1、Designation: A 266/A 266M 03aStandard Specification forCarbon Steel Forgings for Pressure Vessel Components1This standard is issued under the fixed designation A 266/A 266M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year
2、of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This specification2covers four g
3、rades 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
4、is desired. These shall applyonly when specified individually by the purchaser in the order.1.3 The values stated in either inch-pound units or SI(metric) units are to be regarded separately as the standard.Within the text and tables, the SI units are shown in brackets.The values stated in each syst
5、em are not exact equivalents;therefore, each system must be used independently of the other.Combining values from the two systems may result in noncon-formance with the specification.1.4 Unless the order specifies the applicable “M” specifica-tion designation, the material shall be furnished to the
6、inch-pound units.2. Referenced Documents2.1 ASTM Standards:3A 275/A 275M Test Method for Magnetic Particle Exami-nation of Steel ForgingsA 370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA 788 Specification for Steel Forgings, General Require-mentsE 112 Test Methods for Deter
7、mining the Average GrainSizeE 165 Test Method for Liquid Penetrant ExaminationE 381 Method of Macroetch Testing Steel Bars, Billets,Blooms, and Forgings2.2 Other Standard:ASME Boiler and Pressure Vessel Code, Section IX, Weld-ing Qualifications43. Ordering Information and General Requirements3.1 In
8、addition to the ordering information required bySpecification A 788, the purchaser shall include with theinquiry and order a detailed drawing, sketch, or writtendescription of the forging.3.2 Material supplied to this specification shall conform tothe requirements of Specification A 788, which outli
9、nes addi-tional ordering information, manufacturing requirements, test-ing and retesting methods and procedures, marking, certifica-tion, product analysis variations, and additional supplementaryrequirements.3.3 If the requirements of this specification are in conflictwith the requirements of Specif
10、ication A 788, the requirementsof this specification shall prevail.3.4 For hubbed flanges and tube sheets ordered for ASMEBoiler and Pressure Vessel Code application, SupplementaryRequirement S12 of Specification A 788 shall be specified inaddition to Supplementary Requirement S8 of this specifica-t
11、ion.4. Materials and Manufacture4.1 The steel shall be made in accordance with the MeltingProcess Section of Specification A 788. A sufficient discardshall be made to secure freedom from injurious pipe and unduesegregation.4.2 The material shall be forged as close as practical to thespecified shape
12、and size.4.3 The finished product shall be a hot-worked forging asdefined by Specification A 788.1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel, and Related Alloys and is the direct responsibility of SubcommitteeA01.06 on Steel Forgings and Billets.Curre
13、nt edition approved Sept. 10, 2003. Published October 2003. Originallyapproved in 1943. Last previous edition approved in 2003 as A 266/A 266M03.2For ASME Boiler and Pressure Vessel Code applications, see related Specifi-cation SA266/ SA266M in Section II of that code.3For referenced ASTM standards,
14、 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.4Available from the American Society of Mechanical Engineers, 345 East 47thSt., New York, NY
15、 10017.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5. Machining5.1 Surfaces shall be machined as designated by the pur-chaser. Unmachined surfaces shall be suffici
16、ently 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 Supplementary Requirement S1.6. Heat Treatment6.1 After forging and before reheating for heat treatment,the forgings shal
17、l 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 be liquid quenchedand tempered when mutually agreed upon between the manu-facturer and the purchaser. When tempering is
18、 performed, itshall be at a subcritical temperature, but no less than 1100F595C.6.3 A multiple stage austenitizing procedure may be usedwhereby the forging is first fully austenitized and liquidquenched, followed by reheating within the intercritical tem-perature range to partially reaustenitize, an
19、d again liquidquenched. On completion of the austenitizing/quenchingcycles, tempering at a temperature between 1100F 595Cand the lower critical temperature shall follow.NOTE 2Although liquid quenching from the austenitizing tempera-tures is more effective in enhancing impact properties, air cooling
20、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 obtained from sam-pling in accordance with Specification A 788 shall comply withTable 1 except that the additional features of Su
21、pplementaryRequirements S11 and S12 shall also apply as individuallyspecified in the ordering information.7.2 Product AnalysisThe purchaser may use the productanalysis provision of Specification A 788 to obtain a productanalysis from a forging representing each heat or multiple heat.8. Mechanical Pr
22、operties8.1 General RequirementsExcept when otherwise speci-fied in accordance with Supplementary Requirement S2, thematerial shall conform to the requirements for mechanicalproperties prescribed in Table 2 when tested in accordance withthe latest issue of Test Methods and Definitions A 370. Thelarg
23、est obtainable tension test specimen as specified in TestMethods and Definitions A 370 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 upse
