1、Designation: D2782 02 (Reapproved 2014)240/84Standard Test Method forMeasurement of Extreme-Pressure Properties of LubricatingFluids (Timken Method)1This standard is issued under the fixed designation D2782; the number immediately following the designation indicates the year oforiginal adoption or,
2、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 load-carrying capacity of lubric
3、ating fluids by means of the TimkenExtreme Pressure Tester.NOTE 1This test method is suitable for testing fluids having aviscosity of less than about 5000 cSt (5000 mm2/s) at 40C. For testingfluids having a higher viscosity, refer to Note 5 in 9.1.1.2 The values stated in SI units are to be regarded
4、 asstandard. Because the equipment used in this test method isavailable only in inch-pound units, SI units are omitted whenreferring to the equipment and the test specimens.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibili
5、ty 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 warningstatements are given in 7.1, 7.2, 8.1, 8.2, 9.4, and 9.9.2. Referenced Documents2.1 ASTM Standards:2D2509 Test Method for Mea
6、surement of Load-CarryingCapacity of Lubricating Grease (Timken Method)D4175 Terminology Relating to Petroleum, PetroleumProducts, and LubricantsG40 Terminology Relating to Wear and Erosion2.2 ASTM Adjuncts:Photograph of Test Blocks Showing Scars33. Terminology3.1 Definitions:3.1.1 extreme pressure
7、(EP) additive, n, in a lubricantasubstance that minimizes damage to metal surfaces in contactunder high-stress rubbing conditions. D41753.1.2 lubricant, nany substance interposed between twosurfaces for the purpose of reducing friction or wear betweenthem. G403.1.3 scoring, n, in tribologya severe f
8、orm of wear char-acterized by the formation of extensive grooves and scratchesin the direction of sliding. G403.1.4 wear, ndamage to a solid surface generally involv-ing progressive loss of material, due to relative motion betweenthat surface and a contacting substance or substances. G403.2 Definiti
9、ons of Terms Specific to This Standard:3.2.1 load-carrying capacity of a lubricant as determinedby this test method, the maximum load or pressure that can besustained by the lubricant (when used in the given systemunder specific conditions) without failure of the sliding contactsurfaces as evidenced
10、 by scoring or seizure or asperity weld-ing.3.2.2 OK value, nas determined by this test method, themaximum mass (weight) added to the load lever weight pan, atwhich no scoring or seizure occurs.3.2.3 score value, nas determined by this test method, theminimum mass (weight) added to the load lever we
11、ight pan, atwhich scoring or seizure occurs.3.2.3.1 DiscussionWhen the lubricant film is substantiallymaintained, a smooth scar is obtained on the test block, butwhen there is a breakdown of the lubricant film, scoring orsurface failure of the test block takes place, as shown in Figs.1 and 2. In its
12、 simplest and most recognized form, scoring ischaracterized by the furrowed appearance of a wide scar on the1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.L0.11 on Tribiological
13、Properties of Industrial Fluids andLubricates.Current edition approved May 1, 2014. Published July 2014. Originally approvedin 1969. Last previous edition approved in 2008 as D2782 02 (2008).This test method was adopted as a joint ASTM-IP Standard.This test method was prepared under the joint sponso
14、rship of the AmericanSociety of Lubrication Engineers. Accepted by STLE January 1969. DOI: 10.1520/D2782-02R14.2For 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 s
15、tandards Document Summary page onthe ASTM website.3Available from ASTM International Headquarters. Order Adjunct No.ADJD2509. Original adjunct produced in 1972.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1test block and by excessiv
16、e pick-up of metal on the surface ofthe test cup. The form of surface failure more usuallyencountered, however, consists of a comparatively smoothscar, which shows local damage that usually extends beyondthe width of the scar. Scratches or striations that occur in anotherwise smooth scar and that do
17、 not extend beyond the widthof the scar are not considered as evidence of scoring.3.2.4 seizure or asperity weldinglocalized fusion of metalbetween the rubbing surfaces of the test pieces. Seizure isusually indicated by streaks appearing on the surface of the testcup, an increase in friction and wea
18、r, or unusual noise andvibration. Throughout this test method the term seizure isunderstood to mean seizure or asperity welding.4. Summary of Test Method4.1 The tester is operated with a steel test cup rotatingagainst a steel test block. The rotating speed is 123.71 6 0.77mmin (405.88 6 2.54 ft/min)
