1、Designation: A234/A234M 10aUsed in USDOE-NE StandardsStandard Specification forPiping Fittings of Wrought Carbon Steel and Alloy Steel forModerate and High Temperature Service1This standard is issued under the fixed designation A234/A234M; the number immediately following the designation indicates t
2、he yearof original adoption or, in the case of revision, the year of last 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 De
3、partment of Defense.1. Scope*1.1 This specification2covers wrought carbon steel andalloy steel fittings of seamless and welded construction coveredby the latest revision of ASME B16.9, B16.11, MSS-SP-79,MSS-SP-83, MSS-SP-95, and MSS-SP-97. These fittings arefor use in pressure piping and in pressure
4、 vessel fabrication forservice at moderate and elevated temperatures. Fittings differ-ing from these ASME and MSS standards shall be furnished inaccordance with Supplementary Requirement S58 of Specifi-cation A960/A960M.1.2 Optional supplementary requirements are provided forfittings where a greater
5、 degree of examination is desired. Whendesired, one or more of these supplementary requirements maybe specified in the order.1.3 This specification does not cover cast welding fittings orfittings machined from castings. Cast steel welding fittings aregoverned by Specifications A216/A216M and A217/A2
6、17M.1.4 This specification is expressed in both inch-pound unitsand in SI units. However, unless the order specifies theapplicable “M” specification designation (SI units), the mate-rial shall be furnished to inch-pound units.1.5 The values stated in either SI units or inch-pound unitsare to be rega
7、rded separately as standard. Within the text, theSI units are shown in brackets. The values stated in eachsystem may not be exact equivalents; therefore, each systemshall be used independently of the other. Combining valuesfrom the two systems may result in non-conformance with thestandard.2. Refere
8、nced Documents2.1 In addition to those reference documents listed inSpecification A960/A960M, the following list of standardsapply to this specification.2.2 ASTM Standards:3A216/A216M Specification for Steel Castings, Carbon,Suitable for Fusion Welding, for High-Temperature Ser-viceA217/A217M Specif
9、ication for Steel Castings, MartensiticStainless and Alloy, for Pressure-Containing Parts, Suit-able for High-Temperature ServiceA960/A960M Specification for Common Requirements forWrought Steel Piping Fittings2.3 ASME Standards:4B16.9 Steel Butt-Welding FittingsB16.11 Forged Steel Fittings, Socket
10、Welding and Threaded2.4 ASME Boiler and Pressure Vessel Code:4Section V Nondestructive ExaminationSection VIII, Division 1, Pressure VesselsSection IX Welding Qualifications2.5 MSS Standards:5MSS-SP-25 Standard Marking System for Valves, Fittings,Flanges, and UnionsMSS-SP-79 Socket Welding Reducer I
11、nsertsMSS-SP-83 Steel Pipe Unions, Socket-Welding andThreadedMSS-SP-95 Swage(d) Nipples and Bull PlugsMSS-SP-97 Integrally Reinforced Forged Branch OutletFittingsSocket Welding, Threaded and ButtweldingEnds2.6 ASNT Standard:6SNT-TC-1A Recommended Practice for NondestructiveTesting Personnel Qualific
12、ation and Certification1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.22 on Steel Forgings and Wrought Fittings for Piping Applications and BoltingMaterials for Piping and Special Pur
13、pose Applications.Current edition approved Oct. 1, 2010. Published November 2010. Originallyapproved in 1940. Last previous edition approved in 2010 as A234/A234M10.DOI: 10.1520/A0234_A0234M-10a.2For ASME Boiler and Pressure Vessel Code applications see related Specifi-cation SA-234 in Section II of
14、 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.4Available from American Society of Mechanical Eng
