1、Designation: D 566 02Designation: 132/96An American National StandardBritish Standard 2877Standard Test Method forDropping Point of Lubricating Grease1This standard is issued under the fixed designation D 566; 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 (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1
3、.1 This test method covers the determination of the drop-ping point of lubricating grease.1.2 This test method is not recommended for use at bathtemperatures above 288C. For higher temperatures TestMethod D 2265 should be used.1.3 This standard does not purport to address all of thesafety concerns,
4、if any, associated 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 specific hazardstatements, see 6.4 and 8.1.2. Referenced Documents2.1 ASTM Standard
5、s:D 217 Test Methods for Cone Penetration of LubricatingGrease2D 235 Specification for Mineral Spirits (Petroleum Spirits)(Hydrocarbon Dry Cleaning Solvents)3D 2265 Test Method for Dropping Point of LubricatingGrease Over Wide Temperature Range3E 1 Specification for ASTM Thermometers43. Terminology3
6、.1 Definitions:3.1.1 lubricating grease, na semi-fluid to solid product ofa thickener in a liquid lubricant.3.1.1.1 DiscussionThe dispersion of the thickner forms atwo-phase system and immobilizes the liquid lubricant bysurface tension and other physical forces. Other ingredients arecommonly include
7、d to impart special properties. D 2173.1.2 thickener, nin lubricating grease, a substance com-posed of finely-divided particles dispersed in a liquid to formthe products structure.3.1.2.1 DiscussionThickeners can be fibers (such as vari-ous metallic soaps) or plates or spheres (such as certainnon-so
8、aps thickeners), which are insoluble or, at most, onlyvery slightly soluble in the liquid lubricant. The generalrequirements are that the solid particles are extremely small,uniformly dispersed and capable of forming a relatively stable,gel-like structure with the liquid lubricant. D 2173.2 Definiti
9、ons of Terms Specific to This Standard:3.2.1 dropping point, na numerical value assigned to agrease composition representing the temperature at which thefirst drop of material falls from the test cup; that temperaturebeing the average of the thermometer readings of the sampleand bath.3.2.1.1 Discuss
10、ionIn the normal and proper operation ofthis test method the temperature of the interior of the greasetest cup and the temperature of the oil bath are monitoredsimultaneously as the bath is heated. When the first drop ofmaterial falls from the cup, the temperature of the grease testcup and the bath
11、temperature are averaged and recorded as theresult of the test.4. Summary of Test Method4.1 A sample of lubricating grease contained in a cupsuspended in a test tube is heated in an oil bath at a prescribedrate. The temperature at which material falls from the hole inthe bottom of the cup is average
12、d with the temperature of theoil bath and recorded as the dropping point of the grease.5. Significance and Use5.1 In general, the dropping point is the temperature atwhich the grease passes from a semisolid to a liquid state underthe conditions of test. This change in state is typical of greases1Thi
13、s test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.G0.03 on Physical Tests.Current edition approved April 10, 2002. Published May 2002. Originallypublished as D 566 40 T. Last previous edition D 566 97
14、e1.In the IP, this test method is under the jurisdiction of the StandardizationCommittee. This test method was adopted as a joint ASTM-IP standard in 1964.This test method has been adopted for use by government agencies to replaceMethod 1421 of Federal Test Method Standard No. 791b.2Annual Book of A
15、STM Standards, Vol 05.01.3Annual Book of ASTM Standards, Vol 06.04.4Annual Book of ASTM Standards, Vol 14.03.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.containing as thickeners soaps of conventional types. Greasescontaining as t
16、hickeners materials other than conventionalsoaps can, without change in state, separate oil. This testmethod is useful to assist in identifying the grease as to typeand for establishing and maintaining bench marks for qualitycontrol. The results are considered to have only limitedsignificance with r
17、espect to service performance as droppingpoint is a static test.NOTE 1Cooperative testing indicates that in general, dropping pointsby Test Method D 5665and Test Method D 2265 are in agreement. Incases where results differ, there is no known significance. However,agreement between producer and consu
