1、Designation: D2782 02 (Reapproved 2014)1D2782 17Standard 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 o
2、r, 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 NOTEThe IP logo and designation were removed and footnote 1 was corrected editorially in
3、 July 2016.1. Scope1.1 This test method covers the determination of the load-carrying capacity of lubricating fluids by means of the TimkenExtreme Pressure Tester.NOTE 1This test method is suitable for testing fluids having a viscosity of less than about 5000 cSt (5000 mm2/s) at 40 C. For testing fl
4、uids havinga higher viscosity, refer to Note 5 in 9.1.1.2 The values stated in SI units are to be regarded as standard. Because the equipment used in this test method is available onlyin inch-pound units, SI units are omitted when referring to the equipment and the test specimens.1.3 This standard d
5、oes 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 safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use. Specif
6、ic warning statements are given in 7.1, 7.2, 8.1, 8.2, 9.4, and 9.9.1.4 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommenda
7、tions issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D2509 Test Method for Measurement of Load-Carrying Capacity of Lubricating Grease (Timken Method)D4175 Terminology Relating to Petroleum Products, Liquid Fuels, and Lubr
8、icantsG40 Terminology Relating to Wear and Erosion2.2 ASTM Adjuncts:Photograph of Test Blocks Showing Scars33. Terminology3.1 Definitions:3.1.1 extreme pressure (EP) additive, n, in a lubricanta substance that minimizes damage to metal surfaces in contact underhigh-stress rubbing conditions. D41753.
9、1.2 lubricant, nany substance interposed between two surfaces for the purpose of reducing friction or wear between them.G403.1.3 scoring, n, in tribologya severe form of wear characterized by the formation of extensive grooves and scratches in thedirection of sliding. G403.1.4 wear, ndamage to a sol
10、id surface generally involving progressive loss of material, due to relative motion between thatsurface and a contacting substance or substances. G403.2 Definitions of Terms Specific to This Standard:1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuel
11、s, and Lubricants and is the direct responsibility of SubcommitteeD02.L0.11 on Tribological Properties of Industrial Fluids and Lubricates.Current edition approved May 1, 2014Dec. 1, 2017. Published July 2014December 2017. Originally approved in 1969. Last previous edition approved in 20082014 asD27
12、82 02 (2008).(2014)1. DOI: 10.1520/D2782-02R14E01.10.1520/D2782-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM we
13、bsite.3 Available from ASTM International Headquarters. Order Adjunct No. ADJD2509. Original adjunct produced in 1972.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may
14、 not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbo
15、r Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2.1 load-carrying capacity of a lubricantas determined by this test method, the maximum load or pressure that can besustained by the lubricant (when used in the given system under specific conditions) without failure of the slid
16、ing contact surfacesas evidenced by scoring or seizure or asperity welding.3.2.2 OK value, nas determined by this test method, the maximum mass (weight) added to the load lever weight pan, at whichno scoring or seizure occurs.3.2.3 score value, nas determined by this test method, the minimum mass (w
17、eight) added to the load lever weight pan, atwhich scoring or seizure occurs.3.2.3.1 DiscussionWhen the lubricant film is substantially maintained, a smooth scar is obtained on the test block, but when there is a breakdownof the lubricant film, scoring or surface failure of the test block takes plac
18、e, as shown in Figs. 1 and 2. In its simplest and mostrecognized form, scoring is characterized by the furrowed appearance of a wide scar on the test block and by excessive pick-upof metal on the surface of the test cup. The form of surface failure more usually encountered, however, consists of a co
19、mparativelysmooth scar, which shows local damage that usually extends beyond the width of the scar. Scratches or striations that occur in anotherwise smooth scar and that do not extend beyond the width of the scar are not considered as evidence of scoring.3.2.4 seizure or asperity weldinglocalized f
