1、Designation: D 6121 08bAn American National StandardStandard Test Method forEvaluation of Load-Carrying Capacity of Lubricants UnderConditions of Low Speed and High Torque Used for FinalHypoid Drive Axles1This standard is issued under the fixed designation D 6121; the number immediately following th
2、e designation indicates the year 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. Scope1.1 This test method is comm
3、only referred to as the L-37test.2This test method covers a test procedure for evaluatingthe load-carrying, wear, and extreme pressure properties of agear lubricant in a hypoid axle under conditions of low-speed,high-torque operation.1.2 This test method also provides for the running of the lowaxle
4、temperature (Canadian) L-37 test. The procedure for thelow axle temperature (Canadian) L-37 test is identical to thestandard L-37 test with the exceptions of the items specificallylisted in Annex A6. The procedure modifications listed inAnnex A6 refer to the corresponding section of the standardL-37
5、 test method.1.3 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 standard.1.3.1 ExceptionsIn Table A9.1, the values stated in SIunits are to be re
6、garded as standard. Also, no SI unit isprovided where there is not a direct SI equivalent.1.4 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 practic
7、es and determine the applica-bility of regulatory limitations prior to use. Specific warninginformation is given in Sections 4 and 7.2. Referenced Documents2.1 ASTM Standards:3D 235 Specification for Mineral Spirits (Petroleum Spirits)(Hydrocarbon Dry Cleaning Solvent)E29 Practice for Using Signific
8、ant Digits in Test Data toDetermine Conformance with Specifications2.2 Military Specification:4MIL-PRF-2105E Lubricating Oil, Gear, Multipurpose2.3 AGMA National Standard:5Nomenclature of Gear Tooth Failure Modes2.4 SAE Standard:6SAE J308 Information Report on Axle and Manual Trans-mission Lubricant
9、sSAE J2360 Lubricating Oil, Gear Multipurpose (Metric)Military Use3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 abrasive wear, non ring and pinion gears, removalof material from the operating surface of the gear caused bylapping of mating surfaces by fine particles suspended
10、 inlubricant, fuel, or air or imbedded in a surface.CRC Rating Manual No. 2173.1.2 adhesive wear, non ring and pinion gears, removalof material from the operating surface of the gear caused byshearing of junctions formed between operating surfaces in1This test method is under the jurisdiction of AST
11、M Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.B0.03 on Automotive Gear Lubricants sheared-off particles either re-main affixed to the harder of the mating surfaces or act as wearparticles between the surfaces. CRC Rating Manual No. 213.1.3 bu
12、rnish, non ring and pinion gears, an alteration ofthe original manufactured surface to a dull or brightly polishedcondition. CRC Rating Manual No. 213.1.4 corrosion, nin final drive axles, a general alterationof the finished surfaces of bearings or gears by discoloration,accompanied by roughening no
13、t attributable to mechanicalaction. CRC Rating Manual No. 213.1.5 deposits, nin final drive axles, material of pasty,gummy, or brittle nature adhering to or collecting around anyof the working parts. CRC Rating Manual No. 213.1.6 discoloration, non ring and pinion gears, any alter-ation in the norma
14、l color of finished steel surfaces.CRC Rating Manual No. 213.1.7 pitting, non ring and pinion gears, small irregularcavities in the tooth surface, resulting from the breaking out ofsmall areas of surface metal. CRC Rating Manual No. 213.1.8 ridging, non ring and pinion gears, an alteration ofthe too
15、th surface to give a series of parallel raised and polishedridges running diagonally in the direction of sliding motion,either partially or completely across the tooth surfaces of gears.CRC Rating Manual No. 213.1.9 rippling, non ring and pinion gears, an alteration ofthe tooth surface to give an ap
16、pearance of a more or lessregular pattern resembling ripples on water or fish scales.CRC Rating Manual No. 213.1.10 scoring, non ring and pinion gears, the rapidremoval of metal from the tooth surfaces caused by the tearingout of small contacting particles that have welded together asa result of met
17、al-to-metal contact. The scored surface ischaracterized by a matte or dull finish.CRC Rating Manual No. 213.1.11 scratching, non ring and pinion gears, an alter-ation of the tooth surface in the form of irregular scratches, ofrandom length, across the tooth surface in the direction ofsliding of the
18、surfaces. CRC Rating Manual No. 213.1.12 spalling, non ring and pinion gears, the breakingout of flakes of irregular area of the tooth surface, a conditionmore extensive than pitting. CRC Rating Manual No. 213.1.13 surface fatigue, non ring and pinion gears, thefailure of the ring gear and pinion ma
