1、Designation: D 7450 08An American National StandardStandard Specification forPerformance of Rear Axle Gear Lubricants Intended for APICategory GL-5 Service1This standard is issued under the fixed designation D 7450; the number immediately following the designation indicates the year oforiginal adopt
2、ion 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. Scope1.1 This specification covers test methods and acceptancecriteria for determi
3、ning the acceptability of gear oils forapplications which specify a lubricant meeting the performancerequirements of API Category GL-5 service. Lubricants whichmeet these performance requirements are typically intended foruse in automotive axles, particularly those containing hypoidgears, operating
4、under various combinations of high-speed/shock-load and low-speed/high-torque conditions.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered stand
5、ard.1.3 This standard 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.2. Referenc
6、ed Documents2.1 ASTM Standards:2D 130 Test Method for Corrosiveness to Copper fromPetroleum Products by Copper Strip TestD 892 Test Method for Foaming Characteristics of Lubri-cating OilsD 5704 Test Method for Evaluation of the Thermal andOxidative Stability of Lubricating Oils Used for ManualTransm
7、issions and Final Drive AxlesD 6121 Test Method for Evaluation of Load-Carrying Ca-pacity of Lubricants Under Conditions of Low Speed andHigh Torque Used for Final Hypoid Drive AxlesD 7038 Test Method for Evaluation of Moisture CorrosionResistance of Automotive Gear Lubricants2.2 Military Standards:
8、3MIL-L-2105C Lubricating Oil, Gear, MultipurposeMIL-L-2105D Lubricating Oil, Gear, MultipurposeMIL-PRF-2105E Lubricating Oil, Gear, Multipurpose2.3 ASTM Test Monitoring Center Documents:4L-42 Test Procedure2.4 SAE Documents:5J306 Automotive Gear Lubricant Viscosity ClassificationJ2360 Lubricating Oi
9、l, Gear Multipurpose (Metric) MilitaryUse3. Terminology3.1 Definitions:3.1.1 ridging, non ring and pinion gears, an alteration ofthe tooth surface to give a series of parallel raised and polishedridges running diagonally in the direction of sliding motion,either partially or completely across the to
10、oth surfaces of gears.D 61213.1.2 rippling, non ring and pinion gears, an alteration ofthe tooth surface to give an appearance of a more or lessregular pattern resembling ripples on water or fish scales.D 61213.1.3 pitting, non ring and pinion gears, small irregularcavities in the tooth surface, res
11、ulting from the breaking out ofsmall areas of surface metal. D 61213.1.4 spalling, non ring and pinion gears, the breakingout of flakes of irregular area of the tooth surface, a conditionmore extensive than pitting. D 61213.1.5 scoring, non ring and pinion gears, the rapidremoval of metal from the t
12、ooth surfaces caused by the tearingout of small contacting particles that have welded together asa result of metal-to-metal contact. The scored surface ischaracterized by a matte or dull finish. D 61213.1.6 wear, non ring and pinion gears, the removal ofmetal, without evidence of surface fatigue or
13、adhesive wear,1This specification is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.B0 on Automotive Lubricants.Current edition approved May 1, 2008. Published June 2008.2For referenced ASTM standards, visit the AS
14、TM 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 Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philad
15、elphia, PA 19111-5098, http:/www.dodssp.daps.mil.4Available from ASTM Test Monitoring Center, 6555 Penn Avenue, Pittsburgh,PA 152064489, Attn: Administrator.5Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001, http:/www.sae.org.1Copyright ASTM Intern
16、ational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.resulting in partial or complete elimination of tool or grindingmarks or development of a discernible shoulder ridge at thebottom of the contact area near the root or at the toe or heel endof pinion tooth co
17、ntact area (abrasive wear). D 61213.2 Definitions of Terms Specific to This Standard:3.2.1 lubrited, adjhaving its surface coated with phos-phate.4. Performance Classification4.1 API Category GL-5The designation API CategoryGL-5 is designed to identify the category of lubricants intendedfor gears, p
18、articularly those in automotive axles equipped withhypoid gears, operating under various combination of high-speed/shock-load and low-speed/high-torque conditions. Ap-proved lubricants under the SAE J2360 Standard, the MIL-L-2105C Specification, the MIL-L-2105D Specification, and theMIL-PRF-2105E Sp