20、usion of metal between the rubbing surfaces of the test pieces. Seizure is usuallyindicated by streaks appearing on the surface of the test cup, an increase in friction and wear, or unusual noise and vibration.Throughout this test method the term seizure is understood to mean seizure or asperity wel
21、ding.4. Summary of Test Method4.1 The tester is operated with a steel test cup rotating against a steel test block. The rotating speed is123.71 mmin 6 0.77 mmin (405.88 ftmin 6 2.54 ftmin), which is equivalent to a spindle speed of 800 rmin 6 5 rmin. Fluidsamples are preheated to 37.8 C 6 2.8 C (100
22、 F 6 5 F) before starting the test.4.2 Two determinations are made: the minimum load (score value) that will rupture the lubricant film being tested between therotating cup and the stationary block and cause scoring or seizure; and the maximum load (OK value) at which the rotating cupwill not ruptur
23、e the lubricant film and cause scoring or seizure between the rotating cup and the stationary block.5. Significance and Use5.1 This test method is used widely for the determination of extreme pressure properties for specification purposes. Users arecautioned to carefully consider the precision and b
24、ias statements herein when establishing specification limits.FIG. 1 Test Blocks Showing Various Types of ScarFIG. 2 ScoringD2782 1726. Apparatus6.1 Timken Extreme Pressure Tester,4 described in detail in Annex A1 and illustrated in Fig. 3.6.2 Sample Feed Device,4 for supplying the test specimens wit
25、h fluid is described in Annex A1.6.3 Loading Mechanism,4 for applying and removing the load weights without shock at the uniform rate of0.91 kgs to 1.36 kgs (2 lbs to 3 lbs). A detailed description is given in Annex A1.6.4 Microscope,4 low-power (50 to 60) having sufficient clearance under objective
26、 to accommodate the test block. It shouldbe fitted with a filar micrometer so that the scar width may 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 flammable. Harmful when inhal
27、ed. See A3.1.)7.2 Stoddard Solvent or White Spirit, reagent grade. (WarningFlammable. See A3.2.)4 The sole source of supply of the apparatus known to the committee at this time is Falex Corp., 1020 Airpark Dr., Sugar Grove, IL 60554. If you are aware of alternativesuppliers, please provide this info
28、rmation to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsible technicalcommittee,1 which you may attend.FIG. 3 Timken TesterD2782 1737.3 Test Cup,4,5 of carburized steel, having a Rockwell Hardness “C” Scale Number of 58 to 62, or a Vick
29、ers Hardness Numberof 653 to 756. The cups have a width of 0.514 in. 6 0.002 in., a perimeter of 6.083 in. 6 0.009 in., a diameter of1.938 in. + 0.001 in., 0.005 in. and a maximum radial run-out of 0.0005 in. The axial surface roughness should lie between0.51 m and 0.76 m (20 in. and 30 in.) C.L.A.7
30、.4 Test Blocks,4,6 with test surfaces 0.485 in. 6 0.002 in. wide and 0.750 in. 6 0.016 in. long, of carburized steel, having aRockwell Hardness “C” Scale Number of 58 to 62, or a Vickers Hardness Number of 653 to 756. Each block is supplied with fourground faces and the surface roughness should lie
31、between 0.51 m and 0.76 m (20 in. and 30 in.) C.L.A.8. Preparation of Apparatus8.1 Clean the apparatus with (1) Stoddard solvent or White Spirit, and (2) acetone and blow dry. (WarningExtremelyflammable. Harmful when inhaled. See A3.1.) (WarningFlammable. See A3.2.) Flush with approximately 1 L (1 q
32、t) of the fluidto 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 Stoddard solvent or White Spirit (WarningFlammable. See A3.2.) and drywith a clean soft cloth or paper. Immediately before use
33、rinse the test cup and block with acetone and blow them dry. Do not usesolvents such as carbon tetrachloride or others that may inherently possess load-carrying properties which may effect the results.NOTE 2This cleaning may be done in an ultrasonic cleaner.8.3 Assemble the tester carefully (Fig. 4)
34、, placing the test cup on the spindle and making certain that it is well seated, drawingit up firmly but avoiding possible distortion from excessive tightening (Note 3). Place the test block in the test block holder andadjust the levers so that all the knife edges are in proper alignment. Exercise s
35、pecial care in placing the stirrup of the spring-weight5 Available from Falex Corp., under Part No. F-25061.6 Available from Falex Corp., under Part No. F-25001.FIG. 3 Timken Tester (continued)D2782 174platform assembly (selection of which will depend on the loading device) in the groove of the load