15、ineers (ASME), ASMEInternational Headquarters, Three Park Ave., New York, NY 10016-5990, http:/www.asme.org.5Available from Manufacturers Standardization Society of the Valve and FittingsIndustry (MSS), 127 Park St., NE, Vienna, VA 22180-4602, http:/www.mss-.6Available fromAmerican Society for Nonde
16、structive Testing (ASNT), P.O. Box28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http:/www.asnt.org.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.2.7 AWS Specif
17、ications7A5.5/A5.5M Specification for Low-Alloy Steel Electrodesfor Shielded Metal Arc WeldingA5.23/A5.23M Specification for Low-Alloy Steel Elec-trodes and Fluxes for Submerged Arc WeldingA5.28/A5.28M Specification for Low-Alloy Steel Elec-trodes for Gas Shielded Arc WeldingA5.29/A5.29M Low-Alloy S
18、teel Electrodes for Flux CoredArc Welding3. Ordering Information3.1 See Specification A960/A960M.4. General Requirements4.1 Product furnished to this specification shall conform tothe requirements of Specification A960/A960M, including anysupplementary requirements that are indicated in the purchase
19、order. Failure to comply with the requirements of SpecificationA960/A960M constitutes non-conformance with this specifi-cation. In case of a conflict between the requirements of thisspecification and SpecificationA960/A960M, this specificationshall prevail.5. Materials5.1 The material for fittings s
20、hall consist of killed steel,forgings, bars, plates, sheet, and seamless or fusion-weldedtubular products with filler metal added and shall conform tothe chemical requirements of Table 1. Unless otherwise speci-fied for carbon steel plates and sheet, the steel may be made toeither coarse grain or fi
21、ne grain practice. Grade WP9 shall bemade to fine grain practice.5.2 A starting material specification that specifically re-quires the addition of any element beyond those listed for thematerials in Table 1 for the applicable grade of material is notpermitted. This does not preclude the use of deoxi
22、dizers or thejudicious use of elements for grain size control.6. Manufacture6.1 Forging or shaping operations may be performed byhammering, pressing, piercing, extruding, upsetting, rolling,bending, fusion welding, machining, or by a combination of7Available from American Welding Society (AWS), 550
23、NW LeJeune Rd.,Miami, FL 33126, http:/www.aws.org.TABLE 1 Chemical RequirementsNOTE 1All requirements are maximum unless otherwise indicated.NOTE 2Where an ellipsis (.) appears in this table, there is no requirement.Grade andMarkingSymbolAComposition, %Carbon ManganesePhospho-rus, maxSulfur,maxSilic
24、on Chromium Molybdenum Nickel Copper OthersWPBB,C,D,E,F0.30 max 0.291.06 0.050 0.058 0.10 min 0.40 max 0.15 max 0.40 max 0.40 max Vanadium 0.08 maxWPCC,D,E,F0.35 max 0.291.06 0.050 0.058 0.10 min 0.40 max 0.15 max 0.40 max 0.40 max Vanadium 0.08 maxWP1 0.28 max 0.300.90 0.045 0.045 0.100.50 . . . 0.
25、440.65 . . . . . . . . .WP12 CL1, 0.050.20 0.300.80 0.045 0.045 0.60 max 0.801.25 0.440.65 . . . . . . . . .WP12 CL2 .WP11 CL1 0.050.15 0.300.60 0.030 0.030 0.501.00 1.001.50 0.440.65 . . . . . . . . .WP11 CL2, 0.050.20 0.300.80 0.040 0.040 0.501.00 1.001.50 0.440.65 . . . . . . . . .WP11 CL3 .WP22
26、CL1, 0.050.15 0.300.60 0.040 0.040 0.50 max 1.902.60 0.871.13 . . . . . . . . .WP22 CL3 .WP5 CL1, 0.15 max 0.300.60 0.040 0.030 0.50 max 4.06.0 0.440.65 . . . . . . . . .WP5 CL3 .WP9 CL1,WP9 CL30.15 max 0.300.60 0.030 0.030 1.00 max 8.010.0 0.901.10 . . . . . . . . .WPR 0.20 max 0.401.06 0.045 0.050
27、 . . . . . . . . . 1.602.24 0.751.25 . . .WP91 0.080.12 0.300.60 0.020 0.010 0.200.50 8.09.5 0.851.05 0.40 max . . . Vanadium 0.180.25Columbium 0.060.10Nitrogen 0.030.07Aluminum 0.02 maxGTitanium 0.01 maxGZirconium 0.01 maxGWP911 0.090.13 0.300.60 0.020 0.010 0.100.50 8.59.5 0.901.10 0.40 max . . .
28、Vanadium 0.180.25Columbium 0.0600.10Nitrogen 0.040.09Aluminum 0.02 maxGBoron 0.00030.006Tungsten 0.901.10Titanium 0.01 maxGZirconium 0.01 maxGAWhen fittings are of welded construction, the grade and marking symbol shown above shall be supplemented by letter “W”.BFittings made from bar or plate may h
29、ave 0.35 max carbon.CFittings made from forgings may have 0.35 max carbon and 0.35 max silicon with no minimum.DFor each reduction of 0.01 % below the specified carbon maximum, an increase of 0.06 % manganese above the specified maximum will be permitted, up to amaximum of 1.35 %.EThe sum of Copper,
30、 Nickel, Chromium, and Molybdenum shall not exceed 1.00 %.FThe sum of Chromium and Molybdenum shall not exceed 0.32 %.GApplies both to heat and product analyses.A234/A234M 10a2two or more of these operations. The forming procedure shallbe so applied that it will not produce injurious imperfections i
31、nthe fittings.NOTE 1Fittings NPS-4 and under may be machined from hot-forgedor rolled, cold-sized, and straightened bar stock having the chemicalcomposition of the Grade in Table 1 and the mechanical properties of theGrade in Table 2. Heat treatment shall be in accordance with Section 7.Allcaps mach
32、ined from bar stock shall be examined by liquid penetrant ormagnetic particle in accordance with S52 or S53 in SpecificationA960/A960M.6.2 All welds including welds in tubular products fromwhich fittings are made shall be (1) made by welders, weldingoperators, and welding procedures qualified under
33、the provi-sions of ASME Section IX,(2) heat treated in accordance withSection 7 of this specification, and (3) radiographically exam-ined throughout the entire length of each weld in accordancewith Article 2, ASME Section V with acceptance limits inaccordance with Paragraph UW-51 of ASME Section VII
34、I,Division 1 of the ASME Boiler min % in 2 in. 50 mm30 20A28 . . .Rectangular specimen for wall thickness less than516 in. 7.94 mm;min % in 2 in. 50 mm (12-in. 12.7-mm wide specimen)BBB. . .AWPB and WPC fittings manufactured from plate shall have a minimum elongation of 17 %.BFor each132 in. 0.79 mm
35、 decrease in wall thickness below516 in. 7.94 mm, a deduction of 1.5 % for longitudinal and 1.0 % for transverse from the values shownabove is permitted. The following table gives the minimum value for various wall thicknesses.Wall ThicknessGradesAll Grades except WPR, WP91 and WP911 WPR WP91 and WP
36、911in. mm Longitudinal Transverse Longitudinal Longitudinal516 (0.312) 7.94 30.0 20.0 28.0 20932 (0.281) 7.14 28.5 19.0 26.5 1914 (0.250) 6.35 27.0 18.0 25.0 18732 (0.219) 5.56 25.5 . . . 23.5 17316 (0.188) 4.76 24.0 . . . 22.0 16532 (0.156) 3.97 22.5 . . . 20.5 1518 (0.125) 3.17 21.0 . . . 19.0 143
37、32 (0.094) 2.38 19.5 . . . 17.5 13116 (0.062) 1.59 18.0 . . . 16.0 12NoteThis table gives the computed minimum % elongation value for each132 in. 0.79 mm decrease in wall thickness. Where the wall thickness lies between twovalues above, the minimum elongation value is determined by the following equ
38、ations:Direction of Test EquationLongitudinal E=48t + 15.00Transverse E=32t + 10.00where:E = elongation in 2 in. or 50 mm, %, andt = actual thickness of specimen, in. mm.A234/A234M 10a3and WPR may be performed either prior to or after forming.NDE of welds in Grades WP5, WP9, WP91, WP911, WP22Class 1