18、mer as to the test method used isadvisable.6. Apparatus6.1 Grease CupA chromium-plated brass cup conformingto the dimensions shown in Fig. 1.6.2 Test TubeA test tube of heat-resistant glass,6with rim,100 to 103 mm in length and 11.1 to 12.7 mm in insidediameter provided with three indentations about
19、 19 mm fromthe bottom, equally spaced on the circumference. The depth ofthese indentations shall be such as to support the grease cup atabout the point shown in Fig. 2.6.3 Thermometers, two, having ranges as shown below andconforming to the requirements prescribed in SpecificationE1:Thermometer Numb
20、erTemperature Range ASTM IP5 to + 300C 2C 62C6.4 AccessoriesA stirred oil bath consisting of a 400-mLbeaker, a ring stand and ring for support of the oil bath, clampsfor thermometers, two corks as illustrated in Fig. 2, a polishedmetal rod 1.2 to 1.6 mm in diameter and 150 to 152 mm inlength (Fig. 3
21、), a cup plug gage and thermometer depth gage,both shown in Fig. 1.(WarningThe fluid for the oil bathmust have a flash point in excess of the maximum temperatureat which the bath is to be used7and allowance must be madefor thermal expansion to prevent overflow. Heating is prefer-ably done by an imme
22、rsed electrical-resistance heater regulatedby voltage control. An open flame must not be used as theheating source.) (WarningWhen a hot plate is used, caremust be taken to avoid spilling oil on the hot surface.)7. Sampling7.1 When ready to test, examine the sample for any indica-tion of non-homogene
23、ity such as oil separation, phase changes,or gross contamination. When any abnormal conditions arenoted, obtain a new sample.8. Preparation of Apparatus8.1 Thoroughly clean the cup and test tube with mineralspirits conforming to Specification D 235. (WarningFlammable. Vapor harmful.)8.2 Use only cup
24、s that are clean and free from any residuefrom previous runs. When the interior plating of the cup showsindications of wear, discard.8.3 When new cups are to be used, check their dimensionsby using the cup plug gage (Fig. 1). To check the bottomopening a 2.72-mm rod should fit easily while a 2.82-mm
25、 rodshould not.8If the hole is undersized, ream to correct size. Iftoo large, discard.8.4 Test tube shall be clean and free of residues. Inspect thetube for evidence of chipping or cracking, particularly thepoints of indentation. Replace when necessary.5Cooperative data are available from ASTM Inter
26、national by requestingRR:D02-1164.6Borosilicate glass has been found satisfactory for this purpose.7Dow Corning 710 Fluid has been found satisfactory when bath temperatures ashigh as 288C are required. Dow Corning is a registered trademark of the DowCorning Corp., Midland, MI 48686.8These are common
27、ly available as a764-in. drill and a No. 34 drill, respectively.NOTE 1Dimensions in millimetres.FIG. 1 Plug Gage, Depth Gage, and Grease CupD5660228.5 Inspect both cork ring guide and upper cork for charringor distortions in shape. Total clearance between the cork ringguide and the inside wall of th
28、e test tube is 1.5 mm. Wheneither cork is abnormal, replace.8.6 Inspect the bulb end of the thermometer to be used in thetest tube. Clean if there is any residue build-up.9. Procedure9.1 Fill a test cup with sample by pressing the largeropening into the grease to be tested until the cup is filled.Re
29、move excess grease with a spatula. Gently press the cup,held in a vertical position with the smaller opening at thebottom, down over the metal rod until the latter protrudes about25 mm. Press the rod against the cup in such a manner that therod makes contact at both upper and lower peripheries of th
30、ecup. Maintain this contact, rotating the cup on the rod along theindex finger to give a spiral-like motion down the rod toremove a conical section of the grease which adheres along therod.As the cup approaches the end of the rod, carefully slip therod out of the cup so that a smooth film, free of a
31、ir bubbles andof reproducible thickness, remains inside the cup. See Fig. 4.9.2 Place the corks on the thermometer to be used in the testtube as shown in Fig. 2. With the thermometer depth gage inposition in the test tube, adjust the position of the upper cork onthe thermometer so that the thermomet