19、ecification satisfy the requirements of APICategory GL-5. Note that these standards and specificationscontain performance requirements that exceed those of APICategory GL-5.5. Performance Requirements5.1 API Category GL-5 performance requirements for can-didate gear lubricants using the most current
20、 test methods andprocedures are provided in Table 1.6. Keywords6.1 axle lubricants; gear lubricants; high-speed/shock-load;hypoid gear lubricants; hypoid gears; low-speed/high-torqueTABLE 1 API Category GL-5 Tests and Acceptance CriteriaTest Item Minimum MaximumL-42A,B. Equal to or better (lower) th
21、an the meanscoring value of the passing reference oiltest results used to calibrate the stand%Scoring, PinionDrive SideCoast Side%Scoring, RingDrive SideCoast SideTest Method D 6121 (formerly L-37) using non-lubrited hardwareB,CRidging, ASTM merit rating 8 .Rippling, ASTM merit rating 8 .Wear, ASTM
22、merit rating 5 .Pitting/Spalling, ASTM merit rating 9.3 .Scoring, ASTM merit rating 10 .Test Method D 7038 (formerly L-33-1)DFinal rust merit rating 9.0Test Method D 5704E(formerly L-60-1) or L-60Viscosity Increase, percent 100Pentane Insolubles, wt percent 3.0Toluene Insolubles, wt percent 2.0Test
23、Method D 892, tendencySequence I, mL . 20Sequence II, mL . 50Sequence III, mL . 20Test Method D 130FASTM rating . 3AThe latest version of this test can be obtained from the ASTM Test Monitoring Center. The Canadian version of the L-42 test follows the procedure of the L-42 testwith the modifications
24、 detailed in Annex A1, Table A1.1 of the L-42 test procedure.BThis test may be conducted under two different sets of operating conditions, commonly referred to as Standard and Canadian. The test conditions to be used aredependant upon the viscosity grade of the lubricant under evaluation. Please see
25、 A2.2 and Table A2.1 for details as to which version of this test should be used in theevaluation of a specific lubricant.CThe Canadian version of the Test Method D 6121 test follows the procedure of the Test Method D 6121 test with the modifications detailed in Test Method D 6121,Annex A6.2, Table
26、A6.1.DCandidate fluids tested previous to the development of the Test Method D 7038 procedure using the L-33 test procedure with a cover plate merit rating of a minimumof 8 and a merit rating for all other areas of a minimum of 10 are considered acceptable results against the performance requirement
27、s of this Specification.ECarbon or Varnish and Sludge ratings are reported in Test Method D 5704 but are not an acceptance criterion for API Category GL-5.FTested for 3 h at 250F (121C).D7450082ANNEXES(Mandatory Information)A1. USE OF CALIBRATED TEST STANDS FOR API CATEGORY GL-5 PERFORMANCE EVALUATI
28、ONA1.1 The latest versions of the Test Methods D 5704,D 6121, D 7038, and the L-42 test procedure require test standcalibration by the ASTM TMC. The use of calibrated teststands is required for evaluation of a lubricant against theperformance requirements of this specification.A2. AUTOMOTIVE GEAR LU
29、BRICANT VISCOSITYA2.1 The SAE J306 Standard describes the system ofviscosity classifications used for automotive gear lubricants.A2.2 The Test Method D 6121 and L-42 tests proceduremay be conducted under two different sets of operatingconditions commonly referred to as Standard and Canadian.The test
30、 conditions to be used are dependent upon the viscositygrade of the lubricant under evaluation. Table A2.1 lists theAPI Category GL-5 testing requirements for candidate gearlubricants, according to their viscosity grade.APPENDIXES(Nonmandatory Information)X1. API CATEGORY GL-5 SPECIFICATION RATIONAL
31、EX1.1 API Category GL-5 is routinely referenced around theworld. There has not been, however, an ASTM Standard thatdefined the performance requirements of gear oils intended forAPI Category GL-5 service. This absence of a readily availableASTM standard may have resulted in confusion in the market-pl
32、ace, and made it difficult to communicate updates or changesin test procedures and pass or fail criteria used to evaluate theperformance of lubricants against the performance require-ments of API Category GL-5. To address this issue, ASTMD02.B0.03 created a task force whose purpose was to docu-ment
33、the test methods and procedures and performance re-quirements of API Category GL-5 as an ASTM standard.TABLE A2.1 API Category GL-5 Testing Requirements According to the Viscosity Grade of the Candidate Gear LubricantTest Item SAE 70Wor through the ASTM website(www.astm.org).6STP 512A, Laboratory Performance Tests for Automotive Gear LubriantsIntended for API GL-5 Service, ASTM International, W. Conshohocken, PA, 1986.D7450084
