1、Designation: D 6138 07An American National StandardStandard Test Method forDetermination of Corrosion-Preventive Properties ofLubricating Greases Under Dynamic Wet Conditions (EmcorTest)1This standard is issued under the fixed designation D 6138; the number immediately following the designation indi
2、cates the 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers the determinatio
3、n of corrosion-preventive properties of greases using grease- lubricated ballbearings under dynamic wet conditions.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 thesafe
4、ty concerns, 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.2. Referenced Documents2.1 ASTM Standards:2D 217 Test Methods for Cone Pene
5、tration of LubricatingGreaseD 665 Test Method for Rust-Preventing Characteristics ofInhibited Mineral Oil in the Presence of WaterD 1193 Specification for Reagent Water2.2 ISO Standards:3ISO 15 Rolling bearings - Radial bearings - Boundarydimensions - General planISO 3696 Water for analytical labora
6、tory use - Specifica-tions and test 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 li
7、quid lubricant.3.1.1.1 DiscussionThe 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. D 2173.1.2 thickener, nin lubricating grease, a substance co
8、m-posed of finely-divided particles dispersed 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
9、 liquid lubricant. The general require-ments are that the solid particles be extremely small, uniformlydispersed, and capable of forming a relatively stable, gel-likestructure with the liquid lubricant. D 2173.2 Definitions of Terms Specific to This Standard:3.2.1 corrosion, nred rust or black spots
10、 on the race.3.2.1.1 Discussionany 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 applie
11、d load at a speed of83 6 5 rpm in a predetermined sequence of running and1This 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 edition approved July 1
12、, 2007. Published August 2007. Originallyapproved in 1997. Last previous edition approved in 2003 as D 613803.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the st
13、andards 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 International, 100 Barr Harbor Drive, PO B
14、ox C700, West Conshohocken, PA 19428-2959, United States.stopping for a period of approximately one week. Aftercleaning, 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 corrosio
15、n in rolling bearings 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
16、steel cage.4In cases 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 main
17、taining 90 6 2C.7. 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
18、available.5Other 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 defi
19、nedby Grade 2 of ISO 3696.7.3 Synthetic Sea WaterIf required, as specified in Speci-fication D 665, 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
20、solution.NOTE 1Other water types, such as that specified in SpecificationD 1193, 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
21、(WarningFlammable. 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 com
22、position byvolume:7.7.1 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, reage
23、ntgrade. (WarningCombustible. 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 beari
24、ngs withbare fingers 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
25、.3 Wash the selected 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 t
26、he solvent. Accordingly, 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 ringrela
27、tive to the other ring 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 r
28、ecommended.8.5 Remove 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 sel
29、ected. (Exercise care 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 helpfu
30、l for inspectionpurposes.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 grea
31、se evenly in each testbearing 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 , AmericanC
32、hemical Society, Washington, 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), Ro
33、ckville,MD.D6138072the 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 th
34、e adapter sleeves, 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 pos
35、itionand finger-tighten 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 halve
36、s of the plummerblocks 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 r
37、un with other user-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
38、10 min, stop, allow 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 t
39、wo revolutions. Tap 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 lin
40、t-free cloth. Examine 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 thea
41、ssessment of the degree 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 ra
42、tingsagree within 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 t
43、est method, as deter-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 corr
44、ect operation of the 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
45、and correct operation 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 performe
46、d in 1965. Acopy of 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 Hea
47、dquarters and maybe 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 confuse
48、these bands with corrosion 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
49、 of corrosion covering 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 surfaceD613807313. 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)
