1、Designation: D 2509 03Designation: 326/83 (88)An American National StandardStandard Test Method forMeasurement of Load-Carrying Capacity of LubricatingGrease (Timken Method)1This standard is issued under the fixed designation D 2509; the number immediately following the designation indicates the yea
2、r 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope *1.1 This test method covers the determination of the loa
3、d-carrying capacity of lubricating greases by means of theTimken Extreme Pressure Tester.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, assoc
4、iated 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. For specificwarning statements, see 7.1, 7.2, and 9.4.2. Referenced Documents2.1 ASTM Adjuncts:ADJD2
5、509, Glossy Prints of Test Blocks Showing VariousTypes of Scar23. Terminology3.1 Definitions:3.1.1 load-carrying capacity, of a lubricating grease,nthe maximum load or pressure that can be sustained by alubricating grease without failure of the sliding contact sur-faces as evidenced by seizure or we
6、lding.3.1.1.1 DiscussionThe values of load carrying capacity ofa lubricating grease vary according to test method.3.1.2 scoring, in tribology, na severe form of wearcharacterized by the formation of extensive grooves andscratches in the direction of sliding.3.1.2.1 DiscussionWhen the lubricant film
7、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 Fig. 1.2In its simplest and recognized form, scoring is characterized bya wide scar on the test block and b
8、y the transfer of metal fromthe test block to the contacting surface of the test cup. The formof surface failure more usually encountered, however, consistsof a comparatively smooth scar, which shows local damagethat usually extends beyond the width of the scar. Scratches orstriations that occur in
9、an otherwise smooth scar and that do notextend beyond the width of the scar are not considered scoringin this test method.3.1.3 seizure or welding, nlocalized fusion of rubbingmetal, usually indicated by streaks of transferred metal, in-creased friction and wear, or unusual noise and vibration.3.1.4
10、 wear, nthe removal of metal from a rubbing surfaceby mechanical action, or by a combination of mechanical andchemical actions.3.2 Definitions of Terms Specific to This Standard:3.2.1 OK value, nthe maximum mass (weight) added tothe load lever mass (weight) pan, at which no scoring orseizure occurs.
11、3.2.2 score value, nthe minimum mass (weight) added tothe load lever mass (weight) pan, at which scoring or seizureoccurs.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) whic
12、h is equivalent to a spindlespeed of 800 6 5 rpm. Grease samples are brought to andapplied at 24 6 6C (75 6 10F).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 abrasion;and th
13、e maximum load (OK value) at which the rotating cup1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.G0 on Lubricating Grease.Current edition approved May 10, 2003. Published May 2003. Originallya
14、pproved in 1966. Last previous edition approved in 1998 as D 250993(1998).This test method was adopted as an ASTM-IP Standard.2Available from ASTM International Headquarters. Order Adjunct No.ADJD2509.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 10
15、0 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.will not rupture the lubricant film and cause abrasion betweenthe rotating cup and the stationary block.5. Significance and Use5.1 The test method is used widely for specification pur-poses and is used to differentiate
16、 between greases having low,medium, or high levels of extreme pressure characteristics. Theresults may not correlate with results from service.6. Apparatus and Materials6.1 Timken Extreme Pressure Tester, described in detail inAnnex A1 and illustrated in Fig. 2.6.2 Sample Feed Devices, for supplying
17、 the test specimenswith grease are described in Annex A1.6.3 Loading Mechanism, for applying and removing theload mass (weight) without shock at the uniform rate 0.91 to1.36 kg/s (2 to 3 lb/s). A detailed description is given in AnnexA1.6.4 Test Cups,3,4of carburized steel, having a RockwellHardness
18、 C Scale Number of 58 to 62, or a Vickers HardnessNumber of 653 to 746. The cups have a width of 13.06 6 0.05mm (0.514 6 0.002 in.), a perimeter of 154.51 6 0.23 mm(6.083 6 0.009 in.), a diameter of 49.22 +0.025, 0.127 mm(1.938 +0.001, 0.005 in.), and a maximum radial run-out of0.013 mm (0.0005 in.)
