Designation:A508/A508M−17StandardSpecificationforQuenchedandTemperedVacuum-TreatedCarbonandAlloySteelForgingsforPressureVessels1ThisstandardisissuedunderthefixeddesignationA508/A508M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope*1.1Thisspecification2coversquenchedandtemperedvacuum-treatedcarbonandalloysteelforgingsforpressurevesselssuchasthoseusedinreactorsystems.Specifically,itcoversforgingsforvesselclosures,shells,flanges,tubesheets,rings,heads,andsimilarparts.1.2Allgradesareconsideredweldableunderpropercondi-tions.Weldingtechniqueisoffundamentalimportance,anditispresupposedthatweldingprocedureandinspectionwillbeinaccordancewithapprovedmethodsforthegradeofmaterialused.1.3ThevaluesstatedineitherSIunitsorinch-poundunitsaretoberegardedseparatelyasstandard.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshallbeusedindependentlyoftheother.Combiningvaluesfromthetwosystemsmayresultinnon-conformancewiththestandard.1.4Unlesstheorderspecifiestheapplicable“M”specifica-tiondesignation,thematerialshallbefurnishedtotheinch-poundunits.NOTE1—Grades1and1Aarecomposedofdifferentchemistriesbuthavethesamemechanicalrequirements.NOTE2—Designationshavebeenchangedasfollows:CurrentFormerlyGrade1Class1Grade1AClass1AGrade2Class1Class2Grade2Class2Class2AGrade3Class1Class3Grade3Class2Class3AGrade4NClass1Class4Grade4NClass2Class4AGrade4NClass3Class4BGrade5Class1Class5Grade5Class2Class5AGrade22Class3Class22BGrade22Classes4,5,6,and7Grade3VClass3V1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriorto...
