ASTM_A_437_-_A_437M_-_15.pdf

Designation:A437/A437M15Standard Specification forStainless and Alloy-Steel Turbine-Type Bolting SpeciallyHeat Treated for High-Temperature Service1This standard is issued under the fixed designation A437/A437M;the number immediately following the designation indicates the yearof original 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 specification2covers stainless and alloy-steel bolt-ing material and bolting components specially heat treated forhigh-temperature service,such as steam turbine,gas turbine,and similar uses.See Specification A962/A962M for thedefinition of bolting.This material requires special processingand should not be used in general-purpose applications.Bolt-ing furnished as bars shall be hot wrought and may be furtherprocessed by centerless grinding or by cold drawing.1.2 The high-temperature properties of the bolting materialsand components covered by this specification are dependentupon special heat treatment,which is required.Although thehigh-temperature properties are not specified,they are impliedby control of the chemistry,heat treatment,and room-temperature properties of the bolting material.1.3 Three levels of bolting strength are covered,designatedGrades B4B,B4C,and B4D.1.4 The following referenced general requirements are in-dispensable for application of this specification:SpecificationA962/A962M.1.5 Supplementary requirements are provided for use at theoption of the purchaser.The supplementary requirements shallapply only when specified individually by the purchaser in thepurchase order or contract.1.6 This specification is expressed in both inch-pound unitsand in SI units;however,unless the purchase order or contractspecifies the applicable M specification designation(SI units),the inch-pound units shall apply.1.7 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 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 ASTM Standards:3A962/A962M Specification for Common Requirements forBolting Intended for Use at Any Temperature from Cryo-genic to the Creep RangeE292 Test Methods for Conducting Time-for-Rupture NotchTension Tests of MaterialsE112 Test Methods for Determining Average Grain Size3.Ordering Information3.1 It shall be the responsibility of the purchaser to specifyall requirements necessary for product under this specification.Such requirements to be considered include,but are not limitedto,the following:3.1.1 Specification designation,grade,issue date,and revi-sion letter,3.1.2 Quantity(weight or number of pieces),3.1.3 Description(bars,bolts,nuts,etc.),3.1.4 Dimensions,3.1.5 Finish,and3.1.6 Impact testing of nuts,if required(see Section 8).4.Common Requirements4.1 Bolting materials and bolting components supplied tothis specification shall conform to the requirements of Speci-fication A962/A962M.These requirements include testmethods,finish,thread dimensions,macroetch(Grade B4Donly),marking,certification,optionalsupplementaryrequirements,and others.Failure to comply with the require-ments of Specification A962/A962M constitutes nonconfor-mance with this specification.In case of conflict between thisspecification and Specification A962/A962M,this specificationshall prevail.1This specification is under the jurisdiction 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 Nov.1,2015.Published November 2015.Originallyapproved in 1959.Last previous edition approved in 2012 as A437/A437M12.DOI:10.1520/A0437_A0437M-15.2For ASME Boiler and Pressure Vessel Code applications see related Specifi-cation SA-437 in Section II of that code.3For 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 onthe ASTM website.*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 5.Heat Treatment5.1 Grades B4B and B4C shall be heated to a temperaturerange of 1875 to 1925 F 1025 to 1050 C and liquidquenched to below 600 F 316 C.The material Grades B4Band B4C shall then be uniformly reheated for tempering at atempering temperature at least 100 F 55 C higher than theproposed operating temperature but not less than 1150 F 620C,then air or furnace cooled