19、 which is equivalent to a spindlespeed of 800 6 5 rpm. Fluid samples are preheated to37.8 6 2.8C (100 6 5F) before starting the test.4.2 Two determinations are made: the minimum load (scorevalue) that will rupture the lubricant film being tested betweenthe rotating cup and the stationary block and c
20、ause scoring orseizure; and the maximum load (OK value) at which therotating cup will not rupture the lubricant film and causescoring or seizure between the rotating cup and the stationaryblock.5. Significance and Use5.1 This test method is used widely for the determination ofextreme pressure proper
21、ties for specification purposes. Usersare cautioned to carefully consider the precision and biasstatements herein when establishing specification limits.6. Apparatus6.1 Timken Extreme Pressure Tester,4described in detail inAnnex A1 and illustrated in Fig. 3.6.2 Sample Feed Device,4for supplying the
22、test specimenswith fluid is described in Annex A1.6.3 Loading Mechanism,4for applying and removing theload weights without shock at the uniform rate of0.91 to 1.36 kgs (2 to 3 lb/s).Adetailed description is given inAnnex A1.6.4 Microscope,4low-power (50 to 60) having sufficientclearance under object
23、ive to accommodate the test block. Itshould be fitted with a filar micrometer so that the scar widthmay be measured with an accuracy of 60.05 mm (60.002 in.).6.5 Timer, graduated in minutes and seconds.7. Reagents and Materials7.1 Acetone, reagent grade. (WarningExtremely flam-mable. Harmful when in
24、haled. See A3.1.)7.2 Stoddard Solvent or White Spirit, reagent grade.(WarningFlammable. See A3.2.)7.3 Test Cup,4,5of carburized steel, having a RockwellHardness “C” Scale Number of 58 to 62, or a Vickers HardnessNumber of 653 to 756. The cups have a width of0.514 6 0.002 in., a perimeter of 6.083 6
25、0.009 in., a diameterof 1.938 + 0.001, 0.005 in. and a maximum radial run-out of0.0005 in. The axial surface roughness should lie between 0.51and 0.76 m (20 and 30 in.) C.L.A.7.4 Test Blocks,4,6with test surfaces 0.485 6 0.002 in. wideand 0.750 6 0.016 in. long, of carburized steel, having aRockwell
26、 Hardness “C” Scale Number of 58 to 62, or a VickersHardness Number of 653 to 756. Each block is supplied withfour ground faces and the surface roughness should lie between0.51 and 0.76 m (20 and 30 in.) C.L.A.4The sole source of supply of the apparatus known to the committee at this timeis Falex Co
27、rp., 1020 Airpark Dr., Sugar Grove, IL 60554. If you are aware ofalternative suppliers, please provide this information to ASTM InternationalHeadquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee,1which you may attend.5Available from Falex C
28、orp., under Part No. F-25061.6Available from Falex Corp., under Part No. F-25001.FIG. 1 Test Blocks Showing Various Types of ScarFIG. 2 ScoringD2782 02 (2014)28. Preparation of Apparatus8.1 Clean the apparatus with (1) Stoddard solvent or WhiteSpirit, and (2) acetone and blow dry. (WarningExtremelyf
29、lammable. Harmful when inhaled. See A3.1.) (WarningFlammable. See A3.2.) Flush with approximately 1 L (1 qt)of the fluid to be tested. Discard the flushing fluid. (WarningSince acetone is highly flammable, use the minimum quantity.)8.2 Select a new test cup and block, wash with Stoddardsolvent or Wh
30、ite Spirit (WarningFlammable. See A3.2.)and dry with a clean soft cloth or paper. Immediately beforeuse rinse the test cup and block with acetone and blow themdry. Do not use solvents such as carbon tetrachloride or othersthat may inherently possess load-carrying properties whichmay effect the resul
31、ts.NOTE 2This cleaning may be done in an ultrasonic cleaner.8.3 Assemble the tester carefully (Fig. 4), placing the testcup on the spindle and making certain that it is well seated,drawing it up firmly but avoiding possible distortion fromexcessive tightening (Note 3). Place the test block in the te
32、stblock holder and adjust the levers so that all the knife edges arein proper alignment. Exercise special care in placing the stirrupof the spring-weight platform assembly (selection of whichwill depend on the loading device) in the groove of theload-lever arm to avoid premature shock to the test bl
33、ock whenthe load is applied. To ensure that the test block, test blockholder, and lever arms are properly aligned and seated, coat thetest block and test cup with the lubricant to be tested, and rotatethe machine slowly for a few revolutions either by hand or bysuitable control mechanism. When the p
34、arts are in alignment,the fluid will be wiped off the cup over its entire width.NOTE 3At this point it is recommended that a dial indicator used tocheck the radial run-out of the cup in situ not exceed 0.025 mm (0.001 in.)total indicator movement.9. Procedure9.1 Fill the reservoir of the tester to w
