Designation:A437/A437M−15StandardSpecificationforStainlessandAlloy-SteelTurbine-TypeBoltingSpeciallyHeatTreatedforHigh-TemperatureService1ThisstandardisissuedunderthefixeddesignationA437/A437M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thisspecification2coversstainlessandalloy-steelbolt-ingmaterialandboltingcomponentsspeciallyheattreatedforhigh-temperatureservice,suchassteamturbine,gasturbine,andsimilaruses.SeeSpecificationA962/A962Mforthedefinitionofbolting.Thismaterialrequiresspecialprocessingandshouldnotbeusedingeneral-purposeapplications.Bolt-ingfurnishedasbarsshallbehotwroughtandmaybefurtherprocessedbycenterlessgrindingorbycolddrawing.1.2Thehigh-temperaturepropertiesoftheboltingmaterialsandcomponentscoveredbythisspecificationaredependentuponspecialheattreatment,whichisrequired.Althoughthehigh-temperaturepropertiesarenotspecified,theyareimpliedbycontrolofthechemistry,heattreatment,androom-temperaturepropertiesoftheboltingmaterial.1.3Threelevelsofboltingstrengtharecovered,designatedGradesB4B,B4C,andB4D.1.4Thefollowingreferencedgeneralrequirementsarein-dispensableforapplicationofthisspecification:SpecificationA962/A962M.1.5Supplementaryrequirementsareprovidedforuseattheoptionofthepurchaser.Thesupplementaryrequirementsshallapplyonlywhenspecifiedindividuallybythepurchaserinthepurchaseorderorcontract.1.6Thisspecificationisexpressedinbothinch-poundunitsandinSIunits;however,unlessthepurchaseorderorcontractspecifiestheapplicableMspecificationdesignation(SIunits),theinch-poundunitsshallapply.1.7ThevaluesstatedineitherSIunitsorinch-poundunitsaretoberegardedseparatelyasstandard.Withinthetext,theSIunitsareshowninbrackets.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshallbeusedindependentlyoftheother.Combiningvaluesfromthet...
