1、Designation: A266/A266M 18Standard Specification forCarbon Steel Forgings for Pressure Vessel Components1This standard is issued under the fixed designation A266/A266M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of la
2、st revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This specification2covers four gr
3、ades of carbon steelforgings for boilers, pressure vessels, and associated equip-ment.NOTE 1Designations have been changed as follows:Current FormerlyGrade 1 Class 1Grade 2 Class 2Grade 3 Class 3Grade 4 Class 41.2 Supplementary requirements are provided for use whenadditional testing or inspection i
4、s desired. These shall applyonly when specified individually by the purchaser in the order.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independ
5、ently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.4 Unless the order specifies the applicable “M” specifica-tion designation, the material shall be furnished to the inch-pound units.1.5 This international standard was developed in accor-dance w
6、ith internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standar
7、ds:3A275/A275M Practice for Magnetic Particle Examination ofSteel ForgingsA370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA788/A788M Specification for Steel Forgings, General Re-quirementsA1058 Test Methods for Mechanical Testing of SteelProductsMetricE112 Test Methods for D
8、etermining Average Grain SizeE165/E165M Practice for Liquid Penetrant Examination forGeneral IndustryE381 Method of Macroetch Testing Steel Bars, Billets,Blooms, and Forgings2.2 Other Standard:ASME Boiler and Pressure Vessel Code, Section IX43. Ordering Information and General Requirements3.1 In add
9、ition to the ordering information required bySpecification A788/A788M, the purchaser shall include withthe inquiry and order a detailed drawing, sketch, or writtendescription of the forging.3.2 Material supplied to this specification shall conform tothe requirements of Specification A788/A788M, whic
10、h out-lines additional ordering information, manufacturingrequirements, testing and retesting methods and procedures,marking, certification, product analysis variations, and addi-tional supplementary requirements.3.3 If the requirements of this specification are in conflictwith the requirements of S
11、pecification A788/A788M, therequirements of this specification shall prevail.3.4 For hubbed flat heads and tube sheets ordered forASMEBoiler and Pressure Vessel Code application, SupplementaryRequirement S12 of Specification A788/A788M shall bespecified in addition to Supplementary Requirement S8 of
12、 thisspecification.4. Materials and Manufacture4.1 The steel shall be made in accordance with the MeltingProcess Section of Specification A788/A788M. A sufficient1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsi
13、bility of SubcommitteeA01.06 on Steel Forgings and Billets.Current edition approved March 1, 2018. Published March 2018. Originallyapproved in 1943. Last previous edition approved in 2013 as A266/A266M 13.DOI: 10.1520/A0266_A0266M-18.2For ASME Boiler and Pressure Vessel Code applications, see relate
14、d Specifi-cation SA266/SA266M in Section II of that code.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Ava
15、ilable from American Society of Mechanical Engineers (ASME), ASMEInternational Headquarters, Two Park Ave., New York, NY 10016-5990, http:/www.asme.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken
16、, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organizati
17、on Technical Barriers to Trade (TBT) Committee.1discard shall be made to secure freedom from injurious pipeand undue segregation.4.2 The material shall be forged as close as practical to thespecified shape and size.4.3 The finished product shall be a hot-worked forging asdefined by Specification A78
18、8/A788M.5. Machining5.1 Surfaces shall be machined as designated by the pur-chaser. Unmachined surfaces shall be sufficiently free of scaleto permit inspection.5.2 Machining may be performed either prior to or after heattreatment at the option of the manufacturer unless specified inaccordance with S
19、upplementary Requirement S1.6. Heat Treatment6.1 After forging and before reheating for heat treatment,the forgings shall be cooled in such a manner as to preventinjury and to accomplish transformation.6.2 All forgings shall be annealed, normalized, or normal-ized and tempered, but alternatively may
20、 be liquid quenchedand tempered when mutually agreed upon between the manu-facturer and the purchaser. When tempering is performed, itshall be at a subcritical temperature, but no less than 1100 F595 C.6.3 A multiple stage austenitizing procedure may be usedwhereby the forging is first fully austeni
21、tized and liquidquenched, followed by reheating within the intercritical tem-perature range to partially reaustenitize, and again liquidquenched. On completion of the austenitizing/quenchingcycles, tempering at a temperature between 1100 F 595 Cand the lower critical temperature shall follow.NOTE 2A
22、lthough liquid quenching from the austenitizing tempera-tures is more effective in enhancing impact properties, air cooling from theaustenitizing temperatures is also beneficial and may be used instead ofthe normalizing procedure in 6.2.7. Chemical Composition7.1 Heat AnalysisThe heat analysis obtai
23、ned from sam-pling in accordance with Specification A788/A788M shallcomply with Table 1 except that the additional features ofSupplementary Requirements S11 and S12 shall also apply asindividually specified in the ordering information.7.2 Product AnalysisThe purchaser may use the productanalysis pro
24、vision of Specification A788/A788M to obtain aproduct analysis from a forging representing each heat ormultiple heat.8. Mechanical Properties8.1 General RequirementsExcept when otherwise speci-fied in accordance with Supplementary Requirement S2, thematerial shall conform to the requirements for mec
25、hanicalproperties prescribed in Table 2 when tested in accordance withthe latest issue of Test Methods and Definitions A370 or TestMethods A1058 when the M suffix standard has been specified.The largest obtainable tension test specimen as specified in TestMethods and Definitions A370 or Test Methods
26、 A1058,asapplicable, shall be used.8.1.1 Except when otherwise specified in accordance withSupplementary Requirement S2, the longitudinal axis of thespecimens shall be parallel to the direction of major working ofthe forging. For upset-disc forgings, the longitudinal axis of thetest specimen shall b
27、e in the tangential direction.8.1.1.1 The longitudinal axis of the specimen shall belocated midway between the parallel surfaces of the testextension if added to the periphery of disks or midway betweenthe center and surface of solid forgings. For hollow forgings,the longitudinal axis of the specime
28、ns shall be located midwaybetween the center and outer surfaces of the wall. Whenseparately forged test blocks are employed as defined in 8.1.3,the tension test specimens shall be taken from a location thatrepresents the midwall of the heaviest section of the productionforgings. When specimens are r
29、equired from opposite ends,they shall be taken from the diagonal corners of an axial plane.8.1.2 Except as specified herein, tests for acceptance shallbe made after heat treatment has been completed. When theends of the cylindrical forgings are closed in by reforging, thecylindrical forgings may be
30、annealed, normalized, or normal-ized and tempered and tested prior to reforging. Afterreforging, the entire forging shall be reheat-treated in the samemanner and at the same temperature range as employed whenthe forging was heat-treated prior to certification testing.8.1.3 When mutually agreed upon
31、between manufacturerand purchaser, test specimens may be machined from aspecially forged block suitably worked and heat treated withthe production forgings. Such a special block shall be obtainedfrom an ingot, slab, or billet from the same heat used to makethe forgings it represents. This block shal
32、l receive essentiallythe same type of hot working and forging reduction as theproduction forgings; however, a longitudinally forged bar withdimensions not less than T by T by 3T may be used to representa ring forging. The dimension T shall be representative of theheaviest effective cross section of
33、the forging. For quenchedand tempered forgings for which tests are required at both endsby 8.2.2.3 and 8.2.2.4, separately forged test blocks are notallowed.TABLE 1 Chemical RequirementsComposition, %Grades 1 and 2 Grade 3 Grade 4Carbon, max 0.30 0.35 0.30Manganese 0.401.05 0.801.35 0.801.35Phosphor
34、us, max 0.025 0.025 0.025Sulfur, max 0.025 0.025 0.025Silicon 0.150.35 0.150.35 0.150.35TABLE 2 Tensile RequirementsGrade 1 Grades2 and 4Grade 3Tensile strength, min, ksi MPa 6085415585709548565575100515690Yield strength (0.2 % offset),min, ksi MPa302053625037.5260Elongation in 2 in. 62.5 mm,min, %2
35、32120181917Reduction of area, min, % 38 33 30A266/A266M 182NOTE 3In using separately forged test blocks, attention is drawn to theeffect of mass differences between the production forgings and the testblocks.8.2 Specific RequirementsThe number and location oftests are based on forging length, weight
36、, and heat treatment,and shall be as prescribed below. The length and weight to beused for this purpose shall be the shipped length and weight offorgings produced individually or the aggregate shipped lengthand weight of all pieces cut from a multiple forging.8.2.1 Annealed, Normalized, or Normalize
37、d and TemperedSteel Forgings:8.2.1.1 For forgings weighing 5000 lb 2250 kg or less atthe time of heat treatment, one tension test shall be taken fromone forging per heat in each heattreatment charge. When heattreatment is performed in continuous-type furnaces with suit-able temperature controls and
38、equipped with recording pyrom-eters so that complete heat-treatment records are available, atempering charge may be considered as any continuous run notexceeding an 8-h period.8.2.1.2 For forgings and forged bars weighing over 5000 lb2250 kg at the time of heat treatment, one tension test shall beta
39、ken from each forging.8.2.2 Quenched and Tempered Forgings:8.2.2.1 For quenched and tempered forgings weighing5000 lb 2250 kg or less at the time of heat treatment, but notexceeding 12 ft 3.7 m in length, one tension test shall betaken from one forging per heat in each heattreatment charge.When heat
40、 treatment is performed in continuous-type furnaceswith suitable temperature controls and equipped with recordingpyrometers so that complete heat-treatment records areavailable, a tempering charge may be considered as anycontinuous run not exceeding an 8-h period.8.2.2.2 For quenched and tempered fo
41、rgings and forged barsweighing over 5000 lb 2250 kg to 10 000 lb 4500 kg at thetime of heat treatment, but not exceeding 12 ft 3.7 m inlength, one tension test shall be taken from each forging.8.2.2.3 For quenched and tempered forgings and forged barsthat exceed 12 ft 3.7 m in length, one tension te
42、st shall betaken from each end of each forging.8.2.2.4 For quenched and tempered forgings and forged barsweighing more than 10 000 lb 4500 kg at the time of heattreatment, two tension test specimens shall be taken from eachforging. These shall be offset 180 from each other except thatif the length o
43、f the forging, excluding test prolongations,exceeds 12 ft 3.7 m, then one specimen shall be taken fromeach end of the forging.9. Repair Welding9.1 Repair welding of forgings is permissible only at theoption of the purchaser. If repair welding is performed, weldersand weld procedures shall be qualifi
44、ed in accordance withSection IX of the ASME Boiler and Pressure Vessel Code.10. Certification10.1 In addition to the mandatory certification requirementsof Specification A788/A788M, the heat treatment cycle datashall be included.11. Product Marking11.1 Each forging shall be identified in accordance
45、with theMarking Section of Specification A788/A788M. In addition,the forging shall be marked following the grade designation bythe letter “A” for annealed, “N” for normalized, “NT” fornormalized and tempered, and “S” for liquid quenched andtempered, as applicable.12. Keywords12.1 pressure vessel ser
46、vice; steel forgingscarbonSUPPLEMENTARY REQUIREMENTSOne or more of the following supplementary requirements shall apply only when specified by thepurchaser in the inquiry, contract, or order. Details of these supplementary requirements shall beagreed upon between the manufacturer and the purchaser.S
47、1. Rough Turning and BoringS1.1 The position of the rough turning and boring in thesequence of manufacturing operations shall be as specified bythe purchaser.S2. Alternative Tension Test OrientationS2.1 In lieu of the requirements of Section 8, the longitu-dinal axis of the test specimens shall be t
48、ransverse to thedirection of major working of the forging. The results shallconform with requirements of Table 2, with the exception ofthe ductility limits that shall be as follows:Grade 1 2 and 4 3Elongation in 2 in. 62.5 mm, min, % 20 18 19 17 18 16Reduction of area, min, % 30 25 25S3. Hydrostatic
49、 TestS3.1 Ahydrostatic pressure test shall be applied. The detailsof the test, including its position in the sequence of manufac-turing operations, shall be specified.A266/A266M 183S4. Magnetic Particle ExaminationS4.1 All accessible surfaces of the finished forging shall beexamined by a magnetic particle method. The method shall bein accordance with Practice A275/A275M. Acceptance limitsshall be as agreed upon between the manufacturer and thepurchaser.S5. Liquid Penetrant ExaminationS5.1 After
