1、Designation: D6138 11Standard Test Method forDetermination of Corrosion-Preventive Properties ofLubricating Greases Under Dynamic Wet Conditions (EmcorTest)1This standard is issued under the fixed designation D6138; the number immediately following the designation indicates the year oforiginal adopt
2、ion 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. Scope*1.1 This test method covers the determination of corrosion-preventive proper
3、ties of greases using grease- lubricated ballbearings under dynamic wet conditions.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated w
4、ith 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.2. Referenced Documents2.1 ASTM Standards:2D217 Test Methods for Cone Penetration of LubricatingGreaseD665 T
5、est Method for Rust-Preventing Characteristics ofInhibited Mineral Oil in the Presence of WaterD1193 Specification for Reagent Water2.2 ISO Standards:3ISO 15 Rolling bearings - Radial bearings - Boundarydimensions - General planISO 3696 Water for analytical laboratory use - Specifica-tions and test
6、methodsISO 7120 Petroleum products and lubricants - Petroleumoils and other fluids - Determination of rust-preventingcharacteristics in the presence of water3. Terminology3.1 Definitions:3.1.1 lubricating grease, na semifluid to solid product ofa thickener in a liquid lubricant.3.1.1.1 DiscussionThe
7、 dispersion of the thickener forms atwo-phase system and immobilizes the liquid lubricant bysurface tension and other physical forces. Other ingredients arecommonly included to impart special properties. D2173.1.2 thickener, nin lubricating grease, a substance com-posed of finely-divided particles d
8、ispersed in a liquid lubricantto form the products structure.3.1.2.1 DiscussionThe thickeners can be fibers (such asvarious metallic soaps) or plates or spheres (such as certainnon-soap thickener), which are insoluble or, at most, only veryslightly soluble in the liquid lubricant. The general requir
9、e-ments are that the solid particles be extremely small, uniformlydispersed, and capable of forming a relatively stable, gel-likestructure with the liquid lubricant. D2173.2 Definitions of Terms Specific to This Standard:3.2.1 corrosion, nreddish rust or black spots on the race.3.2.1.1 Discussionany
10、 stain through which the underlyingmetal surface is still visible shall be ignored.4. Summary of Test Method4.1 New, cleaned, and lubricated bearings are tested par-tially immersed in water (distilled, synthetic sea water, orsodium chloride solution) under no applied load at a speed of83 6 5 rpm in
11、a predetermined sequence of running andstopping for a period of approximately one week. After1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.G0.06 on Functional Tests - Contamination.Current edi
12、tion approved May 1, 2011. Published May 2011. Originallyapproved in 1997. Last previous edition approved in 2007 as D613807. DOI:10.1520/D6138-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandard
13、s volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM Inter
14、national, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.cleaning, the bearing rings are examined and rated according tothe degree of corrosion.5. Significance and Use5.1 This test method is used to assess the ability of grease toprevent corrosion in rolling bear
15、ings operated in the presenceof distilled water, sodium chloride solution, or synthetic seawater. It is used for development and specification purposes.6. Apparatus6.1 Test BearingsUse a double row self-aligning ballbearing (30 by 72 by 19 mm), conforming to 1306 K ofISO 15, with a steel cage.4In ca
16、ses of dispute, the SKF bearingspecified in Footnote 5 shall be used as the referee bearing.6.2 SKF TMG/Emcor Test Machine, see Annex A1 fordescription.6.3 Dentists Mirror, non-magnifying.6.4 Graduated Pipette or Syringe, capable of measuring 206 1 mL water.6.5 Oven, capable of maintaining 90 6 2C.7
17、. Reagents7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.5Other
18、grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.7.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean reagent water as definedby Grade 2 of
19、ISO 3696.7.3 Synthetic Sea WaterIf required, as specified in Speci-fication D665, and ISO 7120.7.4 Sodium Chloride Solutiona 0.5-mol/L solution ofsodium chloride prepared using water conforming to Grade 2of ISO 3696, at a pH of 8.0 to 8.2 adjusted by titration withsodium hydroxide solution.NOTE 1Oth
20、er water types, such as that specified in SpecificationD1193, Type III, can be used in this test method, although the precisionwhen using other water types has not been determined. It is recommendedthat the pH of the other water types is determined before use.7.5 Isopropyl Alcohol(WarningFlammable.
21、Poison.Causes burns. Vapor extremely irritating. May be fatal ifswallowed. Harmful if inhaled.)7.6 Ammonium Hydroxide(WarningFlammable. Poi-son. Causes burns. Vapor extremely irritating. May be fatal ifswallowed. Harmful if inhaled.)7.7 Solvent Rinse Solution, of the following composition byvolume:7
22、.7.1 90 % Isopropyl alcohol.7.7.2 9 % Distilled water.7.7.3 1 % Ammonium hydroxide, 3.2-mol/L concentration.(WarningFlammable. Poison. Causes burns. Vapor ex-tremely irritating. May be fatal if swallowed. Harmful ifinhaled.)7.8 Mineral Spirit, also known as Stoddard Solvent, reagentgrade. (WarningCo
23、mbustible. Vapor Harmful.)8. Preparation of Bearings8.1 Examine the test bearings carefully and select onlybearings that have outer rings and balls entirely free ofcorrosion. During the bearing preparation, handle the bearingswith tongs or protective gloves. Do not touch the bearings withbare finger
24、s at any time. Use two new bearings for each greasebeing tested.8.2 Number bearings on the outside diameter of the outerring, but do not use chemical etching. One method to numberthe bearings is with an electric pen, which should be groundedon the outer ring surface being marked.8.3 Wash the selecte
25、d bearings thoroughly in hot (50 to65C) mineral spirits (Warningsee 7.8) to remove the rustpreventive. To ensure complete removal, subject the bearing toa second wash in fresh hot mineral spirits. (WarningThewashing temperatures specified are considerably above theflash point of the solvent. Accordi
26、ngly, the washing operationshould be carried out in a well-ventilated hood where noignition source is present.)8.4 Transfer bearings to the solvent rinse solution(Warningsee 7.7.3) to remove any mineral spirits whichmay be present. Rinse each bearing and slowly rotate one ringrelative to the other r
27、ing in fresh hot (65 65C) solvent rinsesolution. Fresh rinse solution is used to avoid the selectiveevaporation of the components at the rinse temperature.NOTE 2Care must be taken when handling bearings in the hot rinsesolution to avoid burns. Tongs and heat resistant gloves are recommended.8.5 Remo
28、ve each bearing from the solvent rinse solutionand place on filter paper to drain. After draining, dry thebearing in an oven at 90 6 2C for 15 to 30 min.8.6 Permit the bearing to cool to room temperature andreexamine the surfaces to ensure that corrosion-free bearingshave been selected. (Exercise ca
29、re when handling the bearingto avoid rotating one ring relative to the other ring aftercleaning and drying.)8.6.1 Inspect the outer ring tracks. (Fig. 1 illustrates the areato be inspected.) If etch spots or corrosion are evident, rejectthe bearing. A dentists mirror can be helpful for inspectionpur
30、poses.9. Procedure9.1 Prepare the apparatus by removing all traces of greasefrom the previous tests by wiping the plummer blocks. Washthe plummer blocks with the solvent rinse solution followed bywater. Dry thoroughly using a lint-free cloth.9.2 Distribute 10 g 6 0.1 g of the grease evenly in each t
31、estbearing using a spatula or bearing packer. Take care to avoid41306 K steel caged bearing manufactured by NTN and DKF may be used;however, precision had only been evaluated using SKF 1306 K/236 725 bearings.5Reagent Chemicals, American Chemical Society Specifications , AmericanChemical Society, Wa
32、shington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeil Convention, Inc. (USPC), Rockville,MD.D6138 11
33、2the inclusion of air bubbles. Rotate the outer ring slightly witha gloved hand to assist distribution. Smear all the externalsurfaces of the bearing with additional grease.9.3 Prepare two bearings for each grease to be tested. Eachpair of bearings is used for one test.9.4 Place the adapter sleeves,
34、 bearings, and V-ring seals inposition on the shaft and finger-tighten the sleeve nuts.9.5 Place the shaft complete with greased bearings inposition in the test rig, taking care that the bearings arecentered in the plummer blocks.9.6 Place the top halves of the plummer block in positionand finger-ti
35、ghten the locking screws.9.7 Press the V-ring seals up against the plummer blocksusing the special tool supplied with the test machine.9.8 Run the test rig for 30 6 5 min at 83 6 5 rpmimmediately after assembly to distribute the grease evenly.9.9 Without delay, remove the top halves of the plummerbl