19、. The axial surface roughness should liebetween 0.51 and 0.76 m (20 and 30 in.) C.L.A.6.5 Test Blocks4,5with test surfaces 12.32 6 0.10 mm(0.485 6 0.004 in.) wide and 19.05 6 0.41 mm (0.750 6 0.016in.) long, of carburized steel, having a Rockwell Hardness CScale Number of 58 to 62, or a Vickers Hard
20、ness Number of653 to 746. Each block is supplied with four ground faces andthe surface roughness should lie between 0.51 and 0.76 m (20and 30 in.) C.L.A.6.6 Microscope,4,6low-power (503 to 603), having suffi-cient clearance under objective to accommodate the test block.It should be fitted with a fil
21、ar micrometer so that the scar widthmay be measured with an accuracy of 60.05 mm (60.002 in.).6.7 Timer, graduated in minutes and seconds.7. Reagents7.1 Acetone, reagent grade, minimum purity. (WarningExtremely flammable. Vapors can cause flash fire.)7.2 Stoddard Solvent, also known as Mineral Spiri
22、ts, reagentgrade. (WarningCombustible. Vapor harmful.)8. Preparation of Apparatus8.1 Clean the apparatus with Stoddard solvent and acetone(see 7.1 and 7.2), and blow dry. Shield the sump outlet anddisconnect the oil pump to eliminate wear on the unused pump.Replace the oil reservoir with the grease
23、feed device.3The sole source of supply of the test cups known to the committee at this timeis Falex Corp. 1020 Airpark Dr., Sugar Grove, IL 60554 under Part No. F-25061.4If you are aware of alternative suppliers, please provide this information toASTM International Headquarters. Your comments will r
24、eceive careful consider-ation at a meeting of the responsible technical committee1, which you may attend.5The sole source of supply of the test blocks known to the committee at this timeis Falex Corp. 1020 Airpark Dr., Sugar Grove, IL 60554 under Part No. F-25001.6Falex Corp. is a satisfactory sourc
25、e of supply.FIG. 1 Test Blocks Showing Various Types of ScarD25090328.2 Select a new test cup and block, wash with Stoddardsolvent, and dry with a clean soft cloth or paper. Immediatelybefore use rinse the test cup and block with acetone and blowthem dry. Do not use solvents such as carbon tetrachlo
26、ride orothers that may inherently possess load-carrying propertieswhich may affect the results.8.3 Assemble the tester carefully (Fig. 3), 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
27、 1). Place the test block in the testblock 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 a
28、void premature shock to the test block whenthe load is applied. To ensure the test block, test block holder,and lever arms are properly aligned and seated, coat the testblock and test cup with the grease to be tested, and rotate themachine slowly for a few revolutions either by hand or bysuitable co
29、ntrol mechanism. If the parts are in alignment, thegrease will be wiped off the cup over its entire width.NOTE 1At this point it is recommended that a dial indicator be usedto check that the radial run-out of the cup in situ does not exceed 0.001 in.(0.025 mm) total indicator movement.9. Procedure9.
30、1 Bring the grease to 24 6 6C (75 6 10F). Fill thegrease-feeding device with grease, avoiding the inclusion of airbubbles. Apply a film of grease to the test cup and block andthoroughly grease the guide bushing with the test grease. Donot heat the grease.9.2 Apply the grease at 25 6 6C (75 6 10F) to
31、 the testblock through the grease-feed mechanism at the uniform rate of45 6 9 g/min (0.1 6 0.02 lb/min). Start the motor and run for30 s to break-in. If the equipment used is equipped withacceleration control, start the motor and increase the spindlespeed gradually to achieve 800 6 5 rpm after 15 s.
