1、Designation: D 2782 02 (Reapproved 2008)240/84An American National StandardStandard Test Method forMeasurement of Extreme-Pressure Properties of LubricatingFluids (Timken Method)1This standard is issued under the fixed designation D 2782; the number immediately following the designation indicates th
2、e 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. Scope1.1 This test method covers the determination of the l
3、oad-carrying capacity of lubricating 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
4、 in SI units are to be regarded 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
5、 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 warningstatements are given in 7.1, 7.2, 8.1, 8.2, 9.4, and 9.9.2. Referenced Documents2.1 ASTM Stand
6、ards:2D 2509 Test Method for Measurement of Load-CarryingCapacity of Lubricating Grease (Timken Method)D 4175 Terminology Relating to Petroleum, PetroleumProducts, and LubricantsG40 Terminology Relating to Wear and Erosion2.2 ASTM Adjuncts:Photograph of Test Blocks Showing Scars33. Terminology3.1 De
7、finitions:3.1.1 extreme pressure (EP) additive, n, in a lubricantasubstance that minimizes damage to metal surfaces in contactunder high-stress rubbing conditions. D 41753.1.2 lubricant, nany substance interposed between twosurfaces for the purpose of reducing friction or wear betweenthem. G403.1.3
8、scoring, n, in tribologya severe form of wearcharacterized by the formation of extensive grooves andscratches in 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 substanc
9、e or substances. G403.2 Definitions of Terms Specific to This Standard:3.2.1 load-carrying capacity of a lubricantas 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 slidi
10、ng contactsurfaces as evidenced 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 (wei
11、ght) added to the load lever weight 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, a
12、s shown in Figs.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.L0.11 on Tribiological Properties of Industrial Fluids and Lubricants.Current edition approved May 1, 2008. Published August 2008.
13、 Originallyapproved in 1969. Last previous edition approved in 2002 as D 2782021.This test method was adopted as a joint ASTM-IP Standard.This test method was prepared under the joint sponsorship of the AmericanSociety of Lubrication Engineers. Accepted by STLE January 1969.2For referenced ASTM stan
14、dards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from ASTM International Headquarters. Order Adjunct No.ADJD2509. Original a
15、djunct produced in 1972.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.1 and 2. In its simplest and most recognized form, scoring ischaracterized by the furrowed appearance of a wide scar on thetest block and by excessive pick-up of
16、 metal on the surface ofthe test cup. The form of surface failure more usually encoun-tered, however, consists of a comparatively smooth scar, whichshows local damage that usually extends beyond the width ofthe scar. Scratches or striations that occur in an otherwisesmooth scar and that do not exten
17、d beyond the width of the scarare 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 wear, or unus
18、ual 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 0.77m/min (405.88 6 2.54 ft/min) which is
19、 equivalent to a spindlespeed of 800 6 5 rpm. Fluid samples are preheated to 37.8 62.8C (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 cause scor
20、ing 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 properties for
21、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 test spec
22、imenswith fluid is described in Annex A1.6.3 Loading Mechanism,4for applying and removing theload weights without shock at the uniform rate of 0.91 to 1.36kg/s (2 to 3 lb/s). A detailed description is given in Annex A1.6.4 Microscope,4low-power (503 to 603) having sufficientclearance under objective
23、 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 inhal
24、ed. 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 of 0.514 6 0.002in., a perimeter of 6.083 6 0.00
25、9 in., a diameter of1.938 + 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 Har
26、dness “C” Scale Number of 58 to 62, or aVickersHardness 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.8. Preparation of Apparatus8.1 Clean the apparatus with (1) Stoddard solvent or WhiteSpirit, an
27、d (2) acetone and blow dry. (WarningExtremely4The sole source of supply of the apparatus known to the committee at this timeis Falex Corp., 1020 Airpark Dr., Sugar Grove, IL 60554. If you are aware ofalternative suppliers, please provide this information to ASTM InternationalHeadquarters. Your comme
28、nts will receive careful consideration at a meeting of theresponsible technical committee,1which you may attend.5Available from Falex Corp., under Part No. F-25061.6Available from Falex Corp., under Part No. F-25001.FIG. 1 Test Blocks Showing Various Types of ScarFIG. 2 ScoringD 2782 02 (2008)2flamm
29、able. Harmful when inhaled. See A3.1.) (WarningFlammable. See A3.2.) Flush with approximately 1 L (1 qt) ofthe 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 White
30、Spirit (WarningFlammable. SeeA3.2.) anddry with a clean soft cloth or paper. Immediately before userinse the test cup and block with acetone and blow them dry.Do not use solvents such as carbon tetrachloride or others thatmay inherently possess load-carrying properties which mayeffect the results.NO
31、TE 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 testblo
32、ck 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 block w
33、henthe 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 parts
34、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 within
35、 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 heaterlocated in the tester reservoir or by heating the fluid prior to filling thereservoir. If an immersion heater is
36、 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)FIG. 3 Timken TesterD 2782 02 (2008)3at 40C often cannot be tested at the prescribed fluid temperature of
37、 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 withoutaffect
38、ing OK or score values. Testing of such high-viscosity fluids at roomtemperature in the Test Method D 2509 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 abou
39、t 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 period
40、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 the e
41、vent a lower starting load is used, it mustbe a multiple of 6. Then allow the machine to run at 800 6 5rpm for 10 min 6 15 s after load application is initiated, unlessa score is detected before that period.9.4 If, after the load has been applied, scoring is evident byvibration or noise, stop the te
42、ster 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 their
43、handling.)9.5 If no scoring is detected, allow the tester to run for 10min 6 15 s from the start of the application of the load. At theend of the 10-min 6 15-s period, reverse the loading deviceand remove the load from the lever arm. Turn off the motor,FIG. 3 (continued)FIG. 4 Assembly of Tester Sho
44、wing Test PiecesD 2782 02 (2008)4allow 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 13 magnification. Microscopical observationsshall not be used to define when scoring has occurred. Thelubricant has failed a
45、t 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 9.5
46、, 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 tu
47、rn 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 decrement
48、s 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, rinsewith
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