1、Designation:A420/A420M16Standard Specification forPiping Fittings of Wrought Carbon Steel and Alloy Steel forLow-Temperature Service1This standard is issued under the fixed designation A420/A420M;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 specification2covers wrought carbon steel andalloy steel fittings of seamless and welded cons
3、truction,cov-ered by the latest revision of ASME B16.9,ASME B16.11,MSS SP-79,MSS SP-83,MSS SP-95,and MSS SP-97.Fittings differing from these ASME and MSS standards shallbe furnished in accordance with Supplementary RequirementS58 of Specification A960/A960M.These fittings are for use inpressure pipi
4、ng and pressure vessel service at low tempera-tures.1.2 Optional supplementary requirements are provided forfittings where a greater degree of examination is desired.Whendesired,one or more of these supplementary requirements shallbe specified in the order.1.3 This specification is expressed in both
5、 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.1.4 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.Within the text,theSI uni
6、ts 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.Referenced Documents2.1 In addition to those Referenced Documents
7、listed inSpecification A960/A960M,the following list of standardsapply to this specification.2.2 ASTM Standards:3A370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA960/A960M Specification for Common Requirements forWrought Steel Piping FittingsA1058 Test Methods for Mechanical
8、 Testing of SteelProductsMetric2.3 ASME Standards:B 16.9 Factory-Made Wrought Steel Butt-Welding Fittings4B 16.11 Forged Steel Fittings,Socket-Welding Threaded4Section VIII Division 1,Pressure Vessels4Section IX2.4 MSS Standards:MSS SP-25 Standard Marking System for Valves,Fittings,Flanges,and Union
9、s5MSS SP-79 Socket Welding Reducer Inserts5MSS SP-83 Steel Pipe Unions,Socket-Welding andThreaded5MSS SP-95 Swage(d)Nipples and Bull Plugs5MSS SP-97 Integrally Reinforced Forged Branch OutletFittingsSocket Welding,Threaded and ButtweldingEnds2.5 ASNT Standards:SNT-TC-1ARecommended Practice for Nonde
10、structiveTesting Personnel Qualification and Certification63.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 any1This specification is under the jurisdiction
11、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 Purpose Applications.Current edition approved May 1,2016.Published May 2
12、016.Originallyapproved in 1958.Last previous edition approved in 2014 as A420/A420M 14.DOI:10.1520/A0420_A0420M-16.2For ASME Boiler and Pressure Vessel Code applications see related Specifi-cation SA-420 in Section II of that Code.3For referenced ASTM standards,visit the ASTM website,www.astm.org,or
13、contact 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 Engineers(ASME),ASMEInternational Headquarters,Two Park Ave.,New York,NY 10016-5990,http
14、:/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 Nondestructive Testing(ASNT),P.O.Box28518,1711 Arlingate Ln.,Columbus,OH 43228-0518,http:/www.asnt.org.*
15、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 States1 supplementary requirements that are indicated in the purchaseorder.Failure to comply with the general requirements ofSpecifica
16、tion A960/A960M constitutes non-conformance withthis specification.In case of conflict between the requirementsof this specification and Specification A960/A960M,thisspecification shall prevail.5.Material5.1 The starting material for fittings shall be fully killedsteel,consisting of forgings,bars,plates,sheet,and seamless orfusion welded tubular products with filler metal added andshall conform to the chemical requirements in Table 1.Thesteels shall be made using recognized melting practices nec