1、Designation: D6138 11D6138 13Standard 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 oforigin
2、al adoption 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- preventi
3、ve properties of greases using grease- lubricated ballbearings under dynamic wet conditions.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any,
4、associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D217 Test Methods for Cone Penetration of Lubricating Gr
5、easeD665 Test Method for Rust-Preventing Characteristics of Inhibited Mineral Oil in the Presence of WaterD1193 Specification for Reagent Water2.2 ISO Standards:3ISO 15 Rolling bearings - Radial bearings - Boundary dimensions - General planISO 3696 Water for analytical laboratory use - Specification
6、s and test methodsISO 7120 Petroleum products and lubricants - Petroleum oils and other fluids - Determination of rust-preventing characteristicsin the presence of water3. Terminology3.1 Definitions:3.1.1 lubricating grease, na semifluid to solid product of a thickener in a liquid lubricant.3.1.1.1
7、DiscussionThe dispersion of the thickener forms a two-phase system and immobilizes the liquid lubricant by surface tension and otherphysical forces. Other ingredients are commonly included to impart special properties. D2173.1.2 thickener, nin lubricating grease, a substance composed of finely-divid
8、ed particles dispersed in a liquid lubricant to formthe products structure.3.1.2.1 DiscussionThe thickeners can be fibers (such as various metallic soaps) or plates or spheres (such as certain non-soap thickener), which are1 This test method is under the jurisdiction of ASTM Committee D02 on Petrole
9、um Products and Lubricants and is the direct responsibility of Subcommittee D02.G0.06on Functional Tests - Contamination.Current edition approved May 1, 2011May 1, 2013. Published May 2011 May 2013. Originally approved in 1997. Last previous edition approved in 20072011 asD6138D6138 11.07. DOI: 10.1
10、520/D6138-11.10.1520/D6138-13.2 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 website.3 Available from American Natio
11、nal Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.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 not be technically
12、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.*A Summary of Changes section appears at the end of this standar
13、dCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1insoluble or, at most, only very slightly soluble in the liquid lubricant. The general requirements are that the solid particles beextremely small, uniformly dispersed, and capable of f
14、orming a relatively stable, gel-like structure 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 stain through which the underlying metal surface is still visible shall be ignored.4. Summa
15、ry of Test Method4.1 New, cleaned, and lubricated bearings are tested partially immersed in water (distilled, synthetic sea water, or sodiumchloride solution) under no applied load at a speed of 8365 rpm in a predetermined sequence of running and stopping for a periodof approximately one week. After
16、 cleaning, the bearing rings are examined and rated according to the degree of corrosion.5. Significance and Use5.1 This test method is used to assess the ability of grease to prevent corrosion in rolling bearings operated in the presence ofdistilled water, sodium chloride solution, or synthetic sea
17、 water. It is used for development and specification purposes.6. Apparatus6.1 Test BearingsUse a double row self-aligning ball bearing (30 by 72 by 19 mm), conforming to 1306 K of ISO 15, witha steel cage.4 In cases of dispute, the SKF bearing specified in Footnote 5 shall be used as the referee bea
18、ring.6.2 SKF TMG/Emcor Test Machine, see Annex A1 for description.6.3 Dentists Mirror, non-magnifying.6.4 Graduated Pipette or Syringe, capable of measuring 20 6 1 mL water.6.5 Oven, capable of maintaining 90 6 2C.7. Reagents7.1 Purity of ReagentsReagent grade chemicals shall be used in all tests. U
19、nless otherwise indicated, it is intended that allreagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society, wheresuch specifications are available.5 Other grades may be used, provided it is first ascertained that the reagent is of sufficie
20、ntly highpurity to permit its use without lessening the accuracy of the determination.7.2 Purity of WaterUnless otherwise indicated, references to water shall be understood to mean freshly boiled double distilledwater, water conforming to Specification D1193 Type II, or reagent water as defined by G