32、 Run for afurther 15 s to complete the break-in.9.3 After the break-in period of 30 s, start the timer andapply at 8.9 to 13.3 N/s (2 to 3 lbf/s), a load of 133.4 N (30 lbf).(A starting load of 133.4 N (30 lbf/s) is recommended. Theload lever arm, spring, and mass (weight) carrier assembly areFIG. 2
33、 Timken TesterD2509033not considered part of the applied load.) Then allow themachine to run at 800 6 5 rpm for 10 min 6 15 s after loadapplication is initiated, unless a score is detected before thatperiod. Excessive noise and fluctuations in the spindle speedindicate scoring of the test components
34、. Stop the machine atonce, turn off the supply of grease lubricant, and remove theload.9.4 If, after the load has been applied, scoring is evident byvibration or noise, stop the tester at once, remove the load, andturn off the flow of lubricant. Since the excessive heatdeveloped with deep scoring ma
35、y 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 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 t
36、he load. At theend of the 10 min 6 15 s period, reverse the loading device andremove the load from the lever arm. Turn off the motor, allowthe spindle to come to rest, then turn off the flow of grease.Remove the load lever and inspect the condition of the testFIG. 2 (continued)FIG. 3 Assembly of Tes
37、ter Showing Test PiecesD2509034block surface. The lubricant has failed at the imposed load ifthe wear scar indicates any scoring or welding.NOTE 2Microscopical observations should not be used to define ifscoring has occurred, but a skilled operator may use a microscope toexamine the wear scar for fu
38、rther information.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 testwith a load 44.5-N (10-lbf) heavier and in successive testsincrease it in 44.5-N (10-lbf) increments until a load thatproduces a score is reached. At this poi
39、nt decrease the load by22.2 N (5 lbf) for the final determination.9.7 If a score is produced at the 133.4-N (30-lbf) load,reduce the load by 26.7-N (6-lbf) decrements until no scoringis realized. At this point, increase the load by 13.3 N (3 lbf) forthe final determination.9.8 When the wear scar evi
40、dence 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 for this load. Similarly, if the second testproduces no scoring, record a no score rating. If the second testagain yields a que
41、stionable result, simply withhold judgment ofthe rating at this load stage and test the grease at theimmediately next higher and lower load stages. Then assign arating to the load stage in question which is identical to therating obtained at the immediately next higher load stageemployed (see Annex
42、A2).NOTE 3Two other procedures that may be conducted with thisapparatus are described by Appendix X1 and Appendix X2.10. Calculation and Report10.1 Report the OK and score values in terms of the masses(weights) placed on the mass (weight) pan hanging from theend of the load-lever arm; do not include
43、 the mass (weight) ofthe pan assembly. Report the values in multiples of 2.27 kg (5lb) above 13.71 kg (30 lb) and in multiples of 1.36 kg (3 lb)below 30 lb.10.2 When desired, the contact (unit) pressure which existsbetween the cup and block at the conclusion of the test may becalculated.7After the O
44、K value has been determined, removethe test block and wash with Stoddard solvent, rinse withacetone, and blow dry. By means of a filar micrometermicroscope, measure the width of the scars on those blockswhich successfully carried this load. Make all measurements to0.05 mm (0.002 in.) Calculate the c
45、ontact pressure, C,asfollows:C, psi 5 LX 1 G!#/YZ or 20X 1 G!#/Z (1)C, MPa 5 9.81 LX8 1 0.454G!#/Y8Z8 (2)where:L = 10 = mechanical advantage of load-lever arm,G = load-lever constant (value is stamped on lever arm ofeach tester),X = mass (weight) placed on the weight pan, lbX8 = mass (weight) placed
46、 on the weight pan, kg,Y = length of test scar (1/2 in.),Y8 = length of test scar (12.7 mm),Z = average width of test scar, in., andZ8 = average width of test scar, mm.11. Precision and Bias11.1 The precision of this test is not known to have beenobtained in accordance with currently accepted guidel
47、ines (forexample, Research Report RR:D02-1007).811.2 The following criteria should be used for judging theacceptability of OK load results (95 % confidence):11.2.1 RepeatabilityDuplicate results by the same opera-tor should be considered suspect if they differ by more than23 % of their mean. Table X
48、3.1, based on this level ofrepeatability, and the use of the load increments specified in themethod, may be used to quickly check the acceptability of theresults by the same operator.11.2.2 ReproducibilityThe results submitted by each oftwo laboratories should be considered suspect if they differ by
49、more than 59 % of their mean. Table X3.2, based on this levelof reproducibility and the use of the load increments specifiedin the method, may be used to quickly check the acceptabilityof two results, each from a different laboratory.11.3 BiasThe procedure in Test Method D 2509 for mea-suring load-carrying properties of lubricating grease has nobias because the value of load-carrying properties can bedefined only in terms of a test method.NOTE 4These precision data were derived from tests by 14 laborato-ries on five greases whose average Timken OK lo
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