1、Designation:A290/A290M16Standard Specification forCarbon and Alloy Steel Forgings for Rings for ReductionGears1This standard is issued under the fixed designation A290/A290M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of
2、 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 normalized and tempered,andquenched and tempered,carbon and alloy steel forged or rolledrings
3、for reduction gears.1.2 Several grades and classes of steel are covered asfollows:1.2.1 Grade 1,Classes A and B,and Grade 2,Classes C andD,are carbon steel.1.2.2 Grade 3,Classes E and F,Grade 4,Classes G,H,I,J,K and L,Grade 5,Classes M and P,and Grade 6,Class T,arealloy steel.1.2.3 All grades and cl
4、asses are considered weldable underproper conditions.Welding techniques are of fundamentalimportance and it is pre-supposed that welding procedure andinspection will be in accordance with proper methods for theclass of material used.1.3 The values stated in either SI units or inch-pound unitsare to
5、be regarded separately as standard.The 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.1.4 This standard does not purport to address all of thesa
6、fety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2A275/A275M Practice for Magnetic P
7、article Examination ofSteel ForgingsA370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA388/A388M Practice for Ultrasonic Examination of SteelForgingsA788/A788M Specification for Steel Forgings,General Re-quirements3.Terminology3.1 Definitions of the terms used may be found in
8、Specifi-cation A788/A788M.4.Ordering Information and General Requirements4.1 In addition to the ordering information required bySpecification A788/A788M,the purchaser shall specify in theinquiry,contract,and order the grade and class desired and thesupplementary requirements,if any,which should appl
9、y.4.2 Material supplied to this specification shall conform tothe requirements of Specification A788/A788M,which out-linesadditionalorderinginformation,manufacturingrequirements,testing and retesting methods and procedures,marking,certification,product analysis variations,and addi-tional supplementa
10、ry requirements.5.Materials and Manufacture5.1 Melting Process:5.1.1 The steel shall be produced by any of the meltingrequirements in Specification A788/A788M,which may besupplemented by Supplementary Requirement S6,VacuumDegassing.5.2 DiscardSufficient discard shall be taken from eachingot to secur
11、e freedom from piping and undue segregation.5.3 Forging ProcessThe forgings shall receive their hotmechanical work in accordance with the requirements ofSpecification A788/A788M.5.4 Heat Treatment:5.4.1 Cooling Prior to Heat TreatmentAfter forging andbefore reheating for heat treatment,the forgings
12、shall beallowed to cool in a manner to prevent injury,to accomplishtransformation,and prevent flakes.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.Cu
13、rrent edition approved May 1,2016.Published May 2016.Originallyapproved in 1946.Last previous edition approved in 2015 as A290/A290M 05(2015).DOI:10.1520/A0290_A0290M-16.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual B
14、ook 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 5.4.2 Heat treatment
15、shall consist of normalizing and tem-pering for Grade 1 classes A and B and quenching andtempering for all other grades and classes.5.4.2.1 NormalizingA furnace charge thus treated istermed a normalizing charge.5.4.2.2 QuenchingThe forgings shall be completely aus-tenitized and then quenched in a su
16、itable medium.Agroup thustreated is termed a quenching charge.5.4.2.3 TemperingA furnace charge thus treated is termeda tempering charge.Minimum tempering temperatures shall beas follows:Minimum Tempering TemperatureGrade and ClassFCGrade 1 Classes A and B1200650Grade 2 Classes C&D,E,F,G,H,M,P1100595Grade 3 Classes E&F1100595Grade 4 Classes G&H1100595Grade 5 Classes M&P1100595Grade 4 Classes I,J,K&L1050565Grade 6 Class T10005405.5 Machining:5.5.1 Rough machining before heat treatment for mechani
