1、Designation:A456/A456M08(Reapproved 2013)Standard Specification forMagnetic Particle Examination of Large CrankshaftForgings1This standard is issued under the fixed designation A456/A456M;the number immediately following the designation indicates the yearof original adoption or,in the case of revisi
2、on,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.Scope1.1 This is an acceptance specification for the magneticparticle inspection of forged steel crankshafts having
3、mainbearing journals or crankpins 4 in.200 mm or larger indiameter.1.2 There are three classes,with acceptance standards ofincreasing severity:1.2.1 Class 1.1.2.2 Class 2(originally the sole acceptance standard of thisspecification).1.2.3 Class 3(formerly covered in Supplementary Require-ment S1 of
4、Specification A456 64(1970).1.3 This specification is not intended to cover continuousgrain flow crankshafts(see Specification A983/A983M);however,Specification A986/A986M may be used for thispurpose.NOTE1Specification A668/A668M is a product specification whichmay be used for slab-forged crankshaft
5、 forgings that are usually twisted inorder to set the crankpin angles,or for barrel forged crankshafts where thecrankpins are machined in the appropriate configuration from a cylindricalforging.1.4 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The
6、values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.1.5 Unless the order specifies the applicable“M”specifica-tion designation,the material shall be
7、furnished to the inchunits.2.Referenced Documents2.1 ASTM Standards:2A275/A275M Practice for Magnetic Particle Examination ofSteel ForgingsA668/A668M Specification for Steel Forgings,Carbon andAlloy,for General Industrial UseA966/A966M Practice for Magnetic Particle Examination ofSteel Forgings Usin
8、g Alternating CurrentA983/A983M Specification for Continuous Grain FlowForged Carbon and Alloy Steel Crankshafts for MediumSpeed Diesel EnginesA986/A986M Specification for Magnetic Particle Examina-tion of Continuous Grain Flow Crankshaft ForgingsE1417/E1417M Practice for Liquid Penetrant Testing3.C
9、lassification of Indications3.1 Magnetic particle indications on the surface of thecrankshaft shall be classified as follows:3.1.1 Open cracks,flake,or pipe.3.1.2 Nonmetallic inclusions or stringers occurring in alongitudinal direction.3.1.3 Twist cracks or nonmetallic inclusions usually occur-ring
10、at 45 to 70 from the axis of the journal.3.2 They shall also be classified as follows:3.2.1 Open indications are visible after removal of themagnetic particles or can be detected by the use of contrast dyepenetrant,as described in Type II of Practice E1417/E1417M.3.2.1.1 Pinpoint indications are ope
11、n indications116in.1.5mm in maximum dimension,as detected by application ofType II of Practice E1417/E1417M.3.2.2 Non-open indications are indications which are notvisually detectable as described in 3.2.1.1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel a
12、nd Related Alloys,and is the direct responsibility of SubcommitteeA01.06 on Steel Forgings and Billets.Current edition approved April 1,2013.Published April 2013.Originallyapproved in 1999.Last previous edition approved in 2008 as A456/A456M 08.DOI:10.1520/A0456_A0456M-08R13.2For referenced ASTM sta
13、ndards,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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-
14、2959.United States1 4.Ordering Information4.1 The inquiry and purchase agreement shall contain astatement that the crankshaft(s)is(are)to be subject toacceptance according to this specification.If reference to classis omitted,Class 2 shall apply.4.2 The use of Supplementary Requirements S1 and S2sho
15、uld be specified if required.5.Procedure5.1 Magnetic particle inspection shall be conducted accord-ing to Practice A966/A966M,except when SupplementaryRequirement S1 is to be used.The use of prod type contacts isnot permitted on finished crankshafts.Magnetic leeches mayonly be used on noncritical pa
16、rts of the crankshaft whenSupplementary Requirement S2 is utilized.6.Areas of Inspection6.1 Major Critical Areas:6.1.1 The critical area of any crankpin shall be that area plusor minus 60 from the 6 oclock position of the pin extending38in.10 mm above the thrust collar around the fillet,and58in.16 mm into the pin along its axis measured fromapproximately the blend of the pin surface and fillet,as shownin Fig.1 and Fig.2.6.1.2 The critical areas of any main bearing journal shall bethat area plus