35、ithin 76 mm (3 in.) ofthe top (approximately 3 L or 3 qt) with the fluid to be tested.Preheat the fluid to 37.8 6 2.8C (100 6 5F).NOTE 4The fluid may be heated by the use of an immersion heaterFIG. 3 Timken TesterD2782 02 (2014)3located in the tester reservoir or by heating the fluid prior to fillin
36、g thereservoir. If an immersion heater is used, localized overheating must beavoided. This may be done by stirring or by circulating prior to theassembly of the lever arm.NOTE 5Fluids having a viscosity above about 5000 cSt (5000 mm2/s)at 40C often cannot be tested at the prescribed fluid temperatur
37、e of 37.86 2.8C (100 6 5F) because of inability of the pump to recirculate thefluid at this temperature. However, results from limited cooperative tests,covered in Tables A1.1 and A1.2, indicate that the starting fluid tempera-ture could be increased to 65.6C (150F) to obtain adequate flow withoutaf
38、fecting OK or score values. Testing of such high-viscosity fluids at roomtemperature in the Test Method D2509 grease feeder also appears validbut may be difficult because of fluid leakage.9.2 Set the discharge valve at full open. Allow the lubricantto flood the test cup and block. When the sump is a
39、bout halffilled with the fluid, start the motor and run for 30 s to break-in.If the equipment used is equipped with acceleration control,start the motor and increase the spindle speed gradually toachieve 800 6 5 rpm after 15 s. Run for a further 15 s tocomplete the break-in.9.3 After a break-in peri
40、od of 30 s, start the timer and applyat 8.9 to 13.3 N/s (2 to 3 lbf/s), a load that is less than theexpected score load. In the absence of a better estimate, astarting load of 30 lbf is recommended. The load-lever arm,spring-weight platform assembly is not considered a part of theapplied load. In th
41、e event a lower starting load is used, it mustbe a multiple of 6. Then allow the machine to run at800 6 5 rpm for 10 min 6 15 s after load application isinitiated, unless a score is detected before that period.9.4 If, after the load has been applied, scoring is evident byvibration or noise, stop the
42、 tester at once, turn off the flow oflubricant, and remove the load. Since the excessive heatdeveloped with deep scoring may alter the surface character-istics of the entire block, discard the test block. (WarningThe machine and test pieces may be hot at this point and careshould be exercised in the
43、ir handling.)FIG. 3 (continued)FIG. 4 Assembly of Tester Showing Test PiecesD2782 02 (2014)49.5 If no scoring is detected, allow the tester to run for10 min 6 15 s from the start of the application of the load. Atthe end of the 10-min 6 15-s period, reverse the loading deviceand remove the load from
44、 the lever arm. Turn off the motor,allow the spindle to come to rest, then turn off the flow of fluid.Remove the load lever and inspect the condition of the testblock surface at 1 magnification. Microscopical observationsshall not be used to define when scoring has occurred. Thelubricant has failed
45、at the imposed load if the wear scarindicates any scoring or welding.NOTE 6A microscope may be used to examine the wear scar forfurther information as required in 9.9.9.6 If no score is observed, turn the test block to expose anew surface of contact and, with a new test cup, repeat the test,as in 9.
46、5, at 10-lbf increments until a load that produces a scoreis reached. At this point decrease the load by 5 lbf for the finaldetermination.NOTE 7Before each test in 9.6 9.8 cool the fluid in the reservoir to37.8 6 2.8C (100 6 5F), cool the shaft to less than 65.6C (150F),install a new test cup, and t
47、urn the test block to expose a new surface ofcontact. When seizure has occurred, discard the entire test block sinceexcessive heat, developed when scarring occurs, may alter the surfacecharacteristics of the entire block.9.7 If a score is produced at the 30-lbf load, reduce the loadby 6-lbf decremen
48、ts until no scoring is realized. At this point,increase the load by 3 lbf for the final determination.9.8 When the wear scar evidence at any load stage makesthe definition of the onset of scoring questionable, repeat thetest at the same load. If the second test produces a score, recorda score rating
49、 for this load. Similarly, if the second testproduces no scoring, record a no score rating. If the second testagain yields a questionable result, simply withhold judgment ofthe rating at this load stage and test the fluid at the immediatelynext higher load stage (see Annex A2). Then assign a rating tothe load stage in question that is identical to the rating obtainedat the immediately next higher load stage employed.9.9 After the OK value has been determined, remove the testblock and wash with Stoddard solvent or White Spirit, ri