19、terial as a result ofrepeated surface or subsurface stresses that are beyond theendurance limit of the material. It is characterized by theremoval of metal and the formation of cavities.AGMA National Standard3.1.14 wear, non ring and pinion gears, the removal ofmetal, without evidence of surface fat
20、igue or adhesive wear,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 contact area (abrasive wear).CRC Rating Manual No. 214. Summary of Test M
21、ethod4.1 Prior to each test run, inspect the test unit (final axleassembly) and measure and record confirming manufacturingspecifications.4.2 Begin the test when the axle assembly is installed on thetest stand and charged with test lubricant.4.3 Gear Conditioning PhaseRun the charged test unit for10
22、0 min at 440 wheel r/min and 395 lbf-ft (535 N-m) torqueper wheel, maintaining an axle sump temperature of 297F(147C). (WarningHigh-speed rotating equipment, electri-cal shock, high-temperature surfaces.)4.4 Gear Test PhaseNext, run the test unit for 24 h at 80wheel r/min, 1740 lbf-ft. (2359 N-m) to
23、rque per wheel and anaxle sump temperature of 275F (135C). (WarningSee4.3.)4.5 The test is completed at the end of the gear test phase.Visually inspect the test parts.4.5.1 Remove the ring gear, pinion, and pinion bearing, andrate for various forms of distress. Use the condition of the ringgear and
24、pinion to evaluate the performance of the test oil.5. Significance and Use5.1 This test method measures a lubricants ability to protectfinal drive axles from abrasive wear, adhesive wear, plasticdeformation, and surface fatigue when subjected to low-speed,high-torque conditions. Lack of protection c
25、an lead to prema-ture gear or bearing failure, or both.5.2 This test method is used, or referred to, in the followingdocuments:5.2.1 American Petroleum Institute (API) Publication1560.85.2.2 STP-512A.95.2.3 SAE J308.5.2.4 Military Specification MIL-PRF-2105E.5.2.5 SAE J2360.6. Apparatus6.1 Test Unit
26、The test unit is a new complete hypoid truckaxle assembly less axle shafts, Dana Model 60, 5.86 to 1ratio.10See Annex A6 for part numbers.6.2 Test Stand and Laboratory Equipment:6.2.1 Axle VentVent the axle to the atmosphere through-out the entire test and arrange the vent so that no water entersthe
27、 housing.6.2.2 Axle CoverThe axle cover has a 3.5-in. (8.9-cm)inspection port installed, as shown in Fig. A2.1. This allowsfilling the axle and provides a means for inspecting the axleafter the gear condition phase (see 10.1). Install a thermo-couple, as described in 6.2.4.1.6.2.3 Test Stand Configu
28、rationMount the complete as-sembly in a rigid fixture as shown in Fig. A3.1. Mount the testunit in the test stand with pinion and axle shaft centerlineshorizontal.8“Lubricant Service Designations for Automotive Manual Transmissions,Manual Transaxles, and Axles,” available from American Petroleum Ins
29、titute, 1220L St. NW, Washington, DC 20005.9“Laboratory Performance Tests for Automotive Gear Lubricants Intended forAPI GL-5 Service.”10The sole source of supply of the apparatus known to the committee at this timeis Dana Corp., P.O. Box 2424, Fort Wayne, IN 46801. If you are aware of alternativesu
30、ppliers, please provide this information to ASTM International Headquarters.Your comments will receive careful consideration at a meeting of the responsibletechnical committee,1which you may attend.D 6121 08b26.2.4 Temperature ControlThe test axle housing shallinclude a means of maintaining the lubr
31、icant at a specifiedtemperature. This shall include a thermocouple, a temperaturerecording system, and a cooling method.6.2.4.1 ThermocoupleDetermine the thermocouple loca-tion on the rear cover using the cover plate temperature sensorlocating device as shown in Fig. A4.1.(1) Install the thermocoupl
32、e such that the thermocoupletip is flush with the cover plate lip by placing the cover plateface on a flat surface and inserting the thermocouple into thecover plate until the thermocouple tip is flush with the flatsurface.(2) Lock the thermocouple into place.6.2.4.2 Temperature Recording SystemThe
33、temperaturerecording system shall record the temperature of the test oilthroughout the test.6.2.4.3 Axle CoolingUse three spray nozzles to distributewater over the cover plate and axle housing as shown in Fig.A5.1. Actuate the water control valve by the temperature PIDcontrol system. See A6.3.2.1 fo
34、r L-37 Canadian Version test.(1) Spray nozzles11shall be any combination of thefollowing part numbers depending on how the system isplumbed: Straight Male NPT (Part No. 3/8GG-SS22), 90Male NPT (Part No. 3/8GGA-SS22), Straight Female NPT(Part No. 3/8G-SS22), and 90 Female NPT (Part No. 3/8GA-SS22).(2
