1、Designation: D 4693 07An American National StandardStandard Test Method forLow-Temperature Torque of Grease-Lubricated WheelBearings1This standard is issued under the fixed designation D 4693; the number immediately following the designation indicates the year oforiginal adoption or, in the case of
2、revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers the determination of the extentto which a test grease retards the rota
3、tion of a specially-manufactured, spring-loaded, automotive-type wheel bearingassembly when subjected to low temperatures. Torque values,calculated from restraining-force determinations, are a measureof the viscous resistance of the grease. This test method wasdeveloped with greases giving torques o
4、f less than 35 Nmat 40C.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 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 s
5、tandard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 217 Test Methods for Cone Penetration of LubricatingGreaseD 1403 Test Methods for Cone Penetration of LubricatingGrease U
6、sing One-Quarter and One-Half Scale ConeEquipmentD 3527 Test Method for Life Performance of AutomotiveWheel Bearing GreaseD 4175 Terminology Relating to Petroleum, PetroleumProducts, and LubricantsE1 Specification for ASTM Liquid-in-Glass ThermometersE77 Test Method for Inspection and Verification o
7、f Ther-mometersE 220 Test Method for Calibration of Thermocouples ByComparison TechniquesE 230 Specification and Temperature-Electromotive Force(EMF) Tables for Standardized ThermocouplesE 563 Practice for Preparation and Use of an Ice-Point Bathas a Reference TemperatureE 585/E 585M Specification f
8、or Compacted Mineral-Insulated, Metal-Sheathed, Base Metal ThermocoupleCableE 608/E 608M Specification for Mineral-Insulated, Metal-Sheathed Base Metal Thermocouples2.2 Military Standard:3MIL-G-10924F Specification for Automotive and Artillery2.3 Other Standard:Anti-Friction Bearing Manufacturer Ass
9、oc. (AFBMA) Stan-dard 19, 1974 (ANSI B.3.19-1975)3. Terminology3.1 Definitions:3.1.1 automotive wheel bearing grease, na lubricatinggrease specifically formulated to lubricate automotive wheelbearings at relatively high grease temperatures and bearingspeeds. D 35273.1.2 lubricant, nany material inte
10、rposed between twosurfaces that reduces the friction or wear between them.D 41753.1.3 lubricating grease, na semi-fluid to solid product ofa dispersion of a thickener in a liquid lubricant.3.1.3.1 DiscussionThe dispersion of the thickener forms atwo-phase system and immobilizes the liquid lubricant
11、bysurface tension and other physical forces. Other ingredients arecommonly included to impact special properties. D 2173.1.4 thickener, nin lubricating grease, a substance com-posed of finely-divided particles dispersed in a liquid lubricantto form the products structure.3.1.4.1 DiscussionThe solid
12、thickener can be fibers (suchas various metallic soaps) or plates or spheres (such as certainnon-soap thickeners) which are insoluble or, at the most, onlyvery slightly soluble in the liquid lubricant. The generalrequirements are that the solid particles be extremely small,uniformly dispered, and ca
13、pable of forming a relatively stable,gel-like structure with the liquid lubricant. D 2171This test method is under the jurisdiction of Committee D02 on PetroleumProducts and Lubricants and is the direct responsibility of Subcommittee D02.G0 onLubricating Grease.Current edition approved Nov. 1, 2007.
14、 Published December 2007. Originallyapproved in 1987. Last previous edition approved in 2003 as D 469303.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standar
15、ds Document Summary page onthe ASTM website.3Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Bo
16、x C700, West Conshohocken, PA 19428-2959, United States.4. Summary of Test Method4.1 A freshly stirred and worked sample of test grease ispacked into the bearings of a specially-manufactured,automotive-type spindle-bearings-hub assembly. The assemblyis heated and then cold soaked at 40C, unless anot
17、her testtemperature is specified by the grease specification. Thespindle is rotated at 1 rpm and the torque required to preventrotation of the hub is measured at 60 s.5. Significance and Use5.1 This test method differentiates among greases havingdistinctly different low-temperature characteristics.