36、ocks and introduce 10 mL of distilled water, synthetic seawater or sodium chloride solution into each side of eachplummer block (a total of 20 6 1 mL) using a pipette orsyringe. Refit top halves of plummer blocks and finger-tightenthe locking screws.NOTE 3Although the test can be run with other user
37、-defined solutions,the precision limits described in Section 12 apply only to tests conductedwith reagents described in Section 7.9.10 Without delay, operate the test rig according to thefollowing schedule:9.10.1 Run 8 h 6 10 min, stop, allow to stand 16 h 6 10min;9.10.2 Run 8 h 6 10 min, stop, allo
38、w to stand 16 h 6 10min;9.10.3 Run 8 h 6 10 min, stop, allow to stand 108 h 6 2h.9.11 Immediately following the time schedule (9.10), re-move the top halves of the plummer blocks. Lift the shaft andbearings on to a suitable support on the work bench. Unscrewthe sleeve nuts one or two revolutions. Ta
39、p the bearings lightlyto free them, then pull bearings, sleeves, and seals off the shaft.9.12 Dismantle the bearings for inspection by prying ballsout of the cage pockets until the outer ring can be removed.9.13 Wash the outer rings in the solvent rinse solution anddry, using a lint-free cloth. Exam
40、ine immediately.10. Rating Procedure10.1 Visually examine the outer ring track area for rust oretch spots, without the aid of any optical adjuncts, and evaluateas described in Table 1. Fig. 1 illustrates the area to beexamined. Fig. 2 illustrates examples intended to assist in theassessment of the d
41、egree of corrosion. Ignore any stainingthrough which the underlying metal surface is clearly visible.11. Report11.1 Report the degree of corrosion and the type of watersolution used for the test in accordance with one of theclassifications and descriptions in Table 1. If the two ratingsagree within
42、the precision given for repeatability, report thetwo figures, otherwise make two further determinations.NOTE 4To assist in estimating percentage corrosion area, a transpar-ent grid divided into suitable squares can be used.12. Precision and Bias12.1 PrecisionThe precision of this test method, as det
43、er-mined by statistical examination of interlaboratory results, is asfollows:12.1.1 RepeatabilityThe difference between successivetest results, obtained by the same operator with the sameapparatus under constant operating conditions on identical testmaterial, in the normal and correct operation of t
44、he testmethod, would exceed the values shown in Table 2 only in onecase in twenty.12.1.2 ReproducibilityThe difference between two singleand independent results, obtained by different operators work-ing in different laboratories on nominally identical test mate-rial, in the normal and correct operat
45、ion of the test method,would exceed the values shown in Table 2 only in one case intwenty.NOTE 5The precision is based on that adopted by the ISO committeefrom the IP Precision Evaluation Panel reports issued on June 27, 1979and January 28, 1980, for the IP 220 round robin performed in 1965. Acopy o
46、f these reports is available from ASTM Headquarters.612.2 BiasThe procedure for determining the corrosionpreventive properties of grease has no bias because the value ofcorrosion is defined only in terms of this test method.6Supporting data have been filed at ASTM International Headquarters and mayb
47、e obtained by requesting Research Report RR:D02-1417.FIG. 1 Partial Outer Ring of Double-Row Self-Aligning BearingTABLE 1 Corrosion ClassificationsNOTEUnder certain circumstances a pair of parallel bands may beobserved, the color of which changes with viewing angle; do not confusethese bands with co
48、rrosion which appears black when viewed from allangles.Rating Designation Description0 no corrosion no corrosion1 trace no more than three spots of corrosion,none of which has a diameter largerthan1mm2 light small areas of corrosion covering up to1 % of the surface3 moderate areas of corrosion cover
49、ing between 1and 5 % of the surface4 heavy areas of corrosion covering between 5and 10 % of the surface5 severe areas of corrosion covering more than10 % of the surfaceD6138 11313. Keywords13.1 corrosion; Emcor test; lubricating grease; rustANNEX(Mandatory Information)A1. APPARATUSA1.1 Dynamic Antirust Test RigsFig. A1.1 shows part ofa standard rig (Drawing No. SKF 1516600) which is capable ofaccommodating up to eight self-aligning ball bearings fittedwith adapter sleeves and sleeve nuts (3) of polyamide plastic.The bearings (2) are located in