35、) Use a single control valve to control the cooling watersupply. The control shall be a12 in. (12.7 mm) two-way, Clinear trim, air to close, Research Control valve. Use a singlePID loop to maintain the axle lubricant temperature control forboth the Standard and Canadian version test. A separate PIDl
36、oop control for each version is not permitted. See A6.3.2.2 forL-37 Canadian Version test.(3) Use only38 or12 in. (9.5 or 12.7 mm) line material tothe spray nozzles.(4) Use a minimum supply water pressure of 25 psi (172kPa) to the control valve.(5) Use an axle box cover as shown in Fig. A5.2. Thepur
37、pose is to contain water and eliminate drafts.(6) Use a locating pin or stop block as an indexing deviceto ensure that all subsequent axle installations are consistentlyinstalled perpendicular with the axle housing cover to engineand transmission driveshaft centerline.6.2.5 Power SourceThe power sou
38、rce consists of agasoline-powered V-8 engine capable of maintaining testconditions.6.2.6 Dynamometers and Torque Control SystemUse twoaxle dynamometers with sufficient torque absorbing capacity tomaintain axle torque and speed conditions. Suitable controlequipment with sensitivity of adjustment to p
39、ermit mainte-nance of test conditions is required.6.2.7 Dynamometer Connecting ShaftsFabricate shaftsconnecting the dynamometer to the axle shafts. Shafts shall bestrong enough to handle the torques encountered and shall bedynamically (spin) balanced.6.2.8 Drive Shaft and Universal JointsFabricate a
40、 shaftwith universal joints connecting the manual transmission andtest axle. The shaft shall have a 4 6 0.2-in. (10.1 6 0.51-cm)outside diameter with a 0.095 6 0.005 in. (0.24 6 0.013 cm)wall thickness. Shaft and universal joints should be strongenough to handle the torques encountered and shall be
41、dynami-cally (spin) balanced.6.2.9 Transmission and CouplingCouple the engine to thetest unit through a clutch and manual transmission of sufficienttorque carrying capacity to operate normally under test condi-tions.6.3 Speed Measuring and Control System, capable of mea-suring speed of both axles an
42、d also of maintaining testconditions.7. Reagents and Materials7.1 Sealing Compound, where necessary, Permatex No. 2,or equivalent.7.2 SolventUse only mineral spirits meeting the require-ments of Specification D 235, Type II, Class C for AromaticContent (0-2% vol), Flash Point (142F/61C, min) and Col
43、or(not darker than +25 on Saybolt Scale or 25 on Pt-Co Scale).(WarningCombustible. Health hazard.) Obtain a Certificateof Analysis for each batch of solvent from the supplier.8. Preparation of Apparatus8.1 Cleaning of Reusable HardwareClean as necessaryall reusable parts including axle shafts, therm
44、ocouples axlehousing cover, and all associated drain pans and funnels usedfor the addition of and collection of test oil.8.2 Preparation of Axle:8.2.1 Record the “as received” drive side contact patternlength and flank values as noted on the axle housing from DanaCorp.10Length values of L2and L3and
45、flank values of F1,F0,and F+1are considered acceptable. Any adjustments that aremade to the axle prior to testing shall be noted in the commentssection of the test report.Axle housings from prior gear batchesthat do not have contact pattern markings shall be patternedand reported by the test labs in
46、 the test report.8.2.2 Break and Turn Torque MeasurementsDetermineand record the torques required to break and to turn the pinionshaft of the completely assembled test unit.8.2.3 Backlash MeasurementsRecord the backlash on thetest axle reported from the manufacturer. To be acceptable, thebacklash re
47、ported by the manufacturer shall be between 0.004to 0.012 in. (0.102 to 0.305 mm).8.2.3.1 If the test axle does not have a reported backlashfrom the manufacturer, the average backlash, as measured in8.2.3.2, shall be between 0.004 and 0.009 in. (0. 102 to 0.229mm).8.2.3.2 Remove the cover plate. Mea
48、sure and record back-lash at four equally spaced locations. Report the average andthe four readings.11The sole source of supply of the apparatus known to the committee at this timeis Spray Systems Company, and the spray nozzles can be purchased through E.I.Pfaff Company, 3443 Edwards Road, Suite D,
49、Cincinnati, OH 45208. If you areaware of alternative suppliers, please provide this information to ASTM Interna-tional Headquarters. Your comments will receive careful consideration at a meetingof the responsible technical committee,1which you may attend.D 6121 08b38.2.4 CleaningWash the test unit using a cleaning solvent(see 7.2), paying particular attention to the pinion bearings toremove all preservative oil. Dry by blowing with clean, drycompressed air.8.2.5 Lubricate the carrier bearings, pinion bearings, differ-ential gears, and t
