1、Designation: D6121 16aD6121 17Standard 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.INTRODUCTIONThis test method is written for use by laborato
3、ries that use the portions of the test method that referto ASTM Test Monitoring Center (TMC) services (see Annex A1 Annex A4). Laboratories thatchoose not to use the TMC services may simply disregard these portions.The TMC provides reference oils, and engineering and statistical services to laborato
4、ries that desireto produce test results that are statistically similar to those produced by laboratories previouslycalibrated by the TMC.In general, the Test Purchaser decides if a calibrated test stand is to be used. Organizations such astheAmerican Chemistry Council require that a laboratory utili
5、ze the TMC services as part of their testregistration process. In addition, the American Petroleum Institute and the Gear Lubricant ReviewCommittee of the Lubricant Review Institute (SAE International) require that a laboratory use theTMC services in seeking qualification of oils against their speci
6、fications.NOTE 1The advantage of using the TMC services to calibrate test stands is that the test laboratory (and hence theTest Purchaser) has an assurance that the test stand was operating at the proper level of test severity. It should also beborne in mind that results obtained in a non calibrated
7、 test stand may not be the same as those obtained in a test standparticipating in the ASTM TMC services process.1. Scope*1.1 This test method is commonly referred to as the L-37 test.2 This test method covers a test procedure for evaluating theload-carrying, wear, and extreme pressure properties of
8、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 (Canadian) L-37 test. The procedure for the lowaxle temperature (Canadian) L-37 test is identical to the standard L-37 test with the ex
9、ceptions of the items specifically listed inAnnex A9. The procedure modifications listed in Annex A9 refer to the corresponding section of the standard L-37 test method.1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematicalconversio
10、ns to SI units that are provided for information only and are not considered standard.1.3.1 ExceptionsIn TableA12.1, the values stated in SI units are to be regarded as standard.Also, no SI unit is provided wherethere is not a direct SI equivalent.1.4 This standard does not purport to address all of
11、 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 determine the applicability of regulatorylimitations prior to use. Specific warning information is given in Sections 4 and 7.1.5 This i
12、nternational standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT)
13、Committee.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 Automotive Gear Lubricants sheared-off particles either remain affixed to theharder of the mating surfaces or a
14、ct 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 somepart of the top land, toe, heel, or coast side of the tooth.3.1.3.1 DiscussionThis condition is distin
15、ct 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 polishedcondition. ASTM Distress Rating Manual No. 213.1.5 chipping, non ring and pinion gears, a condition caused
16、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 tooth surface wear relieves the compressive residual stress on the tooth profile side of the profile-to-t
17、opland 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 general alteration of the finished surfaces of bearings or gears by discoloration,accompanied by roughenin
18、g not attributable to mechanical action. ASTM Distress Rating Manual No. 213.1.7 cracked gear tooth, na gear tooth exhibiting a linear fracture of the tooth surface.3.1.8 deposits, nin final drive axles, material of pasty, gummy, or brittle nature adhering to or collecting around any of theworking p
19、arts.ASTM Distress Rating Manual No. 213.1.9 discoloration, non ring and pinion gears, any alteration in the normal color of finished steel surfaces.ASTM Distress Rating Manual No. 213.1.10 pitting, non ring and pinion gears, small irregular cavities in the tooth surface, resulting from the breaking
20、 out of smallareas of surface metal.ASTM Distress Rating Manual No. 213.1.11 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 completely across the
21、tooth surfaces of gears.ASTM Distress Rating Manual No. 213 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4 A
22、vailable from Standardization Documents Order Desk, Bldg 4, Section D, 700 Robbins Avenue, Philadelphia, PA 191115098.5 American Gear Manufacturers Assn. (AGMA), 1500 King St., Suite 201, Alexandria, VA 22314.6 Available from SAE International (SAE), 400 Commonwealth Dr., Warrendale, PA 15096, http:
