = (36 8X1.3125)0.75X55,000+7X1.3125X0.5X95,000 = 1,488,141 / = 16 X 1 .3125 X0.75 X95,000 +7 X 1.3125 X0.5 X95,000 = 1,932,266 # = 16X1.3125X0.75X95,000+7X44,000X1.3529 = 1,912,943 1,430,860 (B) 1,485,000 (A) = 0.963 = efficiency of joint APPENDIX 103 417 Figs. .28 and 29 illustrate other joints that may be used. The butt and double strap joint with straps of equal width shown in Fig. 28 may be so designed that it will have an efficiency of from 82 to 84 per cent and the saw-tooth joint shown in Fig. 29 so that it will have an efficiency of from 92 to 94 per cent. FIG. 28 ILLUSTRATION OF BUTT AND DOUBLE STRAP JOINT WITH STRAPS OF EQUAL WIDTH FIG. 29 ILLUSTRATION OF BUTT AND DOUBLE STRAP JOINT OF THE SAW-TOOTH TYPE 104 EEPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. BRACED AND STAYED SURFACES 4.18 The allowable loads based on the net cross-sectional areas of staybolts with V-threads, are computed from the following formulae. The use of Whitworth threads with other pitches is permissible. The formula for the diameter of a staybolt at the bottom of a V-thread is: D (P X 1.732) = d where D = diameter of staybolt over the threads, in. P pitch of threads, in. d diameter of staybolt at bottom of threads, in. 1.73i2 = a constant When IT. ,S. threads are used, the formula becomes D (P X 1.^3,2 X 0.75) = d Tables 11 and 12 give the allowable loads on net cross-sectional areas for staybolts with V-threads, having 12 and 10 threads per inch. TABLE 11. ALLOWABKE LOADS ON STAYBOLTS WITH V-THREADS, 12 THREADS PER INCH Outside Diameter of Diameter at Bottom of Net Cross- Sectional Area Allowable Load at 7500 Lb. Staybolts, In. Thread, In. (at Bottom of Thread) , Sq. In. Stress, per Sq. In. |/ 0.7500 0.6057 0.288 2160 ii 0.8125 0.6682 0.351 2632 % 0.8750 0.7307 0.419 3142 il 0.9375 0.7932 0.494 3705 .0000 0.8557 0.575 4312 A .0625 0.9182 0.662 4965 M .1250 0.9807 0.755 5662 _i. .1875 1.0432 0.855 6412 K .2500 1 . 1057 0.960 7200 ~fs .3125 1 . 1682 1.072 8040 % .3750 1.2307 1.190 8925 & .4375 1.2932 1.313 9849 iy* .5000 1 . 3557 1.444 10830 APPENDIX 105 TABLE 12. ALLOWABLE LOADS ON STAYBOLTS WITH V-THREADS, 10 THREADS PER INCH Outside Diameter of Diameter at Bottom Net Cross- Sectional Area Allowable Load at 7500 Lb. Staybolts, In. of Thread, In. (at Bottom of Thread), Sq. In. Stress per Sq. In. 1M 1.2500 1.0768 0.911 6832 1.3125 1 . 1393 1.019 7642 \% 1 . 3750 1.2018 1.134 8505 ITS 1 . 4375 1.2643 1.255 9412 1 V% 1.5000 1 . 3268 1.382 10365 1 ~V 1 . 5625 1.3893 1.515 11362 15/8 1 . 6250 1.4518 1.655 12412 419 Table 13 shows the allowable loads on net cross-sectional areas of round stays or braces. TABLE 13. ALLOWABLE LOADS ON ROUND BRACES OR STAY RODS Allowable Stress, in Lb. per Sq. In., Net Cross-sectional XT* Area Minimum Diameter of Circular JNet Cross-sectional Area of Stay, 6000 8500 9500 Qfoxr In otay, in. Allowable Load, in Lb., on Net Cross-sectional Area 1 1.0000 0.7854 4712 6676 7462 1^ 1.0625 0.8866 5320 7536 8423 l$i 1.1250 0.9940 5964 8449 9443 1 & 1 . 1875 1 . 1075 6645 9414 10521 \Yl 1.2500 1.2272 7363 10431 11658 1& 1.3125 1.3530 8118 115C1 12854 1% 1.3750 1.4849 8909 12622 14107 l'A 1.4375 1.6230 9738 13796 15419 1 '/$ 1 . 5000 1.7671 10603 15020 16787 1'A 1.5625 1.9175 11505 16298 18216 154 1.6250 2.0739 12443 17628 19702 1 H 1 6875 2.2365 13419 19010 21247 1M 1.7500 2.4053 14432 20445 22852 IB 1.8125 2.5802 15481 21932 24512 \Y % 1.8750 2.7612 16567 23470 26231 1ft 1.9375 2.9483 17690 25061 28009 2 2.0000 3.1416 18850 26704 29845 2^i 2.1250 3.5466 21280 30147 33693 2\i 2.2500 3.9761 23857 33797 37773 2 3 / 8 2.3750 4.4301 26580 37656 42086 2 J4 2.5000 4.9087 29452 41724 46632 2% 2.6250 5.4119 32471 46001 51413 2% 2.7500 5.9396 35638 50487 56426 2j| 2.8750 6.4918 38951 55181 61673 3 3.0000 7.0686 42412 60083 67152 420 Table 14 gives the net areas of segments of heads for use in computing stays. 106 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. TABLE 14. NET AREAS OF SEGMENTS OF HEADS Height from Tubes to Shell, In. Diameter of Boiler, In. 24 30 36 42 48 54 60 66 72 78 84 90 96 Area to be stayed, Sq. In. 8 8>"2 9 9^ 10 10H 11 HH 12 12}* 13 13}* 14 14}* 15 B* K ^ it* 8* 20J4 21 21V* 22' 22^ 23 8* ! 4 5 K ii H |?H 8* 15* s* 2* 31}* 32 W* %" 34}*.. 28 35 42 50 57 66 74 83 91 33 41 49 58 68 78 88 99 109 120 132 143 155 167 178 37 46 56 66 77 89 100 112 125 138 151 164 178 192 206 220 235 249 264 40 51 62 70 85 98 111 124 139 153 108 183 199 215 231 247 263 281 297 314 331 349 306 384 401 43 55 67 80 93 107 121 137 151 167 183 200 217 235 252 271 289 308 326 345 365 384 404 424 444 404 4S5 505 526 47 59 72 86 99 114 130 146 163 180 197 216 234 254 273 291 312 332 353 374 396 417 439 461 483 505 528 551 574 597 620 642 667 689 714 737 761 51 63 76 91 106 123 138 156 174 193 211 230 250 271 291 312 334 357 378 400 424 448 470 496 519 543 568 594 618 643 668 695 719 745 771 798 824 850 877 904 930 53 66 82 96 112 131 147 165 184 204 224 246 266 287 309 332 355 380 402 426 450 476 500 528 552 578 604 632 658 687 713 740 708 797 825 855 882 909 939 968 997 1028 1056 1084 1115 55 70 86 101 117 135 155 173 194 216 235 258 280 303 326 350 374 399 425 449 476 501 529 558 583 613 640 669 697 726 754 784 814 843 875 907 936 968 998 1030 1060 1092 1123 1155 1187 1218 1252 1286 1317 58 74 90 105 123 142 161 181 203 224 247 270 294 318 343 368 394 420 447 471 500 526 555 584 613 643 673 703 734 765 796 827 859 892 922 956 987 1024 1053 1089 1120 1157 1187 1221 1255 1290 1324 1359 1394 1430 1465 1500 1536 60 76 92 111 129 147 169 189 213 234 256 282 305 333 357 382 411 436 467 494 520 552 580 613 642 675 705 739 769 800 830 866 897 934 966 1003 1035 1073 1106 1145 1177 1211 1248 1284 1321 1358 1394 1433 1467 1508 1542 1578 1617 1654 1692 63 80 95 116 132 153 174 196 219 243 267 293 319 345 372 400 423 457 486 516 543 577 604 641 667 706 733 766 800 835 869 904 939 975 1010 1047 1083 1120 1157 1195 1232 1270 1305 1347 1382 1424 1459 1496 1538 1575 1617 1655 1695 1735 1775 1810 1857 65 82 98 119 137 160 183 204 230 252 279 302 331 360 386 417 443 475 502 536 564 598 631 663 699 729 766 797 835 867 906 945 978 1018 1051 1092 1126 1167 1202 1243 1279 1321 1360 1400 1442 1480 1523 1561 1605 1650 1687 1733 1770 1816 1856 1900 1941 1984 2026 35 35K. 36 36}* 37 APPENDIX 107 SAFETY YALVES 421 Method of Computing Table 8. The discharge capacity of a safety valve is expressed in equations 2 and 3 as the product of C and H. The discharge capacities are given in Table 8 for each valve size at the pressures shown and are calculated for various valve sizes, pressures and for three different lifts. The discharge capacities are proportional to the lifts, so that intermediate values may be obtained. from the Table by interpolation. C = total weight or volume of fuel of any kind burned per hour at time of maximum forcing, Ib. or cu. ft. H = the heat of combustion, B.t.u. per Ib. or cu. ft. of fuel used. D = diameter of valve seat, in. L = vertical lift of valve disc, in., measured immediately after the sudden lift due to the pop. P = absolute boiler pressure or gage pressure plus 14.7 Ib. per sq. in. 1100 = the number of B.t.u. required to change a pound of feed water at 100 deg. fahr. into a pound of steam. The boiler efficiency is assumed as 75 per cent. The coefficient of discharge, in Xapier's formula, is taken as 96 per cent. 6 for valve with 1100X3600 ~ 70 45-deg. seat. ( 1 ) for valve wita bevel seat at 45 deg. (2) for valve with flat seat at 90 deg. (3) METHOD OF CHECKING THE SAFETY VALVE CAPACITY BY MEASURING THE MAXIMUM AMOUNT OF FUEL THAT CAN BE BURNED 422 The maximum weight of fuel that can be burned is deter- mined by a test. The weight of steam generated per hour is found from the formula: 108 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. W = weight of steam generated per hour, Ib. C = total weight of fuel burned per hour at time of maxi- mum forcing, Ib. H = the heat of combustion of the fuel, B.t.u. per Ib. (see Par. 427). The sum of the safety valve capacities marked on the valves as provided for in the Eules shall be equal to or greater than the maxi- mum evaporative capacity of the boiler. Table 8 may be used for determining the number of safety valves required as illustrated in the following examples : 423 Example 1: A boiler at the time of maximum forcing uses 2150 Ib. of Illinois coal per hour of 12,100 B.t.u. per Ib. Boiler pres- sure, 2,25 Ib. per sq. in. gage. 2150X12,100 = CH = 26,015,000 Table 8 shows that two 3%-in. bevel seated valves with 0.11 in. lift, or one 3-in. bevel seated valve with 0.10 in. lift and one S^-in. bevel seated valve with 0.11 in. lift, would discharge the steam gen- erated. 