1、Designation: D7452 10Standard Test Method forEvaluation of the Load Carrying Properties of LubricantsUsed for Final Drive Axles, Under Conditions of High Speedand Shock Loading1This standard is issued under the fixed designation D7452; the number immediately following the designation indicates the y
2、ear 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 covers the determination of the anti
3、-scoring properties of final drive axle lubricating oils whensubjected to high-speed and shock conditions. This test methodis commonly referred to as the L-42 test.21.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to
4、 SI units that are provided for information onlyand are not considered standard.1.2.1 ExceptionsSI units are provided for all parametersexcept where there is no direct equivalent such as the units forscrew threads, National Pipe Threads/diameters, tubing size,and single source equipment suppliers.1.
5、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. Specific warning
6、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 Test Data toDetermine Conformance with Specifications2.2 Society of Automotive
7、Engineers Standards:4SAE J308 Information Report on Axle and Manual Trans-mission LubricantsSAE J2360 Lubricating Oil, Gear Multipurpose (Metric)Military Use3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 coast side, nthe convex side of the pinion and theconcave side of the ri
8、ng gear which are in contact duringdeceleration in a forward gear. CRC Manual 2153.1.2 drive side, nthe concave side of the pinion and theconvex side of the ring gear which are in contact duringacceleration in a forward gear. CRC Manual 2153.1.3 scoring, non the ring and the pinion gear teeth, thedi
9、splacement of metal by local momentary welding from thegear tooth, resulting in the development of a matt, or frosteddull surface. CRC Manual 2154. Summary of Test Method4.1 Charge a specially prepared light duty hypoid rear axle(Dana Model 44 ASTM Part No. 044AA100-1)6with thelubricant sample to be
10、 tested (see 10.1). Mount the axlebetween two load absorbing dynamometers which are drivenwith a V-8 gasoline engine through a manual transmission.4.2 Condition the test axle with light loads at differentspeed, torque and temperature conditions on both the drive andcoast sides of the gears. (Warning
11、High-speed rotatingequipment, electrical shock, high-temperature surfaces.) Afterconditioning, subject the test axle to high speed and shockloadings at higher temperatures.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsi
12、bility of SubcommitteeD02.B0.03 on Automotive Gear Lubricants percent output adjustable.6.6.4 Axle CoolingUse three spray nozzles to distributewater over the cover plate and axle housing as shown in Fig.A2.2. Actuate the water control valve by the temperature PIDcontrol system.6.6.4.1 Depending on h
13、ow the system is plumbed, use spraynozzles in any combination of the following part numbers:Straight Male NPT (Part No. 3/8GG-SS22), 90 Male NPT(Part No. 3/8GGA-SS22), Straight Female NPT (Part No.3/8G-SS22), and 90 Female NPT (Part No. 3/8GA-SS22).8,96.6.4.2 Use a single control valve to control th
14、e coolingwater supply. The control shall be a12 in. (12.7 mm) two-way,C linear 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 PIDloop control for each version is not permit
15、ted. See Annex A1.6.6.4.3 Use only38 or12 in. (9.5 mm or 12.7 mm) linematerial to the spray nozzles.6.6.4.4 Use a minimum supply water pressure of 25 psig(172 kPa) to the control valve.6.6.4.5 Use an axle containment box as shown in Fig.A2.10. The purpose is to contain water.6.6.4.6 Use a locating p
16、in or stop block as an indexingdevice to ensure that all subsequent axle installations areconsistently installed perpendicular with the axle housingcover to engine and transmission drive-shaft centerline.6.7 Torque MeterInclude in the test equipment a torquemeter installed in the drive shaft (see Fi
17、gs. A2.3-A2.5)tomeasure the torque applied to the pinion. Install a Himmelsteininline torque meter Model numbers MCRT28061T(1-4) orMCRT2661TN(1-4)9,10without a foot mount and a range of10 000 lb-in. (1130 Nm) shall be installed to measure piniontorque. Additional suffix letters only indicate allowab
18、le op-tions.6.8 Signal ConditioningUse a Himmelstein Models 701or 711 strain gage conditioner for signal conditioning. Set thelow pass cut-off frequency at 10 Hz.6.9 Digital Data Acquisition SystemSystem requires ca-pability of measuring a minimum of five channels at samplingfrequencies outlined in
19、Section 10.6.9.1 Do not use hardware or software filtering for thepinion torque channel during data acquisition periods of thetest.6.10 DynamometersTwo axle dynamometers (MidwestDynamatic, Model 3232)9,11with suitable control equipmentcapable of maintaining specified test conditions.6.11 Engine Spee
20、d ControlSystem requires a device tomaintain steady state conditions and also provide adjustablethrottle acceleration and deceleration rates to attain specifiedshock loading torques.6.11.1 Throttle Controller SystemUse a Foxboro/JordanController, Model AD7530.9,12Use a power transformer fromAcme Ele