36、-lever arm to avoid prematureshock to the test block when the load is applied. To ensure that the test block, test block holder, and lever arms are properly alignedand seated, coat the test block and test cup with the lubricant to be tested, and rotate the machine slowly for a few revolutions either
37、by hand or by suitable control mechanism. When the parts 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 to check the radial run-out of the cup in situ not exceed 0.025 mm (0.001 in.) totalindicator movement
38、.9. Procedure9.1 Fill the reservoir of the tester to within 76 mm (3 in.) of the top (approximately 3 L or 3 qt) with the fluid to be tested.Preheat the fluid to 37.8 C 6 2.8 C (100 F 6 5 F).NOTE 4The fluid may be heated by the use of an immersion heater located in the tester reservoir or by heating
39、 the fluid prior to filling the reservoir.If an immersion heater is used, localized overheating must be avoided. This may be done by stirring or by circulating prior to the assembly of the leverarm.NOTE 5Fluids having a viscosity above about 5000 cSt (5000 mm2/s) at 40 C often cannot be tested at th
40、e prescribed fluid temperature of 37.8 C6 2.8 C (100 F 6 5 F) because of inability of the pump to recirculate the fluid at this temperature. However, results from limited cooperative tests,covered in Tables A1.1 and A1.2, indicate that the starting fluid temperature could be increased to 65.6 C (150
41、 F) to obtain adequate flow withoutaffecting OK or score values. Testing of such high-viscosity fluids at room temperature in the Test Method D2509 grease feeder also appears valid butmay be difficult because of fluid leakage.9.2 Set the discharge valve at full open. Allow the lubricant to flood the
42、 test cup and block. When the sump is about half filledwith the fluid, start the motor and run for 30 s to break-in. If the equipment used is equipped with acceleration control, start themotor and increase the spindle speed gradually to achieve 800 rmin 6 5 rmin after 15 s. Run for a further 15 s to
43、 complete thebreak-in.9.3 After a break-in period of 30 s, start the timer and apply at 8.9 Ns to 13.3 Ns (2 lbfs to 3 lbfs), a load that is less thanthe expected score load. In the absence of a better estimate, a starting load of 30 lbf is recommended. The load-lever arm,spring-weight platform asse
44、mbly is not considered a part of the applied load. In the event a lower starting load is used, it mustbe a multiple of 6. Then allow the machine to run at 800 rmin 6 5 rmin for 10 min 6 15 s after load application is initiated,unless a score is detected before that period.9.4 If, after the load has
45、been applied, scoring is evident by vibration or noise, stop the tester at once, turn off the flow oflubricant, and remove the load. Since the excessive heat developed with deep scoring may alter the surface characteristics of theentire block, discard the test block. (WarningThe machine and test pie
46、ces may be hot at this point and care should be exercisedin their handling.)9.5 If no scoring is detected, allow the tester to run for 10 min 6 15 s from the start of the application of the load. At the endof the 10 min 6 15 s period, reverse the loading device and remove the load from the lever arm
47、. Turn off the motor, allow thespindle to come to rest, then turn off the flow of fluid. Remove the load lever and inspect the condition of the test block surfaceat 1 magnification. Microscopical observations shall not be used to define when scoring has occurred. The lubricant has failedat the impos
48、ed load if the wear scar indicates any scoring or welding.NOTE 6A microscope may be used to examine the wear scar for further information as required in 9.9.9.6 If no score is observed, turn the test block to expose a new surface of contact and, with a new test cup, repeat the test, asin 9.5, at 10
49、lbf increments until a load that produces a score is 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 to 37.8 C 6 2.8 C (100 F 6 5 F), cool the shaft to less than 65.6 C (150 F),install a new test cup, and turn the test block to expose a new surface of contact. When seizure has occurred, discard the entire test block since excessiveheat, developed when scarring occurs, may alter the surface characteristi
