1、Designation: D6121 13D6121 14Standard 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 D6121; the number immediately following the designation indicates
2、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. Scope*1.1 This test method is commonly referred to as the
3、 L-37 test.2 This test method covers a test procedure for evaluating theload-carrying, wear, and extreme pressure properties of a gear 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 low axle temperature (Canadi
4、an) L-37 test. The procedure for the lowaxle temperature (Canadian) L-37 test is identical to the standard L-37 test with the exceptions of the items specifically listed inAnnex A6. The procedure modifications listed in Annex A6 refer to the corresponding section of the standard L-37 test method.1.3
5、 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information only and are not considered standard.1.3.1 ExceptionsIn TableA9.1, the values stated in SI units are to be regarded as stan
6、dard.Also, no SI unit is provided wherethere is not a direct SI equivalent.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determin
7、e the applicability of regulatorylimitations prior to use. Specific warning information is given 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 Te
8、st Data to Determine 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 Transmission LubricantsSAE J2360 Lubri
9、cating Oil, Gear Multipurpose (Metric) Military Use3. Terminology3.1 Definitions of Terms Specific to This Standard:1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.B0.03 on Autom
10、otive Gear Lubricants sheared-off particles either remain affixed to theharder of the mating surfaces or act as wear particles between the surfaces.ASTM Distress Rating Manual No. 213.1.3 broken gear tooth, na gear tooth where a portion of the tooth face is missing and the missing material includes
11、somepart of the top land, toe, heel, or coast side of the tooth.3.1.3.1 DiscussionThis condition is distinct from and more extensive than “chipping,” which is defined in 3.1.5.3.1.4 burnish, non ring and pinion gears, an alteration of the original manufactured surface to a dull or brightly polishedc
12、ondition. ASTM Distress Rating Manual No. 213.1.5 chipping, non ring and pinion gears, a condition caused in the manufacturing process in which a small irregular cavityis present only at the face/crown edge interface. The edge-chipping phenomenon occurs when sufficient fatigue cycles accumulateafter
13、 tooth surface wear relieves the compressive residual stress on the tooth profile side of the profile-to-topland interface.Chipping within 1 mm of the face/crown edge interface is to be called chipping, not pitting/spalling. ASTM Distress RatingManual No. 213.1.6 corrosion, nin final drive axles, a
14、general alteration of the finished surfaces of bearings or gears by discoloration,accompanied by roughening not attributable to mechanical action. ASTM Distress Rating Manual No. 213.1.7 deposits, nin final drive axles, material of pasty, gummy, or brittle nature adhering to or collecting around any
15、 of theworking parts.ASTM Distress Rating Manual No. 213.1.8 discoloration, non ring and pinion gears, any alteration in the normal color of finished steel surfaces.ASTM Distress Rating Manual No. 213.1.9 pitting, non ring and pinion gears, small irregular cavities in the tooth surface, resulting fr
16、om the breaking out of smallareas of surface metal.ASTM Distress Rating Manual No. 213.1.10 ridging, non ring and pinion gears, an alteration of the tooth surface to give a series of parallel raised and polishedridges running diagonally in the direction of sliding motion, either partially or complet
17、ely across the tooth surfaces of gears.ASTM Distress Rating Manual No. 213.1.11 rippling, non ring and pinion gears, an alteration of the tooth surface to give an appearance of a more or less regularpattern resembling ripples on water or fish scales.ASTM Distress Rating Manual No. 213.1.12 scoring,
18、non ring and pinion gears, the rapid removal of metal from the tooth surfaces caused by the tearing out ofsmall contacting particles that have welded together as a result of metal-to-metal contact. The scored surface is characterized bya matte or dull finish.ASTM Distress Rating Manual No. 213.1.13
19、scratching, non ring and pinion gears, an alteration of the tooth surface in the form of irregular scratches, of randomlength, across the tooth surface in the direction of sliding of the surfaces.ASTM Distress Rating Manual No. 213.1.14 spalling, non ring and pinion gears, the breaking out of flakes
20、 of irregular area of the tooth surface, a condition moreextensive than pitting.ASTM Distress Rating Manual No. 213.1.15 surface fatigue, non ring and pinion gears, the failure of the ring gear and pinion material as a result of repeatedsurface or subsurface stresses that are beyond the endurance li
21、mit of the material. It is characterized by the removal of metal andthe formation of cavities.AGMA National Standard3.1.16 wear, non ring and pinion gears, the removal of metal, without evidence of surface fatigue or adhesive wear, resultingin partial or complete elimination of tool or grinding mark
22、s or development of a discernible shoulder ridge at the bottom of the7 Formerly known as CRC Manual 21. Available from the ASTM website, www.astm.org, (TMCMNL21).D6121 142contact area near the root or at the toe or heel end of pinion tooth contact area (abrasive wear).ASTM Distress Rating Manual No.
23、 214. Summary of Test Method4.1 Prior to each test run, inspect the test unit (final axle assembly) and measure and record confirming manufacturingspecifications.4.2 Begin the test when the axle assembly is installed on the test stand and charged with test lubricant.4.3 Gear Conditioning PhaseRun th
24、e charged test unit for 100 min at 440 wheel r/min and 395 lbf-ft (535 Nm) torque perwheel, maintaining an axle sump temperature of 297F (147 C). (WarningHigh-speed rotating equipment, electrical shock,high-temperature surfaces.)4.4 Gear Test PhaseNext, run the test unit for 24 h at the operating co
25、nditions dictated by the hardware batch and typecombination (see 10.2.3.1).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, and rate for various forms of distress. Use the condition of the ring gearan
26、d pinion to evaluate the performance of the test oil.5. Significance and Use5.1 This test method measures a lubricants ability to protect final drive axles from abrasive wear, adhesive wear, plasticdeformation, and surface fatigue when subjected to low-speed, high-torque conditions. Lack of protecti
27、on can lead to prematuregear or bearing failure, or both.5.2 This test method is used, or referred to, in the following documents:5.2.1 American Petroleum Institute (API) Publication 1560.85.2.2 STP-512A.95.2.3 SAE J308.5.2.4 Military Specification MIL-PRF-2105E.5.2.5 SAE J2360.6. Apparatus6.1 Test
28、UnitThe test unit is a new complete hypoid truck axle assembly less axle shafts, Dana Model 60, 5.86 to 1 ratio.10See Annex A6 for part numbers.6.2 Test Stand and Laboratory Equipment:6.2.1 Axle VentVent the axle to the atmosphere throughout the entire test and arrange the vent so that no water ente
29、rs thehousing.6.2.2 Axle CoverThe axle cover may have a port installed to allow for ring gear inspection after the gear condition phase (see10.1). See Fig. A2.1 for an example.6.2.3 Test Stand ConfigurationMount the complete assembly in a rigid fixture as shown in Fig. A3.1. Mount the test unit inth
30、e test stand with pinion and axle shaft centerlines horizontal.6.2.4 Temperature ControlThe test axle housing shall include a means of maintaining the lubricant at a specified temperature.This shall include a thermocouple, a temperature recording system, and a cooling method.6.2.4.1 ThermocoupleDete
31、rmine the thermocouple location on the rear cover using the cover plate temperature sensorlocating device as shown in Fig. A4.1.(1) Install the thermocouple such that the thermocouple tip is flush with the cover plate lip by placing the cover plate faceon a flat surface and inserting the thermocoupl
32、e into the cover plate until the thermocouple tip is flush with the flat surface.(2) Lock the thermocouple into place.6.2.4.2 Temperature Recording SystemThe temperature recording system shall record the temperature of the test oilthroughout the test.6.2.4.3 Axle CoolingUse three spray nozzles to di
33、stribute water over the cover plate and axle housing as shown in Fig. A5.1.Actuate the water control valve by the temperature PID control system. See A6.3.2.1 for L-37 Canadian Version test.8 “Lubricant Service Designations for Automotive Manual Transmissions, Manual Transaxles, and Axles,” availabl
34、e from American Petroleum Institute, 1220 L St. NW,Washington, DC 20005.9 “Laboratory Performance Tests for Automotive Gear Lubricants Intended for API GL-5 Service.”10 The sole source of supply of the apparatus known to the committee at this time is Dana Corp., P.O. Box 2424, Fort Wayne, IN 46801.