21、ctric Corp. PN T-1-81058 or equivalent, primary7API Publication 1560, Lubricant Service Designations for Automotive ManualTransmissions, Manual Transaxles, and Axles, American Petroleum Institute,Washington, DC.8The sole source supply of the apparatus known to the committee at this time isSpray Syst
22、ems Company, and can be purchased through E. I. Pfaff Company, 3443Edwards Road, Suite D, Cincinnati, OH 45208.9If you are aware of alternative suppliers, please provide this information toASTM International Headquarters. Your comments will receive careful consider-ation at a meeting of the responsi
23、ble technical committee,1which you may attend.10The sole source supply of the apparatus known to the committee at this timeis S. Himmelstein and Company, 2490 Pembroke Avenue, Hoffman Estates, IL60195.11Available from Dyne Systems, P.O. Box 18 W209 N17391 Industrial Drive,Jackson, WI 53037.12Availab
24、le from Fox/Jordan, Inc., 5607 West Douglas Avenue, Milwaukee, WI53218.D7452 102volts 120X240, secondary volts (120 V primary by 240 Vsecondary), 16/32 (13 mm) center tap, 0.500 kVA (0.5 kW) inconjunction with the Foxboro/Jordan Controller.6.12 Connecting ShaftsUse connecting shafts of equallength 6
25、 1 in. (25.4 mm) and less than 30 in. (762 mm) longfrom flange face to flange face. Use a tubing diameter of 3.5 60.2 in. (88.9 mm 6 5.1 mm) OD, with a wall thickness of 0.0956 0.005 in. (2.41 mm 6 0.13 mm) if tubing is required tofabricate the shafts. Ensure the shafts are dynamically (spin)balance
26、d and strong enough to handle torques up to 2100 lbf-ft(2847 Nm). Use an operating angle of (0 6 0.5).6.13 Power TrainThe power train consists of a gasolinepowered V-8 GM performance Ramjet 5.7 L marine enginecoupled with a five speed manual transmission capable ofsupplying specified shock loading t
27、orques. The engine andtransmission operating angle shall be (0 6 0.5).6.13.1 All recommended replacement parts are availablethrough local General Motors dealers. A list of these replace-ment parts are shown in Table 1. Do not make modifications tothe engine that would affect the engines factory disp
28、lacementor compression ratio.6.14 Drive ShaftWelded steel tubing, 3.5 6 0.2 in. (90mm 6 5.1 mm) outside diameter, 0.095 6 0.005 in. (2.41 mm6 0.13 mm) wall thickness, 34.5 6 1 in. (880 mm 6 25 mm)long from center weld to center weld. (See Figs. A2.3-A2.5.)Dynamically (spin) balance the drive shaft a
29、nd torque meter.The operating angle shall be (0 6 0.5).6.14.1 Transmission U-Joint(Spicer 5-178X).136.14.2 Pinion U-Joint(Spicer 5-153X).6.14.3 Flange YokeConnects transmission yoke throughu-joint to drive shaft.6.14.4 Pinion Drive Shaft Slip YokeConnects the driveshaft through the u-joint to the ax
30、le yoke.6.14.5 Flange AdaptorManufacture flange adapter tospecifications in Figs. A2.4 and A2.5.6.15 Spring PlateManufacture spring plates to specifica-tion as shown in Fig. A2.8.6.16 Spring Plate Rod ConnectionMount a rod connect-ing the spring plate to the gear stand using12 in. (13 mm)spherical r
31、od ends. See Figs. A2.6 and A2.7.7. Reagents and Materials7.1 Sealing CompoundWhere necessary, use PermatexNo. 2 or equivalent.7.2 Cleaning SolventUse solvent meeting ASTM D235Type II, Class C requirements forAromatic Content (0 to 2) vol%, Flash Point (142F/61 C, min) and Color (not darker than+25
32、on Saybolt Scale or 25 on Pt-Co Scale). (WarningHealth hazard, combustible.) Obtain a Certificate of Analysisfor each batch of solvent from the supplier.7.3 Contact Pattern Marking CompoundWayne MetalWorking Compound # M 99B 111A14or equivalent.7.4 Test OilUse 3.5 pt (1655 mL) of test lubricant.8. P
33、reparation of Apparatus8.1 Cleaning of Reusable HardwareClean as necessarywith cleaning solvent (see 7.2) all reusable parts including:axle shafts, thermocouples, axle housing cover, and all associ-ated drain pans and funnels used for the addition of andcollection of test oil.8.2 Preparation of Axle
34、:8.2.1 Pretest contact pattern procedure (see Annex A6).8.2.2 Record break and turn.8.2.3 Record the backlash reported from the manufacturer.The readings shall be between 0.004 and 0.012 in. (0.102 to0.305 mm).8.2.3.1 Measure and record backlash at four equally spacedlocations. Report the average an
35、d the four readings.8.2.4 Proceed to 8.2.9 if contact pattern and backlash areacceptable. Proceed to 8.2.5 if the contact pattern or backlashneeds adjustment.8.2.5 Follow Dana Model 44 Maintenance Manual6ifcontact pattern or backlash needs to be adjusted.8.2.6 Assemble the gear unit using Dana Model
36、 44 Main-tenance Manual.6Apply gear contact pattern grease on thedrive and coast side of the ring. Place a 30 6 5 lbf-ft (40.7 66.8 Nm) turning torque on the ring and pinion. Rotate ring andpinion through the gear contact pattern grease on the drive andcoast side.8.2.7 Proceed to 8.2.8 if the contac
37、t pattern and backlash areacceptable. If the contact pattern requires further adjustment,repeat 8.2.5 and 8.2.6 until an acceptable pattern is obtained.8.2.8 Measure and record backlash at four equally spacedlocations. Report the average and the four readings.8.2.9 Clean the gear with cleaning solve
38、nt (see 7.2) whengear contact pattern and backlash are at acceptable levels.8.2.10 CleaningWash the test unit in cleaning solvent (see7.2), paying particular attention to the pinion bearing to removeall preservative oil. Blow dry with clean dry compressed air.8.2.11 Install axle shafts in test unit.
