1、Designation: D4170 10D4170 16Standard Test Method forFretting Wear Protection by Lubricating Greases1This standard is issued under the fixed designation D4170; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. 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 evaluates the fretting wear protection provided by lubricating greases.1.2 The values stated in SI units are to
3、 be regarded as the standard. Other units are for information only.1.2.1 ExceptionOther units are provided for information only.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish
4、 appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. For specific warning statements, see 7.2 and 9.2.2. Referenced Documents2.1 ASTM Standards:2Test Methods for Rating Motor, Diesel, and Aviation Fuels; Motor Fuels (Section I), Reference Ma
5、terials and BlendingAccessories (Annex 2), Reference Fuels (A2.7.3.3), and Table 32 (Specification for n-Heptane Motor Fuel)2.2 Military Standard:3MIL-S-22473D Sealing, Locking and Retaining Compounds, Single-Component3. Terminology3.1 Definitions:3.1.1 fretting wear, na form of attritive wear cause
6、d by vibratory or oscillatory motion of limited amplitude characterized bythe removal of finely-divided particles from the rubbing surfaces.43.1.1.1 DiscussionAir can cause immediate local oxidation of the wear particles produced by fretting wear. In addition, environmental moisture orhumidity can h
7、ydrate the oxidation product. In the case of ferrous metals, the oxidized wear debris is abrasive iron oxide (Fe2O3)having the appearance of rust, which gives rise to the nearly synonymous terms, fretting corrosion and friction oxidation.Arelated,but somewhat different phenomenon often accompanies f
8、retting wear. False brinelling is localized fretting wear that occurs whenthe rolling elements of a bearing vibrate or oscillate with small amplitude while pressed against the bearing race. The mechanismproceeds in stages: (1) asperities weld, are torn apart, and form wear debris that is subsequentl
9、y oxidized; (2) due to thesmall-amplitude motion, the oxidized detritus cannot readily escape, and being abrasive, the oxidized wear debris accelerates thewear. As a result, wear depressions are formed in the bearing race. These depressions appear similar to the Brinell depressionsobtained with stat
10、ic overloading. Although false brinelling can occur in this test, it is not characterized as such, and instead, it isincluded in the determination of fretting wear.4. Summary of Test Method4.1 The tester is operated with two ball thrust bearings, lubricated with the test grease, oscillated through a
11、n arc of 0.21 rad0.21 rad (12), at a frequency of 30.0 Hz (1800 cpm), under a load of 2450 N (550 lbf), for 22 h at room temperature (Note 1).Fretting wear is determined by measuring the mass loss of the bearing races.1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Pro
12、ducts, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.G0.04 on Functional Tests - Tribology.Current edition approved May 1, 2010Dec. 1, 2016. Published June 2010February 2017. Originally approved in 1982. Last previous edition approved in 20022010 asD417097(2002)D41
13、70 10.1 . DOI: 10.1520/D4170-10.10.1520/D4170-16.2 See 1998 Annual Book of ASTM Standards, Vol 05.04.3 Available from Standardization Documents Order Desk, DODSSP, Bldg. 4, Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098.4 NLGI Lubricating Grease Guide, 3rd edition.This document is not an A
14、STM 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 possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In
15、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 standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1NOTE 1Ar
16、c, frequency, and load are factory-set operating conditions and should not be altered.The load spring constant may change over an extendedtime period. Spring calibration should be checked periodically and, if necessary, a suitable shim should be fabricated to obtain the required load (63 %)at the as
17、sembled length of the spring.5. Significance and Use5.1 This test method is used to evaluate the property of lubricating greases to protect oscillating bearings from fretting wear.This method, used for specification purposes, differentiates among greases allowing low, medium, and high amounts of fre
18、ttingwear under the prescribed test conditions. The test has been used to predict the fretting performance of greases in wheel bearingsof passenger cars shipped long distances.5 Test results do not necessarily correlate with results from other types of service. It isthe responsibility of the user to
