1、Designation:A774/A774M14Standard Specification forAs-Welded Wrought Austenitic Stainless Steel Fittings forGeneral Corrosive Service at Low and ModerateTemperatures1This standard is issued under the fixed designation A774/A774M;the number immediately following the designation indicates the yearof or
2、iginal 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.1.Scope*1.1 This specification covers five grades of as-welded,wrought austeni
3、tic stainless steel fittings for low-pressurepiping and intended for low and moderate temperatures andgeneral corrosive service.Users should note that certaincorrosive conditions may restrict the use of one or more grades.For applications requiring a product that requires heat treat-ment or full pre
4、ssure rating,refer to Specification A403/A403M.The term“fittings”applies to butt and socket weldingparts such as 45 and 90 elbows,tees,reducers,wyes,laterals,crosses,and stub ends.1.2 This specification covers as-welded fittings 3 through 48in.75 through 1225 mm in outside diameter and in nominalwal
5、l thicknesses 0.062 through 0.500 in.1.6 through 12.7mm.Table 1 and Table 2 list the common diameters andnominal thicknesses of fittings in this specification.1.3 This specification does not apply to cast fittings.Castaustenitic steel fittings are covered by Specification A351/A351M.1.4 Optional sup
6、plementary requirements are provided forfittings where a greater degree of examination is desired.Thesesupplementary requirements call for additional tests.Whendesired,one or more of these may be specified in the order.1.5 This specification is expressed in both inch-pound unitsand in SI units.Howev
7、er,unless the order specifies theapplicable“M”specification designation(SI units),the mate-rial shall be furnished to inch-pound units.1.6 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.Within the text,theSI units are shown in brackets.The values st
8、ated 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 listed inSpecification A960/A960M,the f
9、ollowing list of standardsapply to this specification:2.2 ASTM Standards:2A240/A240M Specification for Chromium and Chromium-Nickel Stainless Steel Plate,Sheet,and Strip for PressureVessels and for General ApplicationsA351/A351M Specification for Castings,Austenitic,forPressure-Containing PartsA403/
10、A403M Specification for WroughtAustenitic StainlessSteel Piping FittingsA960/A960M Specification for Common Requirements forWrought Steel Piping FittingsE527 Practice for Numbering Metals and Alloys in theUnified Numbering System(UNS)2.3 ASME Standard:Section IX ASME Boiler and Pressure Vessel Code3
11、2.4 MSS Standard:SP 43 Wrought Stainless Steel Butt Welding Fittings42.5 AWS Standards:A5.4 Corrosion-Resisting Chromium and Chromium-NickelSteel Covered Welding Electrodes5A5.9 Corrosion-Resisting Chromium and Chromium-NickelSteel Welding Rods and Bare Electrodes51This specification is under the ju
12、risdiction 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 Oct.1,2014.Publ
13、ished October 2014.Originallyapproved in 1980.Last previous edition approved in 2013 as A774/A774M 13.DOI:10.1520/A0774_A0774M-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,
14、refer to the standards Document Summary page 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 from Manufacturers Standardization Society of the Valve and FittingsIndustr
15、y(MSS),127 Park St.,NE,Vienna,VA 22180-4602,http:/www.mss-.5Available from American Welding Society(AWS),550 NW LeJeune Rd.,Miami,FL 33126,http:/www.aws.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohock
16、en,PA 19428-2959.United States1Copyright by ASTM Intl(all rights reserved);2.6 SAE Standard:J1086 Unified Numbering System for Metals and Alloys63.Ordering Information3.1 See Specification A960/A960M and the following:3.1.1 Dimensions(outside diameter and specified wallthickness,see Table 1 and Table 2),3.1.2 Grade(Table 3),and3.1.3 End use,if known.4.General Requirements4.1 Product furnished to this specification shall conform tothe requirements of Specification A960/A960M,including anysuppleme