23、/www.sae.org.7 Formerly known as CRC Manual 21. Available from the ASTM website, www.astm.org, (TMCMNL21).D6121 1723.1.12 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 Dis
24、tress Rating Manual No. 213.1.13 scoring, 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
25、.ASTM Distress Rating Manual No. 213.1.14 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. 213.1.15 spalling, non ring an
26、d pinion gears, the breaking out of flakes of irregular area of the tooth surface, a condition moreextensive than pitting.ASTM Distress Rating Manual No. 213.1.16 surface fatigue, non ring and pinion gears, the failure of the ring gear and pinion material as a result of repeatedsurface or subsurface
27、 stresses that are beyond the endurance limit of the material. It is characterized by the removal of metal andthe formation of cavities.AGMA National Standard3.1.17 wear, non ring and pinion gears, the removal of metal, without evidence of surface fatigue or adhesive wear, resultingin partial or com
28、plete elimination of tool or grinding marks or development of a discernible shoulder ridge at the bottom of thecontact area near the root or at the toe or heel end of pinion tooth contact area (abrasive wear).ASTM Distress Rating Manual No. 214. Summary of Test Method4.1 Prior to each test run, insp
29、ect 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 the charged test unit for 100 min at 440 wheel r/min and 395 l
30、bf-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 conditions dictated by the hardware batch and typecombination
31、(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 gearand pinion to evaluate the performance of the test oil.5. Sign
32、ificance 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 protection can lead to prematuregear or bearing failure, or both.5.2
33、 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 UnitThe test unit is a new complete hypoid truck axle assemb
34、ly less axle shafts, Dana Model 60, 5.86 to 1 ratio.10See Annex A9 for part numbers.8 “Lubricant Service Designations for Automotive Manual Transmissions, Manual Transaxles, and Axles,” available from American Petroleum Institute, 1220 L St. NW,Washington, DC 20005.9 “Laboratory Performance Tests fo
35、r 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. If you are aware of alternativesuppliers, please provide this information to ASTM International Headquarte
36、rs. Your comments will receive careful consideration at a meeting of the responsible technicalcommittee,1 which you may attend.D6121 1736.2 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 enters theho
37、using.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. A5.1 for an example.6.2.3 Test Stand ConfigurationMount the complete assembly in a rigid fixture as shown in Fig. A6.1. Mount the test unit inthe test s
38、tand 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 ThermocoupleDetermine th
39、e thermocouple location on the rear cover using the cover plate temperature sensorlocating device as shown in Fig. A7.1.(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 thermocouple into t
40、he 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 distribute
41、 water over the cover plate and axle housing as shown in Fig. A8.1.Actuate the water control valve by the temperature PID control system. See A9.3.2.1 for L-37 Canadian Version test.(1) Spray nozzles11 shall be any combination of the following part numbers depending on how the system is plumbed: Str
42、aightMale 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 be a 12 in. (12.7 mm) two-way, C lineartrim, air to close, R
43、esearch 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 A9.3.2.2 for L-37 CanadianVersion test.(3) Use only 38 or 12 in. (9.5 mm or 12.7 mm) line m
44、aterial 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. A8.2. The purpose is to contain water and eliminate drafts.(6) Use a locating pin or stop block as an indexing device to ensure that all subsequent
45、 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 test conditions.6.2.6 Dynamometers and Torque Control SystemUse
46、 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 Connecting ShaftsFabricate shafts connecting the dynamometer t
47、o 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 test axle.The shaft shall have a 4 in. 6 0.2 in. (10.1 cm 6
48、0.51 cm) outside diameter with a 0.095 in. 6 0.005 in. (0.24 cm 6 0.013 cm)wall thickness. Shaft and universal joints should be strong enough to handle the torques encountered and shall be dynamically(spin) balanced.6.2.9 Transmission and CouplingCouple the engine to the test unit through a clutch a
49、nd 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 Materials7.1 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 % to 2 % vol), Flash Point (142 F61 C, min) and Color (not darker than +25 on Saybolt Scale or 2