19、 determine whether test results correlate with other types of service.6. Apparatus6.1 Falex Fretting Wear Tester, Model F-1581, 6,7 as purchased and illustrated in Figs. 1 and 2.6.2 Spring Guide, conforming to description in Fig. 3, if not supplied with tester.6.3 Test Bearings, 8,7 of the ball thru
20、st type having an inside diameter of 16.0016.00 mm60.025 mm (0.630(0.630 in.60.001in.), an outside diameter of 35.6935.69 mm60.025 mm (1.405 + 0.001 in.), (1.405 in.60.001 in.), and assembled height of 15.756 0.25 mm (0.620 6 0.010 in.) 15.75 mm 6 0.25 mm (0.620 in. 6 0.010 in.) and equipped with ni
21、ne 7.142-mm(0.2812-in.)7.142 mm (0.281 in.) diameter balls in a pressed steel retainer; all surfaces (except retainer) to be ground. Differentsurface finishes are provided on commercial bearings. Bearings with ground surfaces are lustrous; tumbled bearings appear slightlydulled or grayish. Bearings
22、with ground races, as specified in 6.3, are required to obtain correct results. Tumbled bearings withreground races are satisfactory. Magnification should be used to inspect the races to verify that they have been ground. Part-numberbearings8,7 are provided with ground races. A drawing of the test b
23、earing, giving complete, detailed dimensions and specificationsis available in RR:D02-1159.96.4 Vibration Mount, 10,7 upon which the tester is placed.6.5 Time Switch, (optional) shown in Fig. 1 and described in detail in Fig. 4, or a commercial equivalent.6.6 Ultrasonic Cleaner. 11,76.7 Analytical B
24、alance having a capacity of about 100 g and with a minimum sensitivity of 0.1 mg.5 Verdura, T. M., “Development of a Standard Test to Evaluate Fretting Protection Quality of Lubricating Grease,” NLGI Spokesman, Vol XLVII, No. 5, August 1983, pp.15767.6 Falex Fretting Wear Tester, formerly known as t
25、he Fafnir Friction Oxidation Tester, is available from Falex Corp., 1020 Airpark Dr., Sugar Grove, IL 60554.7 The sole source of supply of the apparatus known to the committee at this time is listed. If you are aware of alternative suppliers, please provide this information toASTMHeadquarters. Your
26、comments will receive careful consideration at a meeting of the responsible technical committee,1 which you may attend.8 Andrews (Part No. 06X65) have been found to be satisfactory. Prepared bearings (part number F-1581-50 (formerly FL-1081), that is, with set screw flat (see 8.1), areavailable from
27、 Falex Corp., 1020 Airpark Dr., Sugar Grove, IL 60554.9 Supporting data (the results of the cooperative test program, from which these values have been derived) have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D02-1159.10 Isomode Vibration contro
28、l Pad No. 3451801 has been found satisfactory and is available from rubber products suppliers.11 ABransonic 2200 cleaner (Branson Ultrasonics Co., Danbury, CT 06813) having a capacity of about 3 L(34 gal) operating at a frequency of about 55 kHz, with a powerinput of about 125 W, has been found sati
29、sfactory.FIG. 1 Fafnir Friction Oxidation Tester and Time SwitchD4170 1627. Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allreagents shall conform to the specifications of the Committee on Analytical R
30、eagents of the American Chemical Society wheresuch specifications are available.12 Other grades may be used, provided it is first ascertained that the reagent is of sufficiently highpurity to permit its use without lessening the accuracy of the determination.7.2 n-heptane, reagent grade or ASTM Moto
31、r Fuel Grade 3. (WarningFlammable. Health hazard.)NOTE 2This test method was originally developed using chloroform, which was subsequently replaced by 1,1,1-trichloroethane because of its lowertoxicity. Since then, 1,1,1-trichloroethane was declared an Ozone Depleting Substance by the U.S. Environme
32、ntal Protection Agency (EPA). Federalregulations ban the production of this material after December 31, 1995, but existing stocks may continue to be used. Currently there are no EPArestrictions on the use of chloroform, but the user should be aware of its health hazards if it is used as a functional
33、ly equivalent solvent. No other solventintended as a substitute for 1.1.1-trichloroethane1,1,1-trichloroethane in this test method has been cooperatively evaluated. However, it is the experienceof the Grease Subcommittee that elimination of the cleaning step using 1,1,1trichloroethane does not affec
34、t the reported results from this test.12 Reagent Chemicals, American Chemical Society Specifications, 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, Dors
35、et, U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.FIG. 2 Chuck and Housing AssemblyFIG. 3 Spring GuideD4170 1638. Bearing Preparation8.1 Grind a suitable set screw flat (approximate dimensions; 88 mm by 44 mm by 0.5 mm) on t
36、he periphