1、Designation: A758/A758M 14Standard Specification forWrought-Carbon Steel Butt-Welding Piping Fittings withImproved Notch Toughness1This standard is issued under the fixed designation A758/A758M; the number immediately following the designation indicates the yearof original adoption or, in the case o
2、f 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.1. Scope*1.1 This specification covers wrought-carbon steel butt-welding seamless or welded fittings speci
3、ally processed toensure better notch toughness than that to be expected infittings manufactured to the requirements of SpecificationA234/A234M.1.1.1 Included are elbows, caps, tees, reducers, and othertype fittings covered by ASME B16.9.1.1.2 Heat treatment is required for all fittings.1.1.3 Fitting
4、s with mandatory radiographic examination ofwelds are included.1.1.4 Supplementary requirements are provided for usewhen additional testing or examination is desired.1.1.5 Cast fittings, and fittings formed from all weld metal,are not included.1.2 Several type of fittings are provided, as follows:Ty
5、peHeat TreatmentRequiredWeld SeamFinish (5.3.2)RadiographyRequired?30 normalize UW-35 no31 normalize UW-35 yes32 normalize UW-35 and ground flush yes40 normalize and temper UW-35 no41 normalize and temper UW-35 yes42 normalize and temper UW-35 and ground flush yes50 quench and temper UW-35 no51 quen
6、ch and temper UW-35 yes52 quench and temper UW-35 and ground flush yes1.3 It shall be the responsibility of the purchaser to deter-mine whether material meeting the requirements of this speci-fication is satisfactory for the service application.1.4 This specification is expressed in both inch-pound
7、unitsand SI units. However, unless the order specifies the applicable“M” specification designation (SI units), the material shall befurnished to inch-pound units.1.5 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. Within the text, theSI units are sh
8、own 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. Referenced Documents2.1 In addition to those reference documents liste
9、d inSpecification A960/A960M, the following list of standardsapply to this specification:2.2 ASTM Standards:2A234/A234M Specification for Piping Fittings of WroughtCarbon Steel and Alloy Steel for Moderate and HighTemperature ServiceA275/A275M Practice for Magnetic Particle Examination ofSteel Forgi
10、ngsA960/A960M Specification for Common Requirements forWrought Steel Piping FittingsE165 Practice for Liquid Penetrant Examination for GeneralIndustryE709 Guide for Magnetic Particle Testing2.3 ASME Boiler and Pressure Vessel Code (ASME Code):3Section VIII, Division 1Section IX2.4 ASME Standard:B16.
11、9 Standards for Steel Butt-Welding Fittings32.5 ASNT Standard:SNT-TC-1A Practice for Nondestructive Examination Per-sonnel Qualification and Certification43. Ordering Information3.1 See Specification A960/A960M.1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless St
12、eel 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 Purpose Applications.Current edition approved Oct. 1, 2014. Published October 2014. Originallyapproved in 1978. Las
13、t previous edition approved in 2013 as A758/A758M13.DOI: 10.1520/A0758_A0758M-14.2For 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
14、 onthe ASTM website.3Available from American Society of Mechanical Engineers (ASME), ASMEInternational Headquarters, Two Park Ave., New York, NY 10016-5990, http:/www.asme.org.4Available fromAmerican Society for Nondestructive Testing (ASNT), P.O. Box28518, 1711 Arlingate Ln., Columbus, OH 43228-051
15、8, http:/www.asnt.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. General Requirements4.1 Product furnished to this specification shall conform tothe requirements
16、 of Specification A960/A960M, including anysupplementary requirements that are indicated in the purchaseorder. 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
17、and Specification A960/A960M, this specificationshall prevail.5. Materials and Manufacture5.1 The steel shall be killed and shall be melted to a fineaustenitic grain size practice.5.2 The starting material shall be wrought and in the form ofblooms, billets, slabs, forgings, bars, plates, sheets, sea
18、mlesspipe or tube, or welded-with-filler-metal pipe or tube. Castproducts shall not be used.5.3 Any forming process, fusion-welding process, or com-bination of such processes, may be used.5.3.1 All welding shall be fusion-welded in accordance withthe requirements of Section IX of the ASME Boiler and
19、Pressure Vessel Code. Welding procedures, welders, and weld-ing operators shall be qualified in accordance with Section IXof the ASME Boiler and Pressure Vessel Code.5.3.2 All welded joints shall be finished in accordance withParagraph UW-35 of Section VIII, Division 1, of the ASMECode.5.3.3 Welded
20、joints of Type 32, 42, and 52 shall be groundflush.5.3.4 Welded joints of Types 31, 41, 51, 32, 42, and 52 shallbe examined by radiography in accordance with the require-ments of Paragraph UW-51 of Section VIII, Division 1, of theASME Code, and shall conform to the requirements ofParagraph UW-51.5.4
21、 Heat TreatmentAll fittings shall be heat treated sub-sequent to final welding and forming.5.4.1 Types 30, 31, and 32 fittings shall be normalized byuniformly heating to a temperature in the austenitizing range,but not to exceed 1700 F 925 C, and subsequently removedfrom the furnace and air-cooled i
22、ndividually to room tempera-ture.5.4.2 Types 40, 41, and 42 fittings shall be normalized inaccordance with 5.4.1. After normalizing, the fittings shall betempered by heating to a temperature in the range from 1100 Fto 1200 F 595 C to 675 C, soaking at that temperature for12 h minimum per 1 in. 25 mm
23、 of thickness, but not less than15 min, and then air-cooled to room temperature.5.4.3 Types 50, 51, and 52 fittings shall be quenched-and-tempered by uniformly heating to a temperature in the austen-itizing range, but not to exceed 1700 F 925 C, and thenquenching in a liquid media from the austeniti
24、zing temperatureto a temperature below 800 F 425 C. After quenching, thefittings shall be reheated to a temperature in the range from1100 F to 1250 F 595 C to 675 C, soaking at thattemperature for12 h minimum per 1 in. 25 mm of thickness,but not less than 15 min, and then air-cooled to roomtemperatu
25、re.6. Chemical Composition6.1 Heat or Cast AnalysisThe results shall conform to therequirements for the applicable grade as specified in Table 1.6.2 Product AnalysisThe purchaser may make a productanalysis on products made to this specification in accordancewith Specification A960/A960M.6.3 The stee
26、l shall not contain any unspecified elements forthe ordered grade to the extent that it conforms to therequirements of another grade for which that element is aspecified element having a required minimum content.7. Mechanical Requirements7.1 Tensile Requirements:7.1.1 The fittings, as represented by
27、 tensile test specimenstaken subsequent to final heat treatment, shall conform to therequirements for the applicable grade as specified in Table 2.7.1.2 Number and Location of Specimens:7.1.2.1 LotFor tension testing, a lot shall consist of thefittings from a heat, in each heat treatment charge, wit
28、hnominal wall thicknesses within14 in. 6 mm of the nominalthickness of the test specimen. In addition, for Types 32, 42,and 52, the lot definition shall include each heat or lot of weldmetal. If heat treatment is performed in a continuous orbatch-type furnace controlled within a range of plus-or-min
29、us25 F 14 C and equipped with calibrated thermocouples andrecording pyrometers, and records of heat treatment aremaintained, all fittings heat treated in such a furnace areconsidered to be in one charge. For furnaces not so equippedand controlled, each batch constitutes a charge.7.1.2.2 Representati
30、ve Test PieceFor instances in whichthe tension test specimen cannot be obtained from a fitting dueto size limitations, a representative test piece may be used. Thetest piece shall be from the same heat and shall be heat treatedin the same heat treatment batch or charge as the fittings itrepresents,
31、and shall have had approximately the same amountof working as the fittings. In addition, for fittings manufacturedfrom bars, plate, or forgings, the test piece shall have across-section equal to or larger than the greatest cross-sectionof the fittings it represents. Test pieces representing fittings
32、TABLE 1 Chemical RequirementsElement Cast or HeatAnalysisCarbon, max, % 0.27Manganese, % 0.851.20Phosphorus, max, % 0.035Sulfur, max, % 0.035Silicon, % 0.150.30Vanadium, max, % 0.05Residual elementsA,BChromium, max, % 0.25Nickel, max, % 0.25Molybdenum, max, % 0.08Copper, max, % 0.35Lead, max, % 0.05
33、AIndividual limits of chromium, nickel, molybdenum, and copper may be exceededby 0.05 % provided that their total does not exceed 0.90 % in both the heat andproduct analysis.BThese are not to be added to the melt and shall only occur as a result ofunavoidable residuals from the melting stock.A758/A7
34、58M 142manufactured from pipe shall have a nominal outside diameterand wall thickness equal to that of the pipe from which thefitting was formed. Test pieces for fittings fabricated bywelding or formed from welded pipe shall be prepared with thesame welding procedure and from the same heat or lot of
35、 weldmetal as the fitting it represents.7.1.2.3 Types 30, 31, 40, 41, 50, and 51One base-metaltension test specimen shall be tested from each lot. For fittingsfabricated by welding, one transverse-weld tension test speci-men shall also be made from each lot. One traverse-weldtension test specimen sh
36、all also be required from each lot forfittings formed from welded pipe if the weld in the welded pipewas not tested in the same heat treatment condition as thefittings.7.1.2.4 Types 32, 42, and 52One base-metal and onetransverse-weld tension test specimen shall be tested from eachlot. Fittings fabri
37、cated by welding or formed from welded pipeshall be tested as in 7.1.2.3.7.1.2.5 Tension test specimens shall be taken from anintegral part of the fitting where practicable. All base-metaltension tests shall be conducted in the longitudinal direction.Weld metal specimens shall be taken transverse to
38、 the weld.7.1.2.6 Yield strength shall be determined either by the0.2 % offset method or the 0.5 % extension-under-load method.7.2 Transverse Guided Weld Bend TestsWelded FittingsOnly:7.2.1 Number of Tests:7.2.1.1 LotA lot shall be as defined in 7.1.2.1.7.2.1.2 One guided face-bend and one guided ro
39、ot-bend testshall be made to represent each lot for fittings with a nominalwall thickness of38 in. 10 mm and less. For fittings with anominal wall thickness greater than38 in. 10 mm, one guidedside-bend test shall be made to represent each lot.7.2.2 Test Specimen Location and OrientationFull thick-n
40、ess specimens shall be taken transverse to the weld, subse-quent to final heat treatment, in accordance with Section IX ofthe ASME Boiler and Pressure Vessel Code.7.2.3 RequirementThe guided-bend test specimen shallnot have any cracks or other open defects exceeding18 in. 3mm, measured in any direct
41、ion on the convex surface of thespecimen after bending. Cracks occurring on the corners of thespecimen during testing shall not be considered unless there isdefinite evidence that they result from slag inclusions or otherinternal defects.8. Dimensions8.1 Butt-welded fittings shall conform to the dim
42、ensionsand tolerances specified in ASME B16.9.9. Surface Finish, Appearance, and Corrosion Protection9.1 The requirements of Specification A960/A960M apply.10. Radiographic Examination10.1 Types 31, 32, 41, 42, 51, and 52 fittings shall have theentire length of each weld joint examined radiographica
43、lly inaccordance with Paragraph UW-51 of Section VIII, Division 1,of the ASME Boiler and Pressure Vessel Code.10.2 Radiographic examination may be performed prior tofinal heat treatment.10.3 Personnel performing radiographic examination shallbe qualified and certified in accordance with SNT-TC-1A-19
44、84, or with the approval of the purchaser, in accordance withanother nationally-accepted standard which covers the qualifi-cation and certification of radiographic examination personnel.11. Rework and Retreatment11.1 See Specification A960/A960M.11.2 Repair WeldingParent Metal:11.2.1 Repair welding
45、by the manufacturer is permissiblefor parts made to dimensional standards, in ASME or equiva-lent standards.11.2.2 Prior approval of the purchaser shall be required toweld repair special parts made to the purchasers requirements.11.2.3 Welding shall produce low hydrogen in the weld-ment.11.2.4 The p
46、roduct shall be heat treated in accordance withSection 5 after weld repair.12. Inspection12.1 The manufacturer shall afford the purchasers inspec-tors all reasonable facilities necessary to satisfy him that thematerial is being produced and furnished in accordance withthis specification. Inspection
47、by the purchaser shall not inter-fere unnecessarily with the manufacturers operations. All testsand inspections shall be made at the place of manufacture,unless otherwise agreed to.13. Rejection and Rehearing13.1 Material that fails to conform to the requirements ofthis specification may be rejected
48、. Rejection should be reportedto the producer or supplier promptly and in writing. In case ofdissatisfaction with the results of the test, the producer orsupplier may make claim for a rehearing.13.2 Fittings that develop defects in shop working orapplication operations may be rejected. Upon rejectio
49、n, themanufacturer shall be notified in writing.14. Certification14.1 Test reports are required for all fittings covered by thisspecification. Each test report shall meet the requirements forTABLE 2 Tensile RequirementsGrade 60 Grade 70Tensile strength, ksi MPa 60 to 85 415 to 585 70 to 95 485 to 635Yield strength,Amin, ksiMPa35 240 38 260Elongation in 2 in. 50 mm,min, %Longitudinal 30 27Transverse 22 20A0.2 % offset or 0.5 % EUL.A758/A758M 143certification in Specification A960/A960M as well as includet