21、rade 2 of ISO 3696.7.3 Synthetic Sea WaterIf required, as specified in Specification D665, and ISO 7120.7.4 Sodium Chloride Solutiona 0.5-mol/L solution of sodium chloride prepared using freshly boiled double distilled water,water conforming to Specification D1193 Type II, or water conforming to Gra
22、de 2 of ISO 3696, at a pH of 8.0 to 8.2 adjusted bytitration with sodium hydroxide solution.NOTE 1Other water types, such as that specified in Specification D1193, Type III, or other salt solutions and salt concentrations can be used in thistest method, although the precision when using other water
23、types and salt solutions has not been determined. It is recommended that the pH of the otherwater types is determined before use.7.5 Isopropyl Alcohol(WarningFlammable. Poison. Causes burns. Vapor extremely irritating. May be fatal if swallowed.Harmful if inhaled.)7.6 Ammonium Hydroxide(WarningFlamm
24、able. Poison. Causes burns. Vapor extremely irritating. May be fatal ifswallowed. Harmful if inhaled.)7.7 Solvent Rinse Solution, of the following composition by volume:7.7.1 90 % Isopropyl alcohol.7.7.2 9 % Distilled water.7.7.3 1 % Ammonium hydroxide, 3.2-mol/L concentration. (WarningFlammable. Po
25、ison. Causes burns. Vapor extremelyirritating. May be fatal if swallowed. Harmful if inhaled.)4 1306 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.5 Reagent Chemicals, American Chemical Society Specificatio
26、ns, American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed bythe American Chemical Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeil Convention,
27、Inc. (USPC), Rockville, MD.D6138 1327.8 Mineral Spirit, also known as Stoddard Solvent, reagent grade. (Warning Combustible. Vapor Harmful.)8. Preparation of Bearings8.1 Examine the test bearings carefully and select only bearings that have outer rings and balls entirely free of corrosion. Duringthe
28、 bearing preparation, handle the bearings with tongs or protective gloves. Do not touch the bearings with bare fingers at anytime. Use two new bearings for each grease being tested.8.2 Number bearings on the outside diameter of the outer ring, but do not use chemical etching. One method to number th
29、ebearings is with an electric pen, which should be grounded on the outer ring surface being marked.8.3 Wash the selected bearings thoroughly in hot (50 to 65C) mineral spirits (Warningsee 7.8) to remove the rust preventive.To ensure complete removal, subject the bearing to a second wash in fresh hot
30、 mineral spirits. (WarningThe washingtemperatures specified are considerably above the flash point of the solvent. Accordingly, the washing operation should be carriedout in a well-ventilated hood where no ignition source is present.)8.4 Transfer bearings to the solvent rinse solution (Warningsee 7.
31、7.3) to remove any mineral spirits which may be present.Rinse each bearing and slowly rotate one ring relative to the other ring in fresh hot (65 65C) solvent rinse solution. Fresh rinsesolution is used to avoid the selective evaporation of the components at the rinse temperature.NOTE 2Care must be
32、taken when handling bearings in the hot rinse solution to avoid burns. Tongs and heat resistant gloves are recommended.8.5 Remove each bearing from the solvent rinse solution and place on filter paper to drain. After draining, dry the bearing inan oven at 90 6 2C for 15 to 30 min.8.6 Permit the bear
33、ing to cool to room temperature and reexamine the surfaces to ensure that corrosion-free bearings have beenselected. (Exercise care when handling the bearing to avoid rotating one ring relative to the other ring after cleaning and drying.)8.6.1 Inspect the outer ring tracks. (Fig. 1 illustrates the
34、area to be inspected.) If etch spots or corrosion are evident, reject thebearing. A dentists mirror can be helpful for inspection purposes.9. Procedure9.1 Prepare the apparatus by removing all traces of grease from the previous tests by wiping the plummer blocks. Wash theplummer blocks with the solv
35、ent rinse solution followed by water. Dry thoroughly using a lint-free cloth.9.2 Distribute 10 g 6 0.1 g of the grease evenly in each test bearing using a spatula or bearing packer. Take care to avoid theinclusion of air bubbles. Rotate the outer ring slightly with a gloved hand to assist distributi