18、This test isused for specification purposes and correlates with its precursorwhich has been used to predict the performance of greases inautomotive wheel bearings in low-temperature service.4It isthe responsibility of the user to determine the correlation withother types of service.6. Apparatus6.1 L
19、ow-Temperature Wheel Bearing Torque Apparatus,5,6illustrated in Fig. 1.NOTE 1Several apparatus configurations are available, differingmainly in the drive system. For example, with large cold chambers, aunitized apparatus (see Fig. 1) can be used totally within the cold chamber.With small cold chambe
20、rs, the drive system can be mounted externallyand only the test unit subjected to low temperature. Regardless of theexact configuration, the essential apparatus consists of a 1/3 hp electricmotor connected to a gear reducer by means of a timing belt and pulleys,which drive a specially-manufactured s
21、pindle-bearings-hub assemblyequipped with a spring-loading mechanism. For apparatus containedtotally within the cold chamber, the drive system should be prepared byreplacing the grease in the motor bearings with a suitable low-temperaturegrease (1 Nm torque at 40C), such as one meeting the requireme
22、nts ofSpecification MIL-G-10924F or similar, and the lubricant in the gearreducer should be replaced with a suitable low-temperature ( 50C pourpoint) worm-gear lubricant.6,7In addition, if not already so-equipped,large-diameter (152 mm), narrow-width (13 mm) timing pulleys and asuitable timing belt
23、should be used.6.2 Torque Measuring System, consisting of a strain-gageload cell with a matching bridge-balance unit,6,8a suitablestrip-chart recorder to record the load-cell output, and a seriesof weights (up to 20 kg, at least) suitable for load-cellcalibration.NOTE 2In order to calculate torque f
24、rom force measurements, theload cell should be located a known distance from the test-unit centerline;100 mm is convenient. A convenient way to do this is to centrally drill a1.78-mm diameter hole (No. 50 drill) in the torque arm, 100 mm from thespindle centerline; temporarily replace the load cell
25、contact with a secondcontact having a 1.59-mm diameter pin (soldered in place) extendingabout 5 mm above the contact point; position the load cell to permitinsertion of the pin in the torque-arm hole; secure the position of the loadcell by tightening the clamping screws; replace pin contact with ori
26、ginalcontact before running test.6.3 Temperature Measuring System, consisting of Type T(preferred) or Type J (acceptable), 3.18-mm diameter metal-sheathed, grounded thermocouples meeting SpecificationsE 585/E 585M and E 608/E 608M and conforming to the4Verdura, T. M., “Performance of Service Station
27、 Wheel Bearing Greases in aNew Low-Temperature Test,” NLGI Spokesman 35 10-21 (1971).5The sole source of supply of the apparatus known to the committee at this timeis available from Koehler Instrument Company, Inc., 1595 Sycamore Avenue,Bohemia, NY 11716.6If you are aware of alternative suppliers, p
28、lease provide this information toASTM International Headquarters. Your comments will receive careful consider-ation at a meeting of the responsible technical committee,1which you may attend.7The sole source of supply of the apparatus known to the committee at this timeis Mobil SHC 624 (or similar),
29、available from Mobil Oil Corporation, 3225 GallowsRd., Fairfax, VA 22037.8The sole source of supply of the apparatus known to the committee at this timeis a Model 3167-50 load cell and matching electronic circuitry, available fromLebow Associates, Inc., 1728 Maplelawn, Troy, MI 48062.FIG. 1 Low-Temp
30、erature Torque ApparatusD4693072special limits of error defined in Table 1 of Specification E 230;a suitable potentiometer, satisfying the requirements forGroups B or C as described in Test Method E 220; an ASTM73C precision thermometer meeting Specification E1, certified(traceable to National Insti
31、tute of Standards and Technologycertification) or verified and calibrated according to TestMethod E77; a suitable comparator as described in TestMethod E77; and an ice bath prepared according to PracticeE 563.NOTE 3Other temperature-measuring instrumentation, such as a pre-cision platinum resistance
32、 thermometer, may be used instead of thermo-couples, providing the limits of error are within those defined inSpecification E 230.6.4 Test BearingUse LM67010-LM67048 and LM11910-LM11949 (AFBMA Standard 19) inboard and outboard ta-pered roller bearings, respectively.6.5 Low-Temperature Test Chamber,
33、equipped with internalfan, and capable of maintaining the spindle at 40 6 0.5C,and with sufficient capacity to cool the spindle at the rateshown in Fig. 2(A) and Fig. 2(B).6.6 Laboratory Oven, forced air, capable of maintaining 706 3C.6.7 Grease Packer, as described in Test Method D 3527 orequivalen
