1、Designation: D6121 12aD6121 12bStandard 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 indicate
2、s 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 t
3、he 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 (Cana
4、dian) 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
5、.3 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 st
6、andard.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 determ
7、ine 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
8、Test 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 Lub
9、ricating Oil, Gear Multipurpose (Metric) Military Use3. Terminology3.1 Definitions of Terms Specific to This Standard:1 This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products and Lubricants and is the direct responsibility of Subcommittee D02.B0.03on Automotive Gear L
10、ubricants 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 somepart of
11、 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 polishedcondition. A
12、STM 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 tooth surf
13、ace 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 general alt
14、eration 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 of thework
15、ing 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 DistressRating Manual No. 213.1.9 pitting, non ring and pinion gears, small irregular cavities in the tooth surface, resulting from the bre
16、aking 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 completely acros
17、s the tooth surfaces of gears. ASTMDistress 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, non ring
18、 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 scratch
19、ing, 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 of ir
20、regular 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 limit o
21、f 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 marks or
22、 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 ManualNo. 214. Summary of Test Method4.1 Prior to each test run, inspect the test unit (final axle assembly) and me
23、asure and record confirming manufacturingspecifications.4.2 Begin the test when the axle assembly is installed on the test stand and charged with test lubricant.7 Formerly known as CRC Manual 21. Available from the ASTM website, www.astm.org, (TMCMNL21).D6121 12b24.3 Gear Conditioning PhaseRun the c
24、harged test unit for 100 min at 440 wheel r/min and 395 lbf-ft (535 N-m)Nm) torqueper wheel, maintaining an axle sump temperature of 297F (147C).(147 C). (WarningHigh-speed rotating equipment,electrical shock, high-temperature surfaces.)4.4 Gear Test PhaseNext, run the test unit for 24 h at 80 wheel
25、 r/min, 1740 lbf-ft. (2359 N-m)Nm) torque per wheel and anaxle sump temperature of 275F (135C).(135 C). (WarningSee 4.3.)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, and rate for various forms of
26、distress. Use the condition of the ring gearand 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-s
27、peed, high-torque conditions. Lack of protection 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-P
28、RF-2105E.5.2.5 SAE J2360.6. Apparatus6.1 Test 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 t
29、est and arrange the vent so that no water enters thehousing.6.2.2 Axle CoverThe axle cover has a 3.5-in. (8.9-cm) (8.9 cm) inspection port installed, as shown in Fig. A2.1. This allowsfilling the axle and provides a means for inspecting the axle after the gear condition phase (see 10.1). Install a t
30、hermocouple, asdescribed in 6.2.4.1.6.2.3 Test Stand ConfigurationMount the complete assembly in a rigid fixture as shown in Fig. A3.1. Mount the test unit inthe test stand with pinion and axle shaft centerlines horizontal.6.2.4 Temperature ControlThe test axle housing shall include a means of maint
31、aining the lubricant at a specified temperature.This shall include a thermocouple, a temperature recording system, and a cooling method.6.2.4.1 ThermocoupleDetermine the thermocouple location on the rear cover using the cover plate temperature sensorlocating device as shown in Fig. A4.1.(1) Install
32、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 the cover plate until the thermocouple tip is flush with the flat surface.(2) Lock the thermocouple into place.6.2.4.2 Temperature Re
33、cording 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 water over the cover plate and axle housing as shown in Fig. A5.1.Actuate the water control valve by the temperature PID control sy
34、stem. See A6.3.2.1 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: 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
35、(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, Research Control valve. Use a single PID loop to maintain the axle lubricant temperature control for both theStandard and Canadian ve
36、rsion test.Aseparate PID loop control for each version is not permitted. See A6.3.2.2 for L-37 CanadianVersion test.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
37、“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. If you are aware of alternativesuppliers, please provide this information
38、to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsible technicalcommittee,1 which you may attend.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 purc
39、hased through E.I. PfaffCompany, 3443 Edwards Road, Suite D, Cincinnati, OH 45208. If you are aware 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
40、 you may attend.D6121 12b3(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
41、locating pin or stop 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
42、of maintaining test 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.
43、2.7 Dynamometer Connecting 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
44、 transmission and test axle.The shaft shall have a 4 6 0.2-in. (10.1 cm 6 0.51-cm)0.51 cm) outside diameter with a 0.095 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
45、Transmission and CouplingCouple 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 condition
46、s.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(0-2% vol), Flash Point (142F/61C, min) and Color (not darker than +25 on Saybolt S
47、cale or 25 on Pt-Co Scale).(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 a
48、ll associated drain pans and funnels used for the addition of and collection of test oil.8.2 Preparation of Axle:8.2.1 Record the “as received” drive side contact 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
49、F+1 are considered acceptable.Any Note any adjustments that are madeto the axle prior to testing shall be noted in the comments section of the test report. Axle Test labs pattern and report, in the testreport, axle housings from prior gear batches that do not have contact pattern markings shall be patterned and reported by the testlabs in the test report.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