24、t-disc forgings, the longitudinal axis of thetest specimen shall be 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
25、forgings. For hollow forgings,the longitudinal axis of the specimens 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 th
26、e heaviest section of the productionforgings. When specimens are required 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 fo
27、rgings are closed in by reforging, thecylindrical forgings may be annealed, normalized, or normal-ized and tempered and tested prior to reforging. After reforg-ing, the entire forging shall be reheat-treated in the samemanner and at the same temperature range as employed whenthe forging was heat-tre
28、ated prior to certification testing.8.1.3 When mutually agreed upon 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 t
29、he same heat used to makethe forgings it represents. This block shall 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
30、T shall be representative of theheaviest effective cross section of 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.NOTE 3In using separately forged test blocks, attention is drawn tothe effe
31、ct of mass differences between the production forgings and the testblocks.8.2 Specific RequirementsThe number and location oftests are based on forging length, weight, and heat treatment,and shall be as prescribed below. The length and weight to beused for this purpose shall be the shipped length an
32、d weight offorgings produced individually or the aggregate shipped lengthand weight of all pieces cut from a multiple forging.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 0.801.35Phosphorus, max 0.025 0.025 0.025Sulfur
33、, 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, ksiMPa6085415585709548565575100515690Yield strength (0.2 % offset),min, ksi MPa302053625037.5260Elongation in 2 in. or 50mm, min, %23 20 19Reduction of area, min, %
34、 38 33 30A 266/A 266M 03a28.2.1 Annealed, Normalized, or Normalized 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
35、 continuous-type furnaces with suit-able temperature controls and 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 lb
36、2250 kg at the time of heat treatment, one tension test shall betaken from each forging.8.2.2 Quenched and Tempered Forgings:8.2.2.1 For quenched and tempered forgings weighing 5000lb 2250 kg or less at the time of heat treatment, but notexceeding 12 ft 3.7 m in length, one tension test shall betake
37、n from one forging per heat in each heattreatment charge.When heat treatment is performed in continuous-type furnaceswith suitable temperature controls and equipped with recordingpyrometers so that complete heat-treatment records are avail-able, a tempering charge may be considered as any continuous
38、run not exceeding an 8-h period.8.2.2.2 For quenched and tempered forgings 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 forgi
39、ngs and forged barsthat exceed 12 ft 3.7 m in length, one tension test 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.
40、These shall be offset 180 from each other except thatif the length of 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 repa
41、ir welding is performed, weldersand weld procedures shall be qualified in accordance withSection IX of the ASME Boiler and Pressure Vessel Code.10. Certification10.1 In addition to the mandatory certification requirementsof Specification A 788, the heat treatment cycle data shall beincluded.11. Prod
42、uct Marking11.1 Each forging shall be identified in accordance with theMarking Section of Specification A 788. In addition, theforging shall be marked following the grade designation by theletter “A” for annealed, “N” for normalized, “NT” for normal-ized and tempered, and “S” for liquid quenched and
43、 tempered,as applicable.12. Keywords12.1 pressure vessel service; 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 shal
44、l beagreed upon between the manufacturer and the purchaser.S1. 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 Sectio
45、n 8, the longitu-dinal axis of the test specimens shall be transverse 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. 50 mm, min, % 20 19 18
46、Reduction of area, min, % 30 25 25S3. Hydrostatic TestS3.1 A hydrostatic pressure test shall be applied. The detailsof the test, including its position in the sequence of manufac-turing operations, shall be specified.S4. Magnetic Particle ExaminationS4.1 All accessible surfaces of the finished forgi
47、ng shall beexamined by a magnetic particle method. The method shall bein accordance with Test Method A 275/A 275 M. Acceptancelimits shall be as agreed upon between the manufacturer andthe purchaser.S5. Liquid Penetrant ExaminationS5.1 After forgings have been heat treated by liquid quench-ing and t
48、empering, all accessible surfaces shall be inspected forquench cracks by the liquid penetrant method in accordancewith Test Method E 165 as an alternative to magnetic particleexamination.S6. Macroetch TestS6.1 A sample forging shall be sectioned and etched toshow flow lines and internal imperfection
49、s. The test shall beconducted in accordance with Method E 381. Details of the testshall be agreed upon between the manufacturer and thepurchaser.A 266/A 266M 03a3S7. Product AnalysisS7.1 A product analysis in accordance with Section 7 shallbe made from one randomly selected forging representing eachsize and shape of forging on the order. If the analysis fails tocomply, each forging shall be checked or the lot rejected. Allresults shall be reported to the purchaser.S8. Specimen Location on Forged HubsS8.1 Forged h