36、on. Smear all the external surfaces ofthe bearing with additional grease.9.3 Prepare two bearings for each grease to be tested. Each pair of bearings is used for one test.9.4 Place the adapter sleeves, bearings, and V-ring seals in position on the shaft and finger-tighten the sleeve nuts.9.5 Place t
37、he shaft complete with greased bearings in position in the test rig, taking care that the bearings are centered in theplummer blocks.9.6 Place the top halves of the plummer block in position and finger-tighten the locking screws.9.7 Press the V-ring seals up against the plummer blocks using the spec
38、ial tool supplied with the test machine.9.8 Run the test rig for 30 6 5 min at 83 6 5 rpm immediately after assembly to distribute the grease evenly.9.9 Without delay, remove the top halves of the plummer blocks and introduce 10 mL of distilled water, synthetic sea water orsodium chloride solution i
39、nto each side of each plummer block (a total of 20 6 1 mL) using a pipette or syringe. Refit top halvesof plummer blocks and finger-tighten the locking screws.FIG. 1 Partial Outer Ring of Double-Row Self-Aligning BearingD6138 133NOTE 3Although the test can be run with other user-defined solutions, t
40、he precision limits described in Section 12 apply only to tests conducted withreagents described in Section 7.9.10 Without delay, operate the test rig according to the following schedule:9.10.1 Run 8 h 6 10 min, stop, allow to stand 16 h 6 10 min;9.10.2 Run 8 h 6 10 min, stop, allow to stand 16 h 6
41、10 min;9.10.3 Run 8 h 6 10 min, stop, allow to stand 108 h 6 2 h.9.11 Immediately following the time schedule (9.10), remove the top halves of the plummer blocks. Lift the shaft and bearingson to a suitable support on the work bench. Unscrew the sleeve nuts one or two revolutions. Tap the bearings l
42、ightly to free them,then pull bearings, sleeves, and seals off the shaft.9.12 Dismantle the bearings for inspection by prying balls out of the cage pockets until the outer ring can be removed.9.13 Wash the outer rings in the solvent rinse solution and dry, using a lint-free cloth. Examine immediatel
43、y.10. Rating Procedure10.1 Visually examine the outer ring track area for rust or etch spots, without the aid of any optical adjuncts, and evaluate asdescribed in Table 1. Fig. 1 illustrates the area to be examined. Fig. 2 illustrates examples intended to assist in the assessment ofthe degree of cor
44、rosion. Ignore any staining through which the underlying metal surface is clearly visible.11. Report11.1 Report the degree of corrosion and the type of water solution used for the test in accordance with one of the classificationsand descriptions in Table 1. If the two ratings agree within the preci
45、sion given for repeatability, report the two figures, otherwisemake two further determinations.NOTE 4To assist in estimating percentage corrosion area, a transparent grid divided into suitable squares can be used.12. Precision and Bias12.1 PrecisionThe precision of this test method, as determined by
46、 statistical examination of interlaboratory results, is asfollows:12.1.1 RepeatabilityThe difference between successive test results, obtained by the same operator with the same apparatusunder constant operating conditions on identical test material, in the normal and correct operation of the test m
47、ethod, would exceedthe values shown in Table 2 only in one case in twenty.12.1.2 ReproducibilityThe difference between two single and independent results, obtained by different operators working indifferent laboratories on nominally identical test material, in the normal and correct operation of the
48、 test method, would exceedthe values shown in Table 2 only in one case in twenty.NOTE 5The precision is based on that adopted by the ISO committee from the IP Precision Evaluation Panel reports issued on June 27, 1979 andJanuary 28, 1980, for the IP 220 round robin performed in 1965. A copy of these
49、 reports is available from ASTM Headquarters.612.2 BiasThe procedure for determining the corrosion preventive properties of grease has no bias because the value ofcorrosion is defined only in terms of this test method.6 Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:D02-1417.TABLE 1 Corrosion ClassificationsNOTE 1Under certain circumstances a pair of parallel bands may beobserved, the color of which changes with viewing angle; do not confusethese bands with corrosion w