424 Example 2: "Wood shavings of heat of combustion of 6400 B.t.u. per Ib. are burned under a boiler at the maximum rate of 2000 Ib. per hour. Boiler pressure, 100 Ib. per sq. in. gage. 2000X6400 = Cn = 12,800,000 Table 8 shows that two 3%-in. bevel seated valves with 0.11 in. lift, or one 3-in. bevel seated valve with 0.08 in. lift and one 4-in. bevel seated valve with 0.12 in. lift, would discharge the steam generated. 425 Example 3: An oil-fired boiler at maximum forcing uses 1000 Ib. of crude oil (Texas) per hour. Boiler pressure. 275 Ib. per sq. in. gage. 1000X18,500 .= CTI = 18,500,000 Table 8 shows that two 3%-in. bevel seated valves with 0.06 in. lift, or two 3-in. flat seated valves with 0.05 in. lift, or two ,2%-in. flat seated valves with 0.06 in. lift, would discharge the steam gen- erated. 42>6 Example 4- A boiler fired with natural gas consumes 3000 cu. ft. per hour. The working pressure is 150 Ib. per sq. in. gage. 3000X960 = CH-= 2,880,000 APPENDIX 109 Table 8 shows that two IJ-in. bevel seated valves with 0.05 in. lift, or two 1-in. flat seated valves with 0.04 in. lift, would discharge the steam generated. *427 For the purpose of checking the safety valve capacity as described in Par. 422, the following UNIT values of heats of com- bustion of various fuels in B.t.u. may be used : B.t.u. per lb. Semi-bituminous coal - 14,500 Anthracite 13,700 Screenings 12,500 Coke 13,500 Wood, hard or soft, kiln dried 7,700 Wood, hard or soft, air dried 6,200 Shavings 6,400 Peat, air dried, 25 per cent moisture 7,500 Lignite 10,000 Kerosene : 20,000 Petroleum, crude oil, Penn _ 20,700 Petroleum, crude oil, Texas 18,500 Petroleum, crude oil, California 18,500 B.t.u. per cu. ft. Natural gas 960 Blast furnace gas 100 Producer gas 150 Water gas, uncarburetted 290 "Indicates changes by the Industrial Accident Commission of the State of California. REPORT OF BOILER CODE COMMITTEE, AM.SUu.~r 00 CO 00 CO <* r-t CO 00 t-^ i-HiOl> CO CO O CO O b- OTt< O5 ^ CO (N O 00 (N 00 * CD CO iO C CO 1C r-i t- iO i-( -rH COOOO500 iO a5fOCOl>-Tt-*>O.-llOCOr-< I S i-H 1C t^ CO CO O CM -t^i-HO- o 3 ^SSS^S^^co^wSsa -. iC(NOiOO CDCO^i-H CO r-t CO t^ O (M (N CO CO 00 t-H (N (N 10 CO --H 00 -H IN CO-* Tt<(N ^HO^HrHCO * C^ CO >-i 1O ^rHi-l CO r-H (N T-I Tfi TjH (N CO CM CM 1-1 CM 1-1 -^ CO I-H IN CM (N ^ fl 3 a bolting for large sizes. h a nut at each end is imum design of head to f esent time. Box wrench to be used on ded. 1 ^ in. diameter and larger stud wi conveniently pulled up with wrenches of mi led up with socket wrenches. ed face to be ft in. gures given are for center to no 3 t extenYbe^ond the 24 in. size at the pres bolts with hexagonal nuts are recommende nuts for pipe sizes 1 in. to 16 in. can be in. to 48 in. can be conveniently pull tween inside edges of bolt holes and rai e spot bored for nuts. > f flanges given in table includes raise be of Fi sdon head nal n sizes 18 ance bet ges to NOTES: Late?aFs Square h Hexa Dist Flan Thic 112 REPORT OF BOILER CODE COMMITTEE, AM.SOC.M.E. t-C LU O id Qi tD z o d UJ b h- o Ul UJ X o CQ UJ OD O O UJ A i I K-Y-> t f iler builder's stamps, location of 80 333 builder's stamps, not to be covered 80 334 bushing, for feed pipe connection 77 315 plate steel, specifications for 11 23- 39 to be stamped A.S.M.E. std 79 332 wet bottom, distance from floor line 79 326 wet bottom, distance from floor line (heating boilers) 86 369 Braced and stayed surfaces 49 199-233 Braced and stayed surfaces 104 418 117 118 INDEX TO COMPLETE RULE'S PAGE PAR. Braces, diameter of pins, area of rivets in and design of crowfeet for. ... 55 223 made of Kteel plate 7 5 made of steel plate (guasets) 56 224 spacing between 51 203 steel bars for 7 6 when welded 7 4 Brackets, to support h.r.t. boilers 79 325 Brown furnaces 63 243-244 B.t.u. of various fuels 109 427 Butt and double-strap joint double riveted 97 413 triple riveted 98 414 quadruple riveted 99 415 quintuple riveted . 101 416 Butt straps, tables of minimum thicknesses of 9 19 straps, to be rolled or formed 45 191 Straps, of equal width 103 417 straps, saw tooth 103 417 Calking 65 257 Capacity of safety valves examples of checking 108 423-426 method of checking 107 422-427 method of checking (existing installations) 91 391392 Cast iron (See gray iron castings or malleable castings) for headers 64 246 used with superheated steam 8 12 boiler, hydrostatic pressure test of 87 372 boiler, maximum pressure allowed on 87 374 boiler, section to be tested 87 372 headers, maximum pressure allowed on, existing installations 90 382 headers, maximum pressure allowed on, power boilers 64 245-247 headers, tested to destruction 64 247 Cast steel (See steel) Castings, specifications for gray iron 26 95110 specifications for malleable iron 29 1111-0 specifications for steel , . 22 77- 94 Channel irons for flat heads 50 201 Check valve on feed-pipe 77 317 Check valve on feed-pipe, existing installations 93 406 Chocking safety valve capacity, method of 107 422-427 Checking safety valve capacity, method of, existing installations 91-92 391-392 Circular furnaces and flues 61 239-241 Circular manhole opening 65 258 Circumferential joints 44 184-185 Cleanout door in setting 79 327 Cock (See valves, gage cocks, blow-off cocks) Combined area of safety valves 74 280 Combustion chamber, materials to be used in 7 2 Combustion chamber, sling stays 60 235-236 Combustion chamber, tube sheets of 59 234 Cones, truncated, maximum allowable working pressure on 58 231 Connections, flanged 82 346 safety valve 73 277-278 steam gages 75 296 water column 78 320-321 Contraction of steam mains, provision for 76 305 Convex and concave heads 49 195 Corrugated furnaces 63 243 Covers, manhole and handhole . 7 5 INDEX TO COMPLETE RULES 119 PAGE PAB. Covers, manhole, material 67 262 Cross boxes, material of 8 9 Cross pipes connecting steam and water drums, material of 8 9 Crown bars and girder stays 58 230 Crushing strength of steel plate 8 15 Crushing strength of steel plate, existing installations 90 387 Crushing strength, applied to joints 95 410 Curved surfaces to be stayed 58 230 D Damper regulator, connected to steam space 86 365 Damper regulator, connected to water column 75 295 Damper regulator, connected to water column, existing installations 92 397 Diagonal braces 54 221 stays, stresses in 54 221-222 tube holes in shell or drum 47 193 Dial of steam gage 75 297 Diameter of fusible metal in fusible plug 113 429 Diameter of rivet holes, old boilers 91 388 Direct spring-loaded, safety valve, construction of 69 272 Discharge capacity of safety valves 68 270-274 Discharge pipe from safety valves 73 278279 Dished heads 49 195-198 Dished heads, corner radius of 49 197 Dished heads, with manhole opening 49 195 Pomes 48 194 Door, access and firing, minimum size of. 79 327-328 Door, access and firing, minimum size of, heating boilers 86 370 Door, frame rings, material of 8 13 Door latches 79 328 Doubling plates 50 199 Down-draft boilers, safety valves for 85 359 Drains from stop valves 76 303-304 from stop valves, existing installations . 93 400 from superheater 76 306 Drilling rivet holes 65 253-254 Drilling tube holes 64 248-249 Drum or shell, longitudinal joints of (See joints) 45 187 Drum, material of 7 E Edge of plate to center of rivet 44 183 Edges of plates for calking 65 257 Edges of tube holes to be removed 64 249 Efficiency of ligament, between tube holes 46 192 of ligament, between diagonal tube holes 47 193 of riveted joints 44 181 of riveted joints, to calculate 95-103 410-417 Elbow on escape pipe, from safety valve 73 Elliptical manhole, size of 65 End of feed pipe, to be open 77 314 Ends of stay-bolts, to be riveted over 50 200 of stays below tubes 53 216 of tubes, fire-tube boilers 64 250 of tubes, water-tube boilers, and superheaters . 64 251-252 Equalizer, to support h.r.t. boilers 78 Escape pipe, from safety valve Escape pipe, from safety valve, existing installations 92 Escape pipe, from safety valve, heating boilers 83 Examples of checking safety valve capacities 108 423-426 Existing installations 89 ~ 94 378-409 120 INDEX TO COMPLETE KULES PACK PAB. Existing installations, steam heating boilers 90 383 Expansion of steam mains, provisions for 76 305 Extra heavy fittings on blow-off 77 310811 Extra thick tube, for fusible plug 113 429 F Factors of safety for domes when single riveted 48 194 existing boilers 89 379 new installations 43 180 second hand boilers 90 381 steel heating boilers , 81 340 Feed pipe, ends to be open 77 314 Feed pipe, fittings and valves on 77 C17 Feed piping, power boilers 77 314-318 piping, existing installations 94 406 water discharge 77 315 water, discharge clear of joints 77 316 water regulator, connection to 75 295 water supply apparatus 78 C18 Fire-box steel, for shells, drums 7 2 box steel, specifications for 11 23- 39 brick casing, for blow-off pipe 77 312 tube boiler, manhole in 67 264 tube boiler, thicknesses of tubes cf 10 22 Firing doors 79 327-328 Fittings and appliances, existing installations 92 D95-407 Fittings and appliances, heating boilers 66 364-368 Fittings and appliances, power boilers 76 299-322 Flange fittings, tables of sizes of 110-111 of manhole opening 54 218 Bteel, for heating boilers 81 337 steel, for shells, drums 7 3 Bteel specifications for 11 23- 39 Flanged connections, heating boilers 82 346 Flanged construction for water leg and door frame rings 8 13 Flanges, cast iron, thickness of 76 299 Flanges, reinforcing, thickness and material of 68 268 Flaring of tube ends 64 251 Flat surfaces, to be stayed 49 199 Flat surfaces, to be stayed between tubes and between tubes and shell. ... 53 216 Flues, circular, pressure allowed on 61 241 Fox furnaces 63 243-244 Fuels, heats of combustion of 3 09 427 Furnace sheets, stamps to be visible on 79 331 Furnaces : Adamson type 62 242 Brown 63 243 circular flues 61 241 corrugated 63 243 Fox 63 243 internal cylindrical, staying of 52 212 Leeds suspension bulb 63 243 material of 7 2 Morison 63 243 plain circular 61 239-240 Purves 63 243 thickness of corrugated or ribbed 64 244 vertical boilers 60 237-238 Fusible plugs 113 428-430 Fusible plugs, location of 113 430 INDEX TO COMPLETE RULES 121 G PAGE PAB. Gage, altitude 85 362 cocks, existing installations 93 396 cocks, heating boilers 86 367 cocks, power boilers 75 294 inspector's, connection for 75 298 steam and connections, existing installations 93 398 steam and connections, heating boilers 85 361 steam end connections, power boilers 75 296 steam, dial of 75 297 water, glass, existing installations 92-93 395-396 water, glass, heating boilers 86 366 water, glass, power boilers 75 291-295 Gas fired boilers, safety valves for 85 360 Girder stays and crown bars 58 230 Globe valve, not to be used on blow-off , 77 308 Globe valve on feed pipe 77 314 Grate surface, table of, for safety valves 84 358 Gray iron castings, specifications for 26 95-110 Gusset stays, stresses in 54 221-224 H Handhole covers, material ......' 7 5 Handholes, in h.r.t. boilers 67 264 in locomotive type boiler 67 265 in vertical fire engine boilers 67 267 in vertical fire tube boilers 67 266 Headers, cast iron, existing installations 90 382 cast iron, new boilers 64 245 cast iron, pressure allowed on 64 245-247 and pressure parts, material of 8 9 Heads, angles for staying upper segments 56 225-229 area of segments to be stayed 53 213-214 217 area of segments to be stayed, table for 106 420 convex end concave 49 195-198 segments of, area to be stayed 53 213-214 217 Stamps to be visible 79 331 stiffeners for 50 201 Heating boilers 81 Heating boilers, existing installations 90 383-384 Heating boilers, to which the rules of power boilers shall apply 81 335 Heat of combustion of various fuels 109 427 Holes for rivets ' 65 254 for screw stays 52 210 for wash-out, heating boilers for wash-out, power boilers 67 265-267 Horizontal return tubular boilers: location of feed-water discharge 77 315 longitudinal joints, to be above fire line 45 189 manhole below tubes 67 264 maximum length of joint 45 190 method of supporting 78 323-324 staying heads of, 36 in or less 56 225 water column connections 78 320 Hot water boilers 8i 335-377 Hydrostatic pressure test of cast iron headers 64 247 heating boilers 87 372-374 old boilers 94 408-409 power boilers 79 329-330 on sections of cast iron boiler 87 372 122 INDEX TO COMPLETE RULES I PAGE PAR. Inspection at shop, heating boilers 87 375 Inspector's test gage connection 75 298 Inspirator or injector, used to feed boiler 78 318 Insulating material, not to cover boiler stamps 80 334 Internal pipe, in steam space 75 290 Iron, cast (See cast iron) for stay bolts, specifications for 34 139-150 rivets, specifications for 31 121-138 rivets, shearing strength of 8 16 wrought, stays and stay bolts 7 7 -wrought, stays and stay bolts, specifications 34 139-150 wrought, tensile strength, existing installations 90 385 wrought, water leg and door frame rings 8 13 J Joints, back pitch 44 182 Joints, butt and double strap, double riveted, example of 97 413 butt and double strap, triple riveted, example of 98 414 butt and double strap, quadruple riveted, example of 99 415 butt and double strap, quintuple riveted, example of 101 416 butt and double strap, required on shell or drum over 36 in. diameter 45 187 calking of 65 257 circumferential 44 184-185 of domes 48 198 efficiency of 44 181 efficiency of, detailed methods of calculation 95 410 existing boilers 89 380 heating boilers 82 341-344 lap, double riveted, longitudinal or circumferential, example of 96 412 lap crack 90 384 lap riveted, allowed on shell or drum not over 36 in. diameter 45 188 lap riveted, allowed on domes 48 194 lap single riveted, longitudinal or circumferential, example of 96 411 longitudinal 45 187-191 longitudinal lap joints on heating boilers 82 341 longitudinal, location of rivet holes on 44 183 longitudinal of furnace v.t. boiler to be staybolted 60 238 longitudinal of h.r.t. boiler to be above the fire line 45 189 longitudinal of h.r.t. boiler to be above the fire line, heating boilers. . 86 371 longitudinal, maximum length of 45 190 longitudinal, maximum length of, heating boilers 82 342 power boilers 44 181-191 protection of 82 344 welded 45 186 L Lamphrey fronts, valves on 78 319 Lamphrey fronts, valves on, existing installations 94 407 Lap joint crack 90 384 Lap joints: length of, heating boilers 82 342 length of, power boilers 45 190 longitudinal or circumferential, single riveted 96 411 longitudinal or circumferential, double riveted 96 412 longitudinal domes 48 194 longitudinal hot water boilers 82 343 longitudinal lap crack 90 384 longitudinal, steam heating boilers 82 341 Lap welded tubes, specifications for 40 164-178 Latches, door 79 328 INDEX TO COMPLETE RULES 123 PAGE PAK. Laying out shell plates, furnace sheets and heads 79 331 Leeds suspension bulb furnaces 63 243 Length of stays between supports 54 220 Ligament between tube holes, efficiency of 46 192-193 Load allowed on stay-bolts 54 220 Location of A.S.M.E. stamp 80 333 of domes 48 194 of fusible plugs 113 430 Locomotive type boiler, water leg and door frame rings 8 13 Longitudinal joints 45 187191 steam heating boilers ' . . . . 82 341 hot water boilers 82 343 lap crack 90 384 on domes 48 194 of h.r.t. boilers to be above fire line, heating boilers 86 371 of h.r.t. boilers to be above fire line, power boilers 45 189 Low pressure steam boiler 81 335-377 Lugs, made of steel plate 7 5 Lugs, to support h.r.t. boilers 78 323325 M Main steam pipe, stop valve on 76 301-304 Malleable castings, specifications for 29 111-120 Manholes 65 258-264 below tubes, h.r.t. boiler 67 264 below tubes, h.r.t. boiler, staying of 54 218 covers, material of 67 262 covers, when plate steel 7 5 in a dished head 49 198 frame, riveting of 65 260 frame, proportions of 66 261 gaskets, bearing surface of 67 263 in any fire tube boiler, over 40 in. diameter 67 264 in dome heads 67 264 openings, minimum sizes of 65 258 plates, material of < 67 262 reinforcement, material of 65 259 reinforcement, on boiler 48 in. diameter or over 65 260 Manufacture (See specifications) Manufacturer's name, heating boilers 87 377 Manufacturer's stamp 79 332 Manufacturer's stamp not to be covered 80 334 Materials, selection of 7 1-13 Materials, selection of, for heating boilers 81 335-337 Maximum allowable working pressure braced and stayed surfaces 49 199 existing boilers 89 378-384 heating boilers 81 338-340 shells of power boilers 43 179-180 Methods of support 78 323-325 Morison furnaces 63 243-244 Mud drums, maximum allowable working pressure 90 382 Mud drums, material of 8 10 Muffler on safety valves 73 279 N Name, manufacturers, on heating boilers 87 377 Non-return stop valves, automatic 76 303 Nozzles, material of 8 12 Nozzles, and fittings 76 299 Number of gage cocks 75 294 Numbers, serial 79 332 124 INDEX TO COMPLETE RULES PAGE PAR. OG flanged construction 8 13 Oil-fired boilers, safety valves for 85 360 Openings, flanged connections, heating boilers 82 346 Openings, threaded to be reinforced 68 268 Outside screw and yoke valves, on steam pipe 76 301 Outside screw and yoke valves, on water column 75 293 P Pins in braces, diameter of 55 223 Pipes, bottom blow-off and fittings, existing installations 93-94 401-405 bottom blow-off and fittings, heating boilers 86 364 bottom blow-off and fittings, power boilers 77 308 feed and fittings 77 314-317 in steam space 75 290 main steam, valves on 76 301 or nipple, number of threads into fitting 76 300 or nipple, number of threads into fitting, table 68 268 surface blow-off and fittings 76 307 threads, minimum number of 68 268 water column, and fittings 78 320 Piping, feed 77 314-318 Pitch of rivets 44 182 of rivets 95 410 of stay-bolts 50 199 of stay-bolts, table 51 203 of stay tubes 59 233 Planing edges of plates 65 257 Plate, steel, specifications for 11 23- 39 Plates, thickness, in shell or dome after flanging 9 18 minimum thickness of in a boiler 9 17- 20 minimum thickness of stayed flat surface 49 199 Plugs, fusible 113 428-430 Power boilers 7-80 1-334 Power boiler requirements for certain heating boilers 81 335 Pressure, allowed on cast iron boilers 81 338 allowed on shell or drum, formula for existing installations ^ 89 378 allowed on shell or drum, formula for, power boilers 43 180 maximum allowable working, on flat surfaces, power boilers. 49 199 maximum allowable working, old boilers 89 378-384 maximum allowable working, old boilers steam heating 90 383 maximum allowable working, heating boilers 81 338-340 maximum allowable working, on shells, power boilers 43 179-180 parts over 2 in., material of 8 9 parts of superheaters, material of 8 11 Protection of joints 82 344 Pump, to supply feed water 78 318 Purves furnaces 63 243 R Regulators, damper 86 365 Reinforced threaded openings in shell, heads of drums 68 268 Relief valves for hot water boilers 83 349-350 Reservoirs, on steam mains 76 305 Rings, waterleg and door frame, material of 8 13 Rivet holes, finish and removal of burrs 65 253-254 iron, specifications for 31 121-138 steel, specifications for 15 40- 62 Riveted joints (See joints) Riveting 65 253-256 INDEX TO COMPLETE RULES 125 Rivets PACE PAE. allowable shearing strength of 8 16 allowable shearing strength of, existing installations 90 386 existing boilers, diameter of 90 388 in braces, area of 55 223 in shear on lugs or brackets 79 325 in shear on manhole frames 65 260 length of and heads for 65 255 machine driven. 65 256 material of 8 8 to completely fill rivet holes 65 255 Rolling, ends of shell plates 45 191 O Safety, factor of for existing boilers 89 379 for existing lap joint boilers 89 380 for power boilers 43 180 for steel heating boilers 81 340 Safety valves additional on existing installations 92 393 blow-down adjustment 74 281 capacity, method of checking 107 422-427 connections, existing boilers 92 394 connections, heating boilers 83 347 connections, power boilers 73-74 276278 280 289-290 construction 74 282-287 construction, heating boilers 84 356-358 discharge capacity, existing boilers 91-92 391-392 discharge capacity, power boilers 68 270-274 discharge capacity, table of 70-72 escape pipe for 73 278 escape pipe for, existing installations 92 394 escape pipe for, heating boilers 83 355 for down draft boilers 85 359 for existing installations 91 389-394 for heating boilers 83 347-360 for oil and gas fired boilers 85 360 formula for 107 421 formula for heating boilers 8^-84 351358 method of computing and checking 107 421-427 method of computing and checking, existing installations 91-92 391-392 muffler on 73 279 muffler on. existing installations 92 394 power boilers 68 269290 required on boiler 68 269 required on boiler, existing installations 91 390 required on heating boilers 83 348 seats of 69 272 seats of heating boilers 84 357 setting of 68 271-281 setting of, existing installations 91 390 setting of, existing installations, heating boilers 83 348 size limits, heating boilers 83 351 size limits, power boilers 69 272 stamping of 69 273 stamping of, heating boilers 84 357 superheater 74 288-289 taft-e of, for heating boilers 84 356 test of 73 275 testing of existing installations 91-92 391 126 INDEX TO COMPLETE RULES PAGE PAB. Saw-tooth type of butt and double strap joint 103 417 Screwed stays, supporting of 54. 219 Seamless tubes, specifications for 40 164-178 Seats of safety valves 69 272 Second hand boilers 90 331 Sections of cast iron, to be tested 87 372 Segment, area to be stayed 53 214-217 of head, to be stayed 53 213 method of determining net areas, water tube boilers 53 215 Segments, table of ' 106 420 Selection of material 7 1-13 Serial number 79 333 Setting of safety valves 68 271 of safety valves, existing installations 91 390 of safety valves, existing installations, heating boilers 83 348 Setting, method of, wet bottom heating boilers 86 369 Setting, method of, wet bottom power boilers 79 326 Settings, heating boilers 86 369-371 Settings, power boilers 78 323-328 Shearing strength of rivets 8 16 Shearing strength of rivets, existing installations 90 386 Shell or drum, longitudinal joints of 45 187-190 or drum, to determine alowable pressure on, new boilers 43 180 or drum, to determine allowable pressure on, existing boilers 89 378 plate, thickness of 9 17 20 Shut-off valves on water column pipes 75 293 Shop inspection of heating boilers 87 375 Sizes of flanged fittings, tables 110-111 Sling stays 60 235-236 Specifications for gray iron castings 26 95-110 lap welded and seamless boiler tubes 40 164-178 material, heating boilers 81 336 malleable castings 29 111-120 plate steel 11 23- 39 refined wrought iron bars 37 151-153 rivet iron 31 121-138 rivet steel 15 40- 62 stay bolt iron 34 139-150 stay bolt steel 19 63 steel bars 19 64- 76 steel castings 22 77- 94 Stamping boilers A.S.M.E. std 79 332 Stamps, A.S.M.E. std., location of 80 333 Stamps, not to be covered by insulation 80 334 Stamps, to be visible on shell plates, furnaces sheets and heads 79 331 Stay bolted surface, to compute allowable pressure on 49 199 Stay bolts adjacent to edges of stay-bolted surface 51 205 adjacent to furnace door or other opening 52 206 adjacent to furnace joint, v.t. boiler 60 238 diameter of, how measured 52 208 ends of 50 200202 211 holes for 52 210 iron, specifications for 34 139-150 material of '. 7 7 maximum allowable stress on 54 220 pitch of 49 199-204 steel, specifications for 19 63 tables of allowable load on 104 418-419 Staved and braced surfaces 49 199-233 Stayed flat surface 49 199 INDEX TO COMPLETE RULES 127 PAGE PAR. Staying heads 55 222 heads h.r.t. boiler 36 in. or less diameter 56 225-229 dished heads 49 196 furnaces 52 212 segments of heads 53 213 segments of heads with manhole opening 54 218 Stay-rods, ends riveted over, to be supported 54 219 Stay-tubes 58 232-233 Stays, crown bars and girders 58 230 cross sectional area in calculating 52 209 diagonal and gusset, stresses in 54 221222 224 maximum allowable stress 54 220 Sling 60 235-236 tables of allowable load on 104 418-419 screwed, supporting of 54 219 upset for threading 52 211 and stay-bolts, allowable stress on 54 220 and stay-bolts, table of allowable stress on 104 418419 Steam gage and connections, existing installations 93 398 398a gage and connections, heating boilers 85 361 gage and connections, power boilers. 75 296298 heating boilers, existing installations 90 383-384 mains 76 305 mains, reservoirs on. 76 305 outlets "..... 76 301 outlets, existing installations 93 399 Steel bars, for boiler parts 7 6 castings, specifications for 22 77- 94 crushing strength of plate 8 15 for rivets, specifications for 15 40 62 for stay-bolts, specifications for 19 63 plates exposed to fire 7 2 plates when firebox quality not specified 7 3 plates, shearing strength of 8 16 stays and stay-bolts 49 199-212 tensile strength of, existing installations 90 385 wrought or cast, for boiler and superheater parts 8 11 plate, crushing strength of 8 15 plate, heating boilers 81 335-340 plate, specifications for 11 23- 39 plate, tensile strength of 8 14 Stop valves (See valves) Straps, butt, of equal width 103 417 Straps, butt, saw-tooth 103 417 Superheater drains 76 306 safety valve on 74 288-289 tubes and nipples 64 251-252 Superheaters and mountings, material for ; 8 11- 12 Support, methods of, for boilers 78 323-326 Support of stays, ends riveted over 54 219 Surface blow-off 76 307 Suspended type of setting h.r.t. boilers 78 324 T Table of angles for staying heads 56 225 constants for pitch of stay tubes 59 233 discharge capacities of spring-loaded safety valves 6970 71-72 flange fittings, standard 110 flange fittings, extra heavy Ill 128 INDEX TO COMPLETE RULES PAGE PAR. Table of maximum allowable pitch of stay-bolts, ends riveted 51 204 maximum allowable stresses for stays and stay-bolts 54 220 minimum pipe threads for boiler connections 68 268 net areas of segments 106 420 round braces or stay rods allowable loads 105 419 sizes of safety valves, heating boilers 84 358 sizes of rivets, existing boilers 90 388 stay-bolts, allowable loads, 12 threads per inch 104 418 stay-bolts, allowable loads, 10 threads per inch 105 413 thickness of butt straps 9 19 Tensile strength of steel or wrought iron, existing installations 90 385 Tensile strength of steel plate 8 14 Test, hydrostatic, of existing installations 94 408-409 hydrostatic, of heating boilers 87 372-375 hydrostatic, of power boilers 79 329-330 of safety valve, existing installations 9192 391 of safety valve, power boilers 73 275 of steam gage 75 298 gage, connection for 75 298 Thermometers on hot water boilers 86 363 Thickness of corrugated or ribbed furnace 64 244 required for boiler plates 9 17 required for butt straps 9 19 required for dome plates after flanging 9 18 required for shell plates 9 18 required for tube sheets 9 20 required for tubes 10 21- 22 Threaded openings 68 268 Threads, pipe or nipple into fitting 76 300 Threads, table 68 268 Tin, for fusible plugs 113 428 Truncated cones, maximum allowable working pressure on 58 231 Tube ends, fire tube boiler 64 250 ends, warfer tube boilers and superheaters 64 252 for fusible plug 113 429 heads, upper, staying segments of by steel angles 56 225-229 heads, of water tube boilers 53 215 holes and ends 64 248-252 holes, diagonal, in shell \>r drum 47 193 holes in shell or drum 46 192 holes, sharp edges to be removed 64 249 sheets of combustion chambers 59 234 sheets, minimum thickness of 9 20 sheets, space allowed unstayed between tubes and between tubes and shell 53 216 Tubes for fire-tube boilers, thicknesses of 10 22 for water-tube boilers, thicknesses of 10 21 lapwelded and seamless, specifications for 40 164-178 required thickness 10 21- 22 stay 58 232-233 V Valves, automatic, on water glass 75 292 automatic non-return stop 76 303 extra heavy, on bottom blow-off 77 311 extra heavy, on main steam pipe 76 302 globe, not to be used on blow-off 77 308 globe, on feed pipe 77 314 on bottom blow-off 77 308-311 on bottom blow-off, existing installations 93 401-403 on every steam outlet 76 301 on feed pipe 77 317 on feed pipe, existing installations 94 406-4066 INDEX TO COMPLETE RULES 129 PAGB PAR. Valves, on Lamphrey fronts 78 319 on Lamphrey fronts, existing installations 94 407 outside screw and yoke type, on steam pipes 76 301 outside screw and yoke type, on water column 75 293 safety [See safety valves) stop 76 301-304 stop, drains for 76 303-304 stop, existing installations 93 399 stop, existing installations, drains 93 400 Vertical boilers, furnaces of 60 237-238 fire-tube boiler, manhole in 67 264 fire-tube boiler, waterleg and door frame ring 8 13 W Washout holes, hot water boilers 82 345 Washout holes, power boilers 67 265-267 Water column and connections, existing installations. . . 93 397 column end connections, heating boilers '. . . . . 86 368 column and connections, power boilers 75 295 column and connections, power boilers 78 320-322 glass and gage cocks, location of, power boilers 75 291-292 glass, automatic valves not allowed 75 292 glasses, existing installations 92 395 glasses, heating boilers 86 366 relief valves for hot water boilers 83 349-350 Waterleg rings, material of 8 13 Water tube boilers cast iron for headers of 64 246 flaring of tube ends 64 251 thicknesses of tubes of 10 21 wrought or cast steel parts of 8 9 Welded joints 45 186 Welded stays 52 209 Wet bottom boilers, height from floor line 79 326 Wet bottom boilers, height from floor line, heating boilers 86 369 Working pressure, maximum allowable existing installations 89 378-384 power boilers 43 179-180 steam and hot water boilers 81 338-340 Wrought iron (See iron) Wrought steel (See steel). INDEX TO RULES FOR NEW INSTALLA- TIONS OF POWER BOILERS PAGE PAB. Access and firing doors, power boilers. 79 327-328 Adamson furnace 62 242 Adjustment of safety valves for blow down 74 281 Allowable load on stay-bolts, table of 104 418-419 loads on circular braces 105 419 loads on stays, table of 105 419 stress on stays 52 209 stress on stays and stay-bolts 54 220 working pressure, power boilers 43 179-180 Angles on h.r.t. boiler heads, 36 in. or less diameter 56 225-229 Area of segment, formula for 54 217 segments of heads to be stayed 53 214 segments, table of 106 to be stayed in heads 53 214-217 to be stayed in heads having manhole 54 218 Automatic shut-off valves 75 292 non-return stop valves 76 303 B Back pitch of riveted joints 44 182 Bars, steel for boiler parts 7 6 steel, specifications for 19 64- 76 refined iron, specifications for 37 151-163 Beading of tube ends 64 250 Blow down for safety valves 74 281 Blow-off cock 77 309-311 piping new installations 76 307-313 pipe and fittings 77 311 Boiler, builder's stamps, location of 80 333 builder's stamps, not to be covered 80 334 bushing, for feed pipe connection 77 315 plate steel, specifications for 11 23- 39 to be stamped A. S. M. E. std 79 332 wet bottom, distance from floor line ' 79 326 Braced and stayed surfaces 49 199-233 Braced and stayed surfaces 104 418 Braces, diameter of pins, area of rivets in and d"esign of crowfeet for. ... 55 223 made of steel plate 7 5 made of steel plate, gussets 56 224 spacing between 51 203 steel bars for 7 6 when welded 7 4 Brackets, to support h.r.t. boilers 79 325 Brown furnaces 63 243244 B.t.u. of various fuels 109 427 Butt and double-strap joint, double riveted 97 413 and double-strap joint, triple riveted 98 414 and double-strap joint, quadruple riveted 99 415 131 132 INDEX, NEW INSTALLATIONS OF POWER BOILERS PAGB PAR. Butt and double-strap joint, quintuple riveted 101 416 straps, tables of minimum thicknesses of 9 19 straps, to be rolled or formed 45 191 straps of equal width 103 417 straps, saw tooth 103 417 Calking 65 257 Capacity of safety valves, examples of checking 108 423-426 Capacity of safety valves, method of checking 107 422-427 Cast iron (See gray iron castings or malleable castings) for headers 64 246 used with superheated steam 8 12 headers, maximum pressure allowed on, power boilers 64 245-247 headers, tested to destruction 64 247 Cast steel (See steel) Castings, specifications for gray iron 4 26 95-110 specifications for malleable iron 29 111-120 specifications for steel 22 77- 94 Channel irons for flat heads 50 201 Check valve on feed-pipe 77 317 Checking safety valve capacity, method of 107 422-427 Circular furnaces and flues 61 239-241 Circular manhole opening 65 258 Circumferential joints 44 184-185 Cleanout door in setting 79 327 Cock (See valves, gage cocks, blowoff cocks) Combined area of safety valves 74 280 Combustion chamber, material to be used in 7 2 Combustion chamber, sling stays 60 235-236 Combustion chamber, tube sheets of 59 234 Cones, truncated, maximum allowable working pressure on 58 231 Connections, safety valve 73 277278 steam gages 75 296 water column 78 320-321 Contraction of steam mains, provisions for 76 305 Convex and concave heads 49 195 Corrugated furnaces 63 243 Covers, manhole and handhole 7 5 Covers, manhole, material 67 262 Cross boxes, material of 8 9 Cross pipes connecting steam and water drums, material of 8 9 Crown bars and girder stays 58 230 Crushing strength of steel plate 8 15 Crushing strength applied to joints 95 410 Curved surfaces to be stayed 58 230 D Damper regulator, connected to water column 75 295 Diagonal braces 54 221 stays, stresses in 54 221-222 tube holes in shell or drum 47 193 Dial of steam gage 75 297 Diameter of fusible metal in fusible plug 113 429 Direct spring-loaded safety valve, construction of 69 272 Discharge capacity of safety valves 68 270-274 Discharge pipe from safety valves 73 278-279 Dished heads 49 195-198 Dished heads, corner radius of 49 197 Dished heads with manhole opening 49 195 Domes . 48 194 INDEX, NEW INSTALLATIONS OF POWER BOILERS 133 PAGE PAR. Door, access and firing, minimum size of 79 327328 Door, frame rings, material of 8 13 Door latches 79 328 Doubling plates 50 199 Drains from stop valves 76 303304 Drains from superheater 76 306 Drilling rivet holes 65 253-254 Drilling tube holes 64 248-249 Drum or shell, longitudinal joints of (See joints) 45 187 Drum, material of 7 2- 3 E Edge of plate to center of rivet, distance from 44 183 Edges of plates for calking 65 257 Edges of tube holes to be removed 64 249 Efficiency of ligament, between tube holes 46 192 of ligament, between diagonal tube holes 47 193 of riveted joints 44 181 of riveted joints, to calculate 95-103 410-417 Elbow on escape pipe, from safety valve 73 279 Elliptical manhole, size of 65 258 End of feed pipe, to be open 77 314 Ends of stay-bolts, to be riveted over 50 200 stays below tubes 53 216 tubes, fire-tube boilers 64 250 tubes, water-tube boilers, and superheaters 64 251-252 Equalizer, to support h.r.t. boilers 78 324 Escape pipe, from safety valve 73 278-279 Examples of checking safety valve capacities 108 423-426 Expansion of steam mains, provisions for 76 305 Extra heavy fittings on blow-off 77 310-311 Extra thick tube, for fusible plug 113 429 F Factors of safety for domes when single riveted 48 194 Factors of safety for new installations 43 180 Feed pipe, ends to be open 77 314 pipe, fittings and valves on 77 317 piping, power boilers 77 314-318 water, discharge 77 315 water, discharge clear of joints 77 316 water, regulator, connection to 75 295 water, supply apparatus 78 318 Fire-box steel, for shells, drums . 7 2 -box steel, specifications for 11 2339 brick casing, for blow-off pipe 77 312 tube boiler, manhole in 67 264 tube boiler, thicknesses of tubes of 10 22 Firing doors 79 327-328 Fittings and appliances, power boilers 76 299-322 Flange fittings, tables of sizes of 110-111 of manhole opening 54 218 steel for shells, drums 7 3 steel specifications for 11 23- 39 Flanged construction for water leg and door frame rinfn 8 13 Flanges, cast iron, thickness of 76 299 Flanges, reinforcing, thickness and material of 68 268 Flaring of tube ends 64 251 Flat surfaces, to be stayed 49 199 Flat surfaces, to be stayed between tubes and between tubes and shell. ... 53 216 Flues, circular, pressure allowed OTI 61 241 Fox furnaces , 63 243-244 134 INDEX, NEW INSTALLATIONS OF POWER BOILERS PAGE PAB. Fuels, heats of combustion of 109 427 Furnace sheets, stamps to be visible on . 79 331 Furnaces Adamson type 62 242 Brown 63 248 circular flues 61 241 corrugated 63 243 Fox 63 243 internal cylindrical, staying of 52 212 Leeds suspension bulb 63 243 material of 7 2 Morison 63 243 plain circular 61 239-240 Purves 63 243 thickness of corrugated or ribbed 64 244 vertical boilers 60 237-238 Fusible plugs 113 428-430 Fusible plugs, location of 113 430 / G Gage cocks, power boilers 75 294 inspector's, connection for 75 298 steam and connections, power boilers 75 296 steam dial of 75 297 water, glass 75 291-295 Girder stays and crown bars 58 230 Globe valve, not to be used on blow-off 77 308 Globe valve, on feed pipe 77 314 Gray iron castings, specifications for 26 95-110 Gusset stays, stresses in 54 221-224 H Handhole covers, material 7 5 Handholes, in h.r.t. boilers 67 264 in locomotive type boilers 67 2G5 in vertical fire engine boilers 67 267 in vertical fire tube boilers 67 266 Headers, cast iron, new boilers 64 245 cast iron, pressure allowed on 64 245-247 and pressure parts, material of 8 9 Heads, angles of staying upper segments 56 225-229 area of segments to be stayed 53 213-214 217 area of segments to be stayed, table for 106 420 convex and concave 49 195-198 segments of, area to be stayed 53 213-214 217 stamps to be visible 79 331 stiffeners for 50 201 Heat of combustion of various fuels 109 427 Holes tor rivets 65 254 screw stays 52 210 washout, power boilers 67 265-267 Horizontal return tubular boilers location of feed-water discharge 77 315 longitudinal joints, to be above fire line 45 189 manhole below tubes 67 264 maximum length of joint 45 190 method of supporting 78 323-324 staying heads of, 36 in. or less 56 225 water column connections 78 320 INDEX, NEW INSTALLATIONS OF POWER BOILERS 135 Hydrostatic pressure test PAGE PAR. of cast iron headers 64 247 power boilers 79 329-330 I Inspector's test gage connection 75 298 Inspirator or injector, used to feed boiler 78 318 Insulating material, not to cover boiler stamps 80 334 Internal pipe, in steam space 75 290 Iron, cast (See cast iron) for stay bolts, specifications for 34 139-150 rivets, specifications for 31 121-138 rivets, shearing strength of 8 16 wrought, stays and stay bolts 7 7 wrought, stays and stay bolts, specifications 34 139-150 wrought, waterleg and door frame rings 8 13 J Joints, back pitch 44 182 butt and double strap, double riveted, example of 97 413 butt and double strap, triple riveted, example of 98 414 butt and double strap, quadruple riveted, example of 99 415 butt and double strap, quintuple riveted, example of 101 416 Joints, butt and double strap, required on shell or drum over 36 in. diameter 45 187 calking of 65 257 circumferential 44 184-185 of domes 48 198 efficiency of 44 181 efficiency of detailed methods of calculation 95 410 lap, double riveted, longitudinal or circumferential, example of 96 412 lap riveted, allowed on shell or drum not over 36 in. diameter 45 188 lap riveted, allowed on domes 48 194 lap, single riveted, longitudinal or circumferential, example of 96 411 longitudinal 45 187-191 longitudinal, location of rivet holes on 44 183 longitudinal, of furnace, v.t. boiler to be stay-bolted 60 238 longitudinal, of h.r.t. boiler to be above the fire line 45 189 longitudinal, maximum length of 45 190 power boilers .' 44 181-191 welded 45 186 L Lamphrey fronts, valves on 78 319 Lap joints, length of, power boilers 45 190 joints, longitudinal or circumferential, double riveted 96 412 joints, longitudinal or circumferential, single riveted 96 411 joints, longitudinal domes 48 194 wolded tubes, specifications for 40 164-178 Latches, door 79 328 Laying out shell plates, furnace sheets and heads 79 331 Leeds suspension bulb furnaces 63 243 Length of stays between supports 54 220 Ligament between tube holes, efficiency of 46 192-193 Load allowed on stay-bolts 54 220 Location of A. S. M. E. stamp 1 . . . 80 333 domes 48 194 fusible plugs 113 430 Locomotive type boiler, water leg and door frame rings 8 13 Longitudinal joints 45 187-191 joints on domes 48 194 joints of h.r.t. boilers to be above the fire line 45 189 Lugs, made of steel plate 7 5 Lugs, to support h.r.t. boilers 78 323-325 136 INDEX, NEW INSTALLATIONS OF POWER BOILERS M PAGE PAR. Main steam pipe, stop valve on 76 301-304 Malleable castings, specifications for 29 111120 Manhole in dome heads 67 264 openings, minimum sizes of 65 258 plates, material of 67 262 reinforcement, material of 65 259 reinforcement, on boiler 48 in. diameter or over 65 260 Manholes 65 258-264 below tubes, h.r.t. boiler 67 264 below tubes, h.r.t. boiler, staying of 54 218 covers, material of 67 262 covers, when plate steel 7 5 in a dished head 49 198 frame, riveting of 65 260 frame, proportions of 66 261 gaskets, bearing surface of 67 263 in any fire tube boiler, over 40 in. diameter 67 264 Manufacture (See specifications) Manufacturer's stamp 79 332 Manufacturer's stamp, not to be covered 80 334 Materials, selection of 7 1-13 Maximum allowable working pressure braced and stayed surfaces 49 199 shells of power boilers 43 179-180 Methods of support 78 323-325 Morison furnaces 63 243244 Mud drums, material of 8 10 Muffler on safety valves 73 279 N Non-return stop valves, automatic 76 303 Nozzles, material of 8 12 Nozzles and fittings 76 299 Number of gage cocks 75 294 Numbers, serial 79 332 O OG flanged construction < 8 13 Openings, threaded to be reinforced 68 268 Outside screw and yoke valves, on steam pipe 76 301 Outside screw and yoke valves, on water column 75 293 P Pins in braces, diameter of 55 223 Pipes, bottom blow-off and fittings, power boilers 77 308 feed and fittings 77 314-317 in steam space 75 290 main steam, valves on 76 301 or nipple, number of threads into fitting 76 300 or nipple, number of threads into fitting, table 68 268 surface blow-off and fittings 76 307 threads, minimum number of 68 268 water column, and fittings 78 320 Piping, feed 77 314-318 Pitch of rivets 44 182 of rivets 95 410 stay-bolts 50 199 stay-bolts, table 51 203 stay tubes 59 233 INDEX, NEW INSTALLATIONS OF POWER BOILERS 137 PAGB PAB. Planing edges of plates 65 257 Plate, steel, specifications for 11 23- 39 Plates, thickness, in shell or dome after flanging 9 18 minimum thickness of in a boiler 9 17- 20 minimum thickness of stayed flat surface 49 199 Plugs, fusible 113 428-430 Pressure, allowed on shell or drum, formula for, power boilers 43 180 maximum allowable working, on flat surfaces, power boilers 49 199 maximum allowable working, on shells, power boilers 43 179-180 parts over 2 in., material of 8 9 parts of superheaters, material of 8 11 Pump, to supply feed water 78 318 Purves furnaces 63 243 R Reinforced threaded openings in shell, heads or drums 68 268 Reservoirs, on steam mains 76 305 Rings, waterleg and door frame, material of 8 13 Rivet holes, finish and removal of burrs 65 253-254 iron, specifications for 31 121-138 steel, specifications for 15 40- 62 Riveted joints (See joints) Riveting 65 253-256 Rivets allowable shearing strength of 8 16 in braces, area of 55 223 in shear on lugs or brackets 79 325 in shear on manhole frames 65 260 length of and heads for 65 255 machine driven 65 256 material of 8 8 to completely fill rivet holes 65 255 Rolling, ends of shell plates 45 191 S Safety, factor of, for power boilers 43 180 Safety valve blow-down adjustment 74 281 capacity, method of checking 107 422-427 connections, power boilers 7374 276-278 280 289-290 construction 74 282-287 discharge capacity, power boilers 68 270-274 discharge capacity, table of 70-72 escape pipe for 73 278 formula for 107 421 method of computing and checking 107 421427 muffler on 73 279 power boilers 68 269-290 required on boiler 68 269 seats of 69 272 setting of 68 271-281 size limits, power boilers 69 272 stamping of 69 273 superheater 74 288-289 test of 73 275 Saw-tooth type of butt and double strap joint 103 417 Screwed stays, supporting of 54 219 Seamless tubes, specifications for 40 164-178 Seats of safety valves 69 272 Sections of cast iron, to be tested 87 372 138 INDEX, NEW INSTALLATIONS OF POWER BOILERS PAGB PAE. Segment, area to be stayed 53 214217 of head, to be stayed 53 213 method of determining net areas, water tube boilers 53 215 Segments, table of 106 420 Selection of materials 7 113 Serial number 79 332 Setting of safety valves 68 271 Settings, power boilers 78 323-328 Setting of wet bottom power boilers 79 326 Shearing strength of rivets 8 16 Shell or drum, longitudinal joints of 45 187-190 Shell or drum, to determine allowable pressure on, new boilers 43 180 Shell plate, thickness of 9 17- 20 Shut-off valves on water column pipes 75 293 Sizes of flanged fittings, tables 110-111 Sling stays 60 235-236 Specifications for gray iron castings 26 95-110 lap welded and seamless boiler tubes 40 164-178 malleable castings 29 111-120 plate steel 11 23- 39 refined wrought iron bars 37 151-153 rivet iron 31 121-138 rivet steel 15 40- 62 stay bolt iron -. 