35、If you are aware of alternativesuppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsible technicalcommittee,1 which you may attend.D6121 143(1) Spray nozzles11 shall be any combination of the follow
36、ing part numbers depending on how the system is plumbed: StraightMale NPT (Part No. 3/8GG-SS22), 90 Male NPT (Part No. 3/8GGA-SS22), Straight Female NPT (Part No. 3/8G-SS22), and 90Female NPT (Part No. 3/8GA-SS22).(2) Use a single control valve to control the cooling water supply. The control shall
37、be a 12 in. (12.7 mm) two-way, C lineartrim, air to close, Research Control valve. Use a single PID loop to maintain the axle lubricant temperature control for both theStandard and Canadian version test.Aseparate PID loop control for each version is not permitted. See A6.3.2.2 for L-37 CanadianVersi
38、on test.(3) Use only 38 or 12 in. (9.5 mm or 12.7 mm) line material to the spray nozzles.(4) Use a minimum supply water pressure of 25 psi (172 kPa) to the control valve.(5) Use an axle box cover as shown in Fig. A5.2. The purpose is to contain water and eliminate drafts.(6) Use a locating pin or st
39、op block as an indexing device to ensure that all subsequent axle installations are consistentlyinstalled perpendicular with the axle housing cover to engine and transmission driveshaft centerline.6.2.5 Power SourceThe power source consists of a gasoline-powered V-8 engine capable of maintaining tes
40、t conditions.6.2.6 Dynamometers and Torque Control SystemUse two axle dynamometers with sufficient torque absorbing capacity tomaintain axle torque and speed conditions. Suitable control equipment with sensitivity of adjustment to permit maintenance of testconditions is required.6.2.7 Dynamometer Co
41、nnecting ShaftsFabricate shafts connecting the dynamometer to the axle shafts. Shafts shall be strongenough to handle the torques encountered and shall be dynamically (spin) balanced.6.2.8 Drive Shaft and Universal JointsFabricate a shaft with universal joints connecting the manual transmission and
42、test axle.The shaft shall have a 4 6 0.2-in. (10.1 cm 6 0.51 cm) outside diameter with a 0.095 6 0.005 in. (0.24 cm 6 0.013 cm) wallthickness. Shaft and universal joints should be strong enough to handle the torques encountered and shall be dynamically (spin)balanced.6.2.9 Transmission and CouplingC
43、ouple the engine to the test unit through a clutch and manual transmission of sufficienttorque carrying capacity to operate normally under test conditions.6.3 Speed Measuring and Control System, capable of measuring speed of both axles and also of maintaining test conditions.7. Reagents and Material
44、s7.1 Sealing Compound, where necessary, Permatex No. 2, or equivalent.7.2 SolventUse only mineral spirits meeting the requirements of Specification D235, Type II, Class C for Aromatic Content(0-2% vol), Flash Point (142F/61C, min) and Color (not darker than +25 on Saybolt Scale or 25 on Pt-Co Scale)
45、.(WarningCombustible. Health hazard.) Obtain a Certificate of Analysis for each batch of solvent from the supplier.8. Preparation of Apparatus8.1 Cleaning of Reusable HardwareClean as necessary all reusable parts including axle shafts, thermocouples axle housingcover, and all associated drain pans a
46、nd funnels used for the addition of and collection of test oil.11 The sole source of supply of the apparatus known to the committee at this time is Spray Systems Company, and the spray nozzles can be purchased through E.I. PfaffCompany, 3443 Edwards Road, Suite D, Cincinnati, OH 45208. If you are aw
47、are of alternative suppliers, please provide this information toASTM International Headquarters.Your comments will receive careful consideration at a meeting of the responsible technical committee,1 which you may attend.D6121 1448.2 Preparation of Axle:8.2.1 Record the “as received” drive side conta
48、ct pattern length and flank values as noted on the axle housing from Dana Corp.10Length values of L2 and L3 and flank values of F1, F0, and F+1 are considered acceptable. Note any adjustments that are madeto the axle prior to testing in the comments section of the test report. Test labs pattern and
49、report, in the test report, axle housingsfrom prior gear batches that do not have contact pattern markings.8.2.2 Break and Turn Torque MeasurementsDetermine and record the torques required to break and to turn the pinion shaftof the completely assembled test unit.8.2.3 Backlash MeasurementsRecord the backlash on the test axle reported from the manufacturer. To be acceptable, thebacklash reported by the manufacturer shall be between 0.004 to 0.012 in. (0.102 mm to 0.305 mm).8.2.3.1 If the test axle does not have a reported backlash fro