39、, and WP22 Class 3 shall be done after forming.6.2.1 All welds in WP91 shall be made with one of thefollowing welding processes and consumables: SMAW, A5.5/A5.5M E90XX-B9; SAW, A5.23/A5.23M EB9 + flux; GTAW,A5.28/A5.28M ER90S-B9; and FCAWA5.29/A5.29M E91T1-B9. In addition, the Ni+Mn content of all w
40、elding consumablesused to fabricate WP91 fittings shall not exceed 1.0 %.6.3 Personnel performing NDE examinations shall be quali-fied in accordance with SNT-TC-1A.6.4 The welded joints of the fittings shall be finished inaccordance with the requirements of Paragraph UW-35 (a)ofASME Section VIII, Di
41、vision 1.6.5 All butt-weld tees manufactured by cold-forming meth-od(s) shall be liquid penetrant or magnetic particle examinedby one of the methods specified in Supplementary RequirementS52 or S53 in Specification A960/A960M. This examinationshall be performed after final heat treat. Only the side
42、wall areaof the tees need be examined. This area is defined by a circlethat covers the area from the weld bevel of the branch outlet tothe center line of the body or run. Internal and external surfacesshall be examined when size permits accessibility. No cracksshall be permitted. Other imperfections
43、 shall be treated inaccordance with Section 14 on Surface Quality. After theremoval of any crack, the tee(s) shall be re-examined by theoriginal method. Acceptable tees shall be marked with thesymbol PT or MT, as applicable, to indicate compliance.6.6 Stubends may be produced with the entire lap add
44、ed bythe welding of a ring, made from plate or bar of the same alloygrade and composition, to the outside of a straight section ofpipe, provided the weld is double welded, is a full penetrationjoint, satisfies the requirements of 6.2 for qualifications and7.3.3 for post weld heat treatment.7. Heat T
45、reatment7.1 Heat Treatment ProceduresFittings, after forming atan elevated temperature, shall be cooled to a temperaturebelow the critical range under suitable conditions to preventinjurious defects caused by too rapid cooling, but in no casemore rapidly than the cooling rate in still air. Heat trea
46、tmenttemperatures specified are metal (part) temperatures. Heat-treated fittings shall be treated according to paragraph 7 inSpecification A960/A960M.7.2 WPB, WPC, and WPR Fittings:7.2.1 Hot-formed WPB, WPC, and WPR fittings uponwhich the final forming operation is completed at a temperatureabove 11
47、50 F 620 C and below 1800 F 980 C need notbe heat treated provided they are cooled in still air.7.2.2 Hot-formed or forged WPB, WPC, and WPR fittingsfinished at temperature in excess of 1800 F 980 C shallsubsequently be annealed, normalized, or normalized andtempered. Hot-forged fittings NPS 4 or sm
48、aller need not beheat treated.7.2.3 WPB, WPC, and WPR fittings over NPS 12, producedby locally heating a portion of the fitting stock to anytemperature for forming, shall be subsequently annealed,normalized, or normalized and tempered. Fittings such aselbows, tees, header tees, reducers and lap join
49、t stub ends witha carbon content less than 0.26 %, NPS 12 and under, shall notrequire heat treatment after forming a locally heated portion ofthe fitting.7.2.4 Cold-formed WPB, WPC, and WPR fittings, uponwhich the final forming operation is completed at a temperaturebelow 1150 F 620 C, shall be normalized, or shall be stressrelieved at 1100 to 1275 F 595 to 690 C.7.2.5 WPB, WPC, and WPR fittings produced by fusionwelding and having a nominal wall thickness at the