34 139-150 stay bolt steel 19 63 steel bars 19 64- 76 steel castings 22 77- 94 Stamping boilers A.S.M.E. std 79 332 Stamps, A.S.M.E. std., location of 80 333 Stamps, not to be covered by insulation 80 334 Stamps, to be visible on shell plates, furnace sheets and heads 79 331 Stay bolted surface, to compute allowable pressure on 49 199 Stay bolts adjacent to edges of stay-bolted surface 51 205 adjacent to furnace door or other opening 52 206 adjacent to furnace joint, v.t. boiler 60 238 diameter of, how measured 52 208 ends of 50 200-202 211 holes for 52 210 iron, specifications for 34 139-150 material of 7 7 maximum allowable stress on 54 220 pitch of 49 199-204 steel, specifications for 19 63 tables of allowable load on 104 418-419 Stayed and braced surfaces 49 199-233 Stayed flat surface 49 199 Staying heads 55 222 heads h.r.t. boiler 36 in. or less diameter 56 225-229 dished heads 49 196 furnaces 52 212 segments of heads 53 213 segments of he-ids with manhole opening 54 218 Stay-rods, ends riveted over, to be supported 54 219 Stay-tubes 58 232-233 Stays, crown bars and girders 58 230 cross sectional area in calculating 52 209 diagonal and gusset, stresses in 54 221-222 224 maximum allowable stress 54 220 60 235-236 INDEX, NEW INSTALLATIONS OF POWER BOILERS PAGB PAK. Stays, tables of allowable load on 104 418-419 screwed, supporting of 54 219 upset for threading 52 211 and stay-bolts, allowable stress on 54 220 end stay-bolts, table of alloAvable stress on. 104 418-419 Steam gage and connections, power boilers 75 296-298 mains 76 305 mains, reservoirs on 76 305 outlets 76 301 Steel bars, for boiler parts 7 6 castings, specifications for 22 77 94 crushing strength of plate 8 15 for rivets, specifications for 15 40 62 for stay-bolts, specifications for 19 63 plates exposed to fire 7 2 plates whan firebox quality not specified 7 3 plates, shearing strength of 1 8 16 stays and stay-bolts 49 199-212 wrought or cast, for boiler and superheater parts 8 11 plate, crushing strength of 8 15 plate, specifications for 11 23 39 plate, tensile strength of 8 14 Stop valves (See valves) Straps, butt, of equal width 103 417 Straps, butt, saw-tooth 103 417 Superheater drains 76 306 safety valve on 74 288-289 tubes and nipples 64 251-252 Superheaters and mountings, material for S 11- 12 Support, methods of, for boilers 78 323-326 Support, of stays, ends riveted over 54 219 Surface blow-off 76 307 Suspended type of setting h.r.t. boilers 78 324 T Table of angles for staying heads 56 225 constants for pitch of stay tubes 59 233 discharge capacities of spring-loaded safety valves 69-72 flange fittings, standard 110 flange fittings, extra heavy Ill maximum allowable pitch of stay-bolts, ends riveted 51 204 maximum allowable stresses for stays and stay-bolts 54 220 minimum pipe threads for boiler connections 68 268 net areas of segments 106 420 round braces or stay rods, allowable loads 105 419 stay-bolts, allowable loads, 12 threads per inch 104 418 stay-bolts, allowable loads, 10 threads per inch 105 418 thickness of butt straps 9 19 Tensile strength of steel plate '. 8 14 Test, hydrostatic, of power boilers 79 329-330 of safety valve, power boilers 73 275 of steam gage 75 298 gage, connection for 75 298 Thickness of corrugated or ribbed furnace 64 244 required for boiler plates 9 17 required for butt straps 9 19 required for dome plates after flanging 9 required for shell plates 9 18 required for tube sheets 9 20 required for tubes 1 Threaded openings 68 268 140 INDEX, NEW INSTALLATIONS OF POWER BOILERS PAGE PAB. Threads, pipe or nipple into fitting 76 300 Threads, table 68 268 Tin, for fusible plugs 113 428 Truncated cones, maximum allowable working pressure on 58 231 Tube ends, fire tube boiler 64 250 ends, water tube boilers and superheaters 64 252 for fusible plug 113 429 heads, staying upper segments of, by steel angles 56 225-229 heads, of water tube boilers 53 215 holes and ends 64 248-252 holes, diagonal, in shell or drum 47 193 holes in shell or drum 46 192 holes, sharp edges to be removed 64 249 sheets of combustion chambers 59 234 sheets, minimum thickness of 9 20 sheets, space allowed unstayed between tubes and between tubes and shell 53 216 Tubes for fire-tube boilers, thicknesses of 10 22 . for water tube boilers, thicknesses of 10 21 lapwelded and seamless, specifications for 40 164-178 required thickness 10 21- 22 stay 58 232-233 Y Valves, automatic, on water glass 75 292 automatic non-return stop 76 303 extra heavy, on bottom blow-off 77 311 extra heavy, on main steam pipe 76 302 globe, not to be used on blow-off \ . . 77 308 globe, on feed pipe 77 314 on bottom blow-off 77 308-311 on every steam outlet .' 76 301 on feed pipe 77 317 on Lamphrey fronts 78 319 outside screw and yoke type, on steam pipes 76 301 outside screw and yoke type, on water column 75 293 safety (See safety valves) stop 76 301-304 stop, drains for 76 303-304 Vertical boilers, furnaces of 60 237-238 fire-tube boiler, manhole in 67 264 fire-tube boiler, waterleg and door frame ring 8 13 W Washout holes, power boilers 67 265-267 Water column and connections, power boilers 78 320-322 column and connections, power boilers 75 295 glass and gage cocks, location of, power boilers 75 291-292 glass, automatic valves not allowed 75 292 tube boilers, cast iron for headers of 64 246 tube boilers, flaring of tube ends 64 251 tube boilers, thicknesses of tubes of 10 21 tube boilers, wrought or cast steel, parts of 8 9 Waterleg rings, material of 8 13 Welded joints 45 186 Welded stays ^ 52 209 Wet bottom boilers, height from floor line 79 326 Working pressure, maximum allowable, power boilers 43 179-180 Wrought iron (See iron) Wrought steel (See steel) IXDEX TO RULES FOR NEW INSTALLA- TIONS OF HEATING BOILERS PAGB PAE. Access and firing doors, heating boilers 86 370 Allowable working pressure, heating boilers 81 338-340 Allowable working pressure, existing installations, steam heating boilers. . 90 383 Altitude gages 85 362 Area, grate surface, table to determine size of safety valves 84 356 B Blow-off cock, heating boilers 86 364 Blow-off piping, heating boilers 86 364 Boiler wet bottom, distance from floor line, heating boiler 86 369 Butt and double-strap joint double riveted 97 413 triple riveted 98 414 quadruple riveted 99 415 quintuple riveted 101 416 Cast iron boiler hydrostatic pressure test of 87 372 maximum pressure allowed on 87 374 section to be tested 87 372 Connections, flanged 82 346 Crushing strength applied to joints 95 410 D Damper regulator, connected to steam space 86 365 Diameter of fusible metal in fusible plug 113 429 Door, access and firing, minimum size of, heating boilers 86 370 Down-draft boilers, safety valves for 85 359 E Efficiency of riveted joints, to calculate 95-103 410-417 Escape pipe, from safety valve, heating boilers ' 83 355 Existing installations, steam heating boilers 90 383 Extra thick tube, for fusible plug 113 429 F Factors of safety for steel heating boilers 81 340 Fittings and appliances, heating boilers ; 86 364-368 Flange fittings, tables of sizes of 110-111 Flange steel, for heating boilers 81 337 Flanged connections, heating boilers 82 346 Fusible plugs 113 428-430 Fusible plugs, location of 113 430 141 142 INDEX, NEW INSTALLATIONS OF HEATING BOILERS PAGE PAR. Gage, altitude 85 362 cocks, heating boilers 86 367 steam and connections, heating boilers 85 361 water glass, heating boilers 86 366 Gas fired boilers, safety valves for x 85 360 Grate surface, table of, for safety valves 84 358 H Heating boilers 81 335-377 Heating boilers, to which the rules' of power boilers shall apply 81 335 Holes for wash-out, heating boilers 82 345 Hot water boilers ; 81 335-377 Hydrostatic pressure test heating boilers 87 372-374 on sections of cast iron boiler 87 372 I Inspection at shop, heating boilers . . 