34、t.6.8 Ultrasonic Cleaner.6,97. Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Societywhere
35、 such specifications are available.10Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.7.2 Ethylene Glycol, commercial automotive antifreeze.(WarningModerately toxic. Can be ha
36、rmful if inhaled,swallowed or absorbed through skin. Contact can irritate eyes,or mucosa.)7.3 n-Heptane, reagent grade. (WarningFlammable.Harmful if inhaled.)7.3.1 n-Heptane is recommended as the cleaning solvent forthe test bearings, as a replacement for the more hazardoussolvents used previously (
37、chloroform and 1,1,1tricholoroet-hane). However, the precision of the test has not been estab-lished with the use of n-heptane. In referee situations, contrac-tual parties should agree on the acceptability of n-heptane forthe test.7.4 Chloroform, reagent grade. (WarningHealth hazard.)7.4.1 This test
38、 method and the precision statement wereoriginally developed using chloroform as the cleaning solventfor the test bearings. However, the use of chloroform isdiscouraged, because of its known health hazards. If it isdeemed necessary to use chloroform in a referee situation, it isthe responsibility of
39、 the contractual parties to ensure thatproper precautions are taken.7.5 1,1,1-Trichloroethane, reagent grade. (WarningHealth hazard.)7.5.1 This test method was revised in the past to specify theuse of 1,1,1trichloroethane as a replacement for chloroform.However, 1,1,1trichloroethane also has health
40、and environ-mental risks associated with its use. Therefore, its use isdiscouraged for this test method, and it is recommended thatn-heptane is used instead. If it is deemed necessary to use1,1,1trichloroethane in a referee situation, it is the responsi-bility of the contractual parties to ensure th
41、at the properprecautions are taken.NOTE 4This test method (and the precision values) was originallydeveloped using chloroform. This was subsequently replaced by 1,1,1-trichloroethane which was declared an ozone depleting substance by theU.S. Environmental ProtectionAgency (EPA). Federal regulations
42、ban theproduction of this material after December 31, 1995, but existing stocksmay continue to be used. Currently there are no EPArestrictions on the useof chloroform, but the user should be aware of its health hazards, if it isused. No other solvent (including n-heptane) intended as a substitute fo
43、r1,1,1-trichloroethane in this test method has been cooperatively evaluated.(WarningIf the functionally equivalent solvent is flammable or a healthhazard, proper precautions should be taken.)8. Calibration8.1 Torque Calibration:8.1.1 Place the load cell in the cold chamber at 40C andallow it to come
44、 to temperature equilibrium. Electrically nullthe load cell and recording potentiometer using the adjustingpotentiometer of the matching network. Adjust or standardizethe range potentiometer as needed to achieve the desiredzero-point and full-scale calibration. Select a millivolt range onthe recordi
45、ng potentiometer, and record pen displacement as aknown force is applied to the load cell. (It may be necessary tofabricate a platform to attach to the load cell to support thecalibrating weights.) Apply several forces (up to about 200 Nor more) in stepwise fashion while recording pen displacementas
46、 a function of applied force. Calibrate the other millivoltranges in similar fashion until limited by either maximumdisplacement or maximum load. Remove forces stepwise todetermine possible hysteresis.8.1.2 Construct a plot of pen displacement as a function offorce for each millivolt range. Use thes
47、e plots for the subse-quent determination of torque for the test greases. Ordinarily,the plots will be linear, and simple conversion factors can becalculated.9The sole source of supply of the apparatus known to the committee at this timeis Bransonic 220, having a capacity of about 4 L operating at a
48、n output frequencyof about 55 kHz, with a power input of about 125 W, available from BransonUltrasonics Corporation, 41 Eagle Rd., Danbury, CT 06813-1961.10Reagent Chemicals, American Chemical Society Specifications , AmericanChemical Society, Washington, DC. For suggestions on the testing of reagen
49、ts notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.TABLE 1 Torque Test Results at 40C with NLGI ReferenceSystem A (Batch 3)Mean value 3.7 NmStandard deviation 0.67 NmConfidence limits, 95 %:Lower 3.2Upper 4.1D4693073NOTE 5Data logging software may be uesd to collect this data.8.1.3 This calibration need be done only at the time of initialsetup and when occasi