39、13Available from any local drive shaft supplier.14The gear marking compound is made by Wayne Metal Working Company.TABLE 1 Recommended Power Train Replacement Parts ListParts Part NumberRamjet Engine Includes ECM 12495515Five Speed Transmission 15747134Bell Housing 15998496Clutch Assembly 15002591Th
40、row Out Bearing 15705563Dip Stick 10190942Dip Stick Tube 12552920Flywheel 10105832Flywheel Bolt (6 req.) 12337973Pilot Bearing 14061685Master Cylinder 15727261Actuating Cylinder 15046288Pulley, Water Pump 14023155Pulley, Crankshaft 14023147Belt 9433720Starter 10496873Engine Control Unit 12489488Thro
41、ttle Body from 2000 Corvette. 17113669Throttle Body TPS Connector P/N 12116247Throttle Body Actuator Motor Connector P/N 12167121K where: (1) yyyyym-mdd is the date the calibration sequence is started, and (2) xisa number that starts with one and is incremented each time achange is made that require
42、s that calibration sequence to bestarted over.13.5.1 Changing the torque settings is an example of achange that would require the calibration sequence to startover.14. Precision and Bias14.1 Precision:14.1.1 Test precision is established on the basis of opera-tionally valid reference oil test result
43、s monitored by the TMC.14.1.2 Intermediate Precision ConditionsConditionswhere test results are obtained with the same test method usingthe same oil, with changing conditions such as operators,measuring equipment, test stands, test engines and time.NOTE 2Intermediate precision is the appropriate ter
44、m for this testmethod rather than repeatability, which defines more rigorous within-laboratory conditions.14.1.2.1 Intermediate Precision Limit (i.p.)The differencebetween two results obtained under intermediate precisionconditions that would, in the long run, in the normal andcorrect conduct of the
45、 test method, exceed the values shown inTable 2 in only one case in twenty. When only a single testresult is available, the Intermediate Precision Limit can be usedto calculate a range (test result 6 Intermediate Precision Limit)outside of which a second test result would be expected to fallabout on
46、e time in twenty.14.1.3 Reproducibility ConditionsConditions where testresults are obtained with the same test method using the sametest oil in different laboratories with different operators usingdifferent equipment.14.1.3.1 Reproducibility Limit (R)The difference betweentwo results obtained under
47、reproducibility conditions thatwould, in the long run, in the normal and correct conduct of thetest method, exceed the values shown in Table 2 in only onecase in twenty. When only a single test result is available, theReproducibility Limit can be used to calculate a range (testresult 6 Reproducibili
48、ty Limit) outside of which a second testresult would be expected to fall about one time in twenty.14.2 BiasNo estimate of bias is possible, as the behaviorof a lubricant is determined only under the specific conditionsof the test and no absolute standards exist.15. Keywords15.1 automotive gear oils;
49、 extreme pressure lubricants; finaldrive axle; hypoid gear lubricants; L-42TABLE 2 Reference Oil StatisticsAVariable, MeritsIntermediate Precision Reproducibilitysi.p.Bi.p.CsRBRCScoring 5.49 15.37 5.49 15.37AThese statistics are based on results obtained on TMC Reference Oil 116 asof May 7, 2007.Bs = standard deviations.CThis value is obtained by multiplying the standard deviation by 2.8.D7452 108ANNEXES(Mandatory Information)A1. L-42 TEST VERSIONSA1.1 Test VersionsThis test method has two commonlyused versions. The test procedures and c