87 375 J Joints, butt and double strap, double riveted, example of 97 413 'butt and double strap, triple riveted, example of 98 414 butt and double strap, quadruple riveted, example of 99 415 butt and double strap, quintuple riveted, example of 101 416 efficiency of detailed methods of calculation 95 410 heating boilers ' 82 341-344 lap, double riveted, longitudinal or circumferential, example of 96 412 lap riveted, allowed on shell or drum not over 36 in. diameter 45 188 lap single riveted, longitudinal or circumferential, example of 96 411 longitudinal lap joints on heating boilers 82 341 longitudinal of h.r.t. boiler to be above the fire line, heating boilers. . 86 371 longitudinal, maximum length of, heating boilers 82 342 protection of 82 344 L Lap joints length of, heating boilers 82 342 longitudinal or circumferential, single riveted 96 411 longitudinal or circumferential, double riveted 96 412 longitudinal hot water boilers 82 343 longitudinal, steam heating boilers 82 341 Location of fusible plugs 113 430 Longitudinal joints, steam heating boilers 82 341 Longitudinal joints, hot water boilers 82 343 Longitudinal joints of h.r.t. boilers to be above the fire line 86 371 Low pressure steam boiler 81 335-377 M Manufacturer's name, heating boilers 87 377 Materials, selection of, for heating boilers 81 335-337 Maximum allowable working pressure, heating boilers ' 81 338-340 N Name, manufacturer's, on heating boilers 87 377 INDEX, NEW INSTALLATIONS OF HEATING BOILERS O 143 PAGE PAR. Oil-fired boilers, safety valves for 85 360 Openings, flanged connections, heating boilers 82 346 P Pipes, bottom blow-off and fittings, heating boilers 86 364 Pitch of rivets 95 410 Plugs, fusible 113 428-430 Power boiler requirements for certain heating boilers 81 335 Pressure, allowed on cast iron boilers 81 338 maximum allowable working, old boilers, steam heating 90 383 maximum allowable working, heating boilers 81 338-340 Protection of joints 82 344 R Regulators, damper 86 365 Relief valves for hot water boilers 83 349-350 Riveted joints (See joints) S Safety, factor of, for steel plate, heating boilers 81 340 Safety valve connections, heating boilers 83 347 Safety valve construction, heating boilers 84 356-358 escape pipe for heating boilers 83 355 for down draft boilers 85 359 for heating boilers 83 347-360 for oil and gas fired boilers 85 360 for formula for heating boilers 83-84 351-358 required on heating boilers 83 348 seats of, heating boilers 84 357 setting of, existing Installations, heating boilers 83 348 size limits, heating boilers 83 351 stamping of heating boilers 84 357 table of, for heating boilers 84 356 Saw-tooth type of butt and double strap joint 103 417 Setting of safety valves, existing installations, heating boilers 83 348 Settings, heating boilers 86 369-371 Setting of wet bottom heating boilers 86 369 Shop inspection of heating boilers 87 375 Sizes of flanged fittings, tables 110-111 Specifications for material, heating boilers 81 336 Steam gage and connections, heating boilers 85 361 Steam heating boilers, existing installations 90 383-384 Steel plate heating boilers , 81 335-340 Straps, butt, of equal width 103 417 Straps, butt, saw-tooth 103 417 T Table of flange fittings, standard 110 of flange fittings, extra heavy Ill of sizes of safety valves, heating boilers 84 358 of stay-bolts, allowable loads, 12 threads per inch 104 418 of stay-bolts, allowable loads, 10 threads per inch 105 418 Test, hydrostatic, of heating boilers 87 372-375 Thermometers on hot water boilers 86 363 Threads, table 68 268 144 INDEX, NEW INSTALLATIONS OF HEATING BOILERS PAGH PAR. Tin, for fusible plugs 113 428 Tube for fusible plug 113 429 Valves, safety (See safety valves) W Washout holes, hot water boilers. 82 345 Water column and connections, heating boilers 86 368 glasses, heating boilers 86 366 relief valves for hot water boilers 83 349-350 Wet bottom boilers, height from floor line, heating boilers 86 369 Working pressure, maximum allowable, steam and hot water boilers 81 338-340 INDEX TO RULES FOR EXISTING INSTALLATIONS. A PAGE PAR. Additional safety valves, existing installations 92 393 Age limit for lap seam boilers 89 380 Allowable working pressure, existing installations 89 378-384 B Blow-off cock, existing installations 93 401-403 Blow-off piping, existing installations 93-94 401-105 B.t.u. of various fuels . '. 109 427 Butt and double-strap joint double riveted 97 413 triple riveted 98 414 quadruple riveted 99 415 quintuple riveted 101 416 C Capacity of safety valves, examples of checking 108 423-426 Capacity of safety valves, method of checking, existing installations 91-92 391-392 Cast iron headers, maximum pressure allowed on, existing installations 90 382 Check valve on feed-pipe, existing installations 94 406 Checking safety valve capacity, method of, existing installations 91-92 391-392 Cock (See valves, gage cocks, blow-off cocks) Crushing strength of steel plate, existing installations 90 387 Crushing strength, applied to joints 95 410 D Damper regulator connected to water column, existing installations 93 397 Diameter of fusible metal in fusible plug 113 429 Diameter of rivet holes, old boilers 91 388 Drains from stop valves, existing installations 93 400 E Efficiency of riveted joints, to calculate 95-103 410-417 Escape pipe, from safety valve, existing installations 92 394 Extra thick tube, for fusible plug - 113 429 F Factors of safety for existing boilers 89 379 Factors of safety for second-hand boilers 90 381 Feed piping, existing installations 94 406-406b Fittings and appliances, existing installations 92-93 395-407 Fuels, heats of combustion of 109 427 Fusible plugs 113 428-430 Fusible plugs, location of G Gage cocks, existing installations 92 396-396a Gage, steam and connections, existing installations 93 398-398a Gage, water glass, existing installations 92 395-396 145 146 INDEX TO RULES FOR EXISTING INSTALLATIONS. H PAGE PAR. Headers, cast iron, existing installations 90 382 Heating boilers, existing installations __. 90 383-384 Heat of combustion of various fuels 109 427 Hydrostatic pressure test, old boilers 94 408-409 I Iron wrought, tensile strength, existing installations 90 385 J Joint, butt and double strap, double riveted, example of 97 413 butt and double strap, triple riveted, example of 98 414 butt and double strap, quadruple riveted, example of 99 415 butt and double strap, quintuple riveted, example of 101 416 efficiency of, detailed methods of calculation 95 410 existing boilers 89 380 lap, double riveted, longitudinal or circumferential, example of 96 412 lap crack _. 90 384 lap riveted, allowed on shell or drum not over 36 in. diameter 45 188 lap single riveted, longitudinal or circumferential, example of 96 411 L Lamphrey fronts, valves on existing installations 94 407 Lap joint crack 90 384 joints, longitudinal or circumferential, single riveted 96 411 joints, longitudinal or circumferential, double riveted 96 412 joints, longitudinal lap crack 90 384 Location of fusible plugs 113 430 Longitudinal joints, lap crack.. 90 384 M Maximum allowable working pressure, existing boilers 89 378-384 Mud drums, maximum allowable working pressure 90 382 P Pipes, bottom blow-off and fittings, existing installations 93-91 401-405 Pitch of rivets 95 410 Plugs, fusible 113 428-. ( 30 Pressure, allowed on shell or drum, formula for existing installations 89 378 Pressure, maximum allowable working, old boilers 89 378-384 R Riveted joints (See joints) Rivets, allowable shearing strength of, existing installations 90 383 Rivets, existing boilers, diameter of 91 388 S Safety valve, test of existing installations 91-92 391 Saw-tooth type of butt and double strap joint 103 417 Second hand boilers 90 381 Setting of safety valves, existing installations 91 390 Shearing strength of rivets, existing installations 90 386 Shell or drum, to determine allowable pressure on, existing boilers 89 378 Steam gage and connections, existing installations 93 398 Steam outlets, existing installations 93 399 Steel, tensile strength of, existing installations 90 383 Stop valves (See valves) INDEX TO KULES FOR EXISTING INSTALLATIONS. 147 T PAGE PAR. Table of sizes of rivets, existing boilers 91 388 Tensile strength of steel or wrought iron, existing installations 90 385 Test, hydrostatic, existing installations 94 408-409 Test, of safety valve, existing installations 91-92 391 Tin, for fusible plugs 113 428 Tube for fusible plug 113 429 V Valves, on bottom blow-off, existing installations 93 401-403 on feed pipe, existing installations 94 406 on Lamphrey fronts, existing installations 94 407 safety (See safety valves) stop, existing installations 93 399 stop, existing installations, drains 93 400 W Water column and connections, existing installations 93 397 Water glasses, existing installations 92 395 Working pressure, maximum allowable, existing installations _ 89 378-384 _ OF 25 OVERDUE- ' TB UNIVERSITY OF CALIFORNIA LIBRARY \