1、Designation:D745215Standard Test Method forEvaluation of the Load Carrying Properties of LubricantsUsed for Final Drive Axles,Under Conditions of High Speedand Shock Loading1This standard is issued under the fixed designation D7452;the number immediately following the designation indicates the year
2、oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers the determination of the anti-scoring p
3、roperties of final drive axle lubricating oils whensubjected to high-speed and shock conditions.This test methodis commonly referred to as the L-42 test.21.2 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units th
4、at are provided for information onlyand are not considered standard.1.2.1 ExceptionsSI units are provided for all parametersexcept where there is no direct equivalent such as the units forscrew threads,National Pipe Threads/diameters,tubing size,and single source equipment suppliers.1.3 This standar
5、d does not purport to address all of thesafety 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.Specific warninginformation is giv
6、en in Sections 4 and 7.2.Referenced Documents2.1 ASTM Standards:3D235 Specification for Mineral Spirits(Petroleum Spirits)(Hydrocarbon Dry Cleaning Solvent)E29 Practice for Using Significant Digits in Test Data toDetermine Conformance with Specifications2.2 Society of Automotive Engineers Standards:
7、4SAE J308 Information Report on Axle and Manual Trans-mission LubricantsSAE J2360 Lubricating Oil,Gear Multipurpose(Metric)Military Use3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 coast side,nthe convex side of the pinion and theconcave side of the ring gear which are in con
8、tact duringdeceleration in a forward gear.ASTM Distress Rating Manual 2153.1.2 drive side,nthe concave side of the pinion and theconvex side of the ring gear which are in contact duringacceleration in a forward gear.ASTM Distress Rating Manual 213.1.3 scoring,non the ring and the pinion gear teeth,t
9、hedisplacement of metal by local momentary welding from thegear tooth,resulting in the development of a matt,or frosteddull surface.ASTM Distress Rating Manual 214.Summary of Test Method4.1 Charge a specially prepared light duty hypoid rear axle(Dana Model 44 ASTM Part No.044AA100-1)6with thelubrica
10、nt sample to be tested(see 10.1).Mount the axlebetween two load absorbing dynamometers which are drivenwith a V-8 gasoline engine through a manual transmission.4.2 Condition the test axle with light loads at differentspeed,torque and temperature conditions on both the drive andcoast sides of the gea
11、rs.(WarningHigh-speed rotatingequipment,electrical shock,high-temperature surfaces.)Afterconditioning,subject the test axle to high speed and shockloadings at higher temperatures.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is
12、 the direct responsibility ofSubcommittee D02.B0.03 on Automotive Gear Lubricants&Fluids.Current edition approved Oct.1,2015.Published November 2015.Originallyapproved in 2008.Last previous edition approved in 2014 as D7452 14.DOI:10.1520/D7452-15.2Until the next revision of this test method,the AST
13、M Test Monitoring Center(TMC)will update changes in this test method by means of information letters.Information letters may be obtained from the ASTM Test Monitoring Center,6555Penn Avenue,Pittsburgh,PA 15206,Attention:Administrator.This edition incor-porates revisions in all information Letters th
14、rough No.151.The TMC is also asource of reference oils.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.4Available
15、from Society of Automotive Engineers(SAE),400 CommonwealthDr.,Warrendale,PA 15096-0001,http:/www.sae.org.5Formerly known as CRC Rating Manual,No.21.Available from the ASTMwebsite,www.astm.org,ASTM Stock No.TMCMNL21.6Parts and Model 44 Maintenance Manual available from Dana Corporation,P.O.Box 2424,F
16、ort Wayne,IN 46801.*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 4.3 Rate the drive and coast side of the pinion and ring gearsat the end of test(EOT)for scoring distress.5.Significance and Use5.1 Final drive axles are often subjected to severe servicewhere they encounter high speed shock torque conditions,characterized by sudden accelerations and decelerations.Thissev