32、er bulb bottoms snuglyin the depth gage. Observe the relative position of the top edgeof the upper cork to the thermometer stem as well as therelative position of the top edge of the test tube to the cork.Care must be taken to be certain that the thermometer isinserted to the same depth when the app
33、aratus is reassembledwith the grease cup in position.9.3 Replace the depth gage with the grease cup as shown inFig. 2 so that the thermometer is inserted to the previouslygaged depth. When properly inserted, the bulb of the thermom-eter does not touch either the grease sample or the cup.9.4 Suspend
34、the test tube in the oil bath to a depthcorresponding to the 76 mm immersion mark on the thermom-eter. This should leave the test tube rim at least 6 mm above theoil level.9.5 Suspend the second thermometer in the oil bath so thatits bulb is at approximately the same level as the bulb of thetest tub
35、e thermometer.9.6 Stir the oil bath and heat at a rate of 4 to 7C/min untilthe bath reaches a temperature of approximately 17C belowthe expected dropping point of the grease. At this point reducethe rate of heating so that the temperature difference betweenthe test tube and the oil bath is maintaine
36、d between 1 and 2C.This condition is established when the oil bath is heated at arate of about 1 to 1.5C/min. As the temperature increases,material will gradually protrude through the orifice of thegrease cup. When a drop of material falls, note the tempera-tures on the two thermometers and record t
37、heir average to thenearest degree as the dropping point of the grease.NOTE 1Dimensions in millimetres.FIG. 2 Assembled ApparatusNOTE 1Dimensions in millimetres.FIG. 3 Polished Metal RodD566023NOTE 2Certain greases form a drop with a tailing thread uponmelting, which can break off or which can hold u
38、ntil the drop reaches thebottom of the test tube; in any case, the observed dropping point is thetemperature when the drop reaches the bottom of the test tube.NOTE 3The dropping points of some greases, particularly thosecontaining simple aluminum soaps, are known to decrease upon aging, thechange be
39、ing much greater than the deviation permitted in results obtainedby different laboratories. Therefore, comparative tests between laborato-ries should be made within a period of six days.9.7 Two determinations can be made simultaneously in thesame bath, provided both samples have approximately thesam
40、e dropping points.10. Report10.1 Report the result to the nearest degree as the ASTM-IPdropping point, ASTM D566.11. Precision and Bias911.1 PrecisionThe precision of this test method as deter-mined by statistical examination of interlaboratory results is asfollows:11.1.1 RepeatabilityThe difference
41、 between two test re-sults obtained by the same operator with the same apparatusunder constant operating conditions on identical test materialwould, in the long run, in the normal and correct operation ofthe test method, exceed the following value only in one case intwenty:Repeatability 5 7C(1)11.1.
42、2 ReproducibilityThe difference between two singleand independent results obtained by different operators work-ing in different laboratories on identical test material would, inthe long run, in the normal and correct operation of the testmethod, exceed the following value in only one case in twenty:
43、Reproducibility 5 13C(2)NOTE 4Although the cooperative data does show that precisionvaried considerably with dropping point range, a statistical analysis of thecomposite of the cooperative data was used to generate the precisionstatement. This test data is given in the article “Report ofASTM Technic
44、alCommittee G on Dropping Point Methods for Lubricating Grease” by P.R. McCarthy appearing in the NLGI Spokesman, Vol 31, 1967, page 76.11.1.3 BiasThere is no bias in this test method becausethe value of the dropping point can be defined only in terms ofthe test method.12. Keywords12.1 dropping poin
45、t; grease; lubricating grease9There is no research report on file because this test method was developed priorto the development of Research Report guidelines. The statistical method used todetermine precision is unknown.FIG. 4 Procedure to Fill CupD566024ASTM International takes no position respect
46、ing the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This stan
47、dard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM Internatio
48、nal Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.
49、This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D566025
