ASTM_A_983_-_A_983M_-_06_2016.pdf

Designation:A983/A983M06(Reapproved 2016)Standard Specification forContinuous Grain Flow Forged Carbon and Alloy SteelCrankshafts for Medium Speed Diesel Engines1This standard is issued under the fixed designation A983/A983M;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 specification covers continuous grain flow forgedcarbon and alloy steel crankshafts for medium speed diesel andnatural gas engines.1.2 The steel used in the manufacture of the forgings isrequired to be vacuum degassed.1.3 The choice of steel composition grade for a givenstrength class is normally made by the forging supplier,unlessotherwise specified by the purchaser.1.4 Provision is made for treatment of designated surfacesof the crankshaft to provide enhanced fatigue strength,or wearresistance,or both.1.5 Except as specifically required in this specification,allprovisions of Specification A788/A788M apply.1.6 Unless the order specifies the applicable“M”specifica-tion designation,the material shall be furnished to the inch-pound units.1.7 The values stated in either inch-pound units or SI(metric)units are to be regarded separately as standard.Withinthe text and tables the SI units are shown in brackets.Thevalues stated in each system are not exact equivalents;therefore,each system shall be used independently of the other.Combining values from the two systems may result in noncon-formance with the specification.2.Referenced Documents2.1 ASTM Standards:2A370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA503/A503M Specification for Ultrasonic Examination ofForged CrankshaftsA788/A788M Specification for Steel Forgings,General Re-quirementsA966/A966M Practice for Magnetic Particle Examination ofSteel Forgings Using Alternating CurrentA986/A986M Specification for Magnetic Particle Examina-tion of Continuous Grain Flow Crankshaft ForgingsE45 Test Methods for Determining the Inclusion Content ofSteelE112 Test Methods for Determining Average Grain SizeE340 Practice for Macroetching Metals and Alloys2.2 Other Standards:AWS D1.1 Structural Welding Code3DIN 50 6024JIS G 0555 Microscopic Testing Method for the Non-Metallic Inclusions in Steel53.Ordering Information3.1 In addition to the ordering requirements of SpecificationA788/A788M,the following items should be included:3.2 Choice of mechanical property class from Table 1.3.3 Choice of chemical composition Grade from Table 2 ifthis purchaser option is exercised(4.1.3).3.4 Whether surface hardening in designated areas isrequired,referencing Supplementary Requirements S10,S11,or S12,and providing the necessary instructions.3.5 For crankshafts designed to include welded counter-weights the purchaser may specify an alternate welding code toAWS D1.1 Structural Welding Code.3.6 For alternate tensile and hardness test requirementsspecify Supplementary Requirement S2.4.Materials and Manufacture4.1 Melting Practice:1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.06 on Steel Forgings and Billets.Current edition approved March 1,2016.Published April 2016.Originallyapproved in 1998.Last previous edition approved in 2011 as A983/A983M 06(2011).DOI:10.1520/A0983_A0983M-06R16.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from American Welding Society(AWS),8669 NW 36 St.,#130,Miami,FL 33166-6672,http:/www.aws.org.4Available from Verlag Stahleisen Gmbh,Postfach 10 51 64,D-40042,Dsseldorf,Germany,http:/www.stahleisen.de.5Available from Japanese StandardsAssociation(JSA),Mita MT Bldg.,3-13-12Mita,Minato-ku,Tokyo 108-0073,Japan,http:/www.jsa.or.jp.*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 4.1.1 The steel making section of Specification A788/A788M shall apply together with mandatory vacuum degas-sing.4.1.2 Supplementary Requirement S1 may be used if non-metallic inclusion rating of the steel is required.4.1.3 Unless otherwise specified by the purchaser(3.2),theforging supplier shall select the chemical composition grade tobe used from Table 2.4.2 Forging:4.2.1 The use of bar from starting stock produced by slittinga rectangular section is not permitted.4.2.2 The procedure used in forging the crankshaft shallensure that the centerline of the starting forged or rolled barwill follow the centerline contour of the main bearings,webs,and crankpins of the crankshaft.4.2.3 The grain flow present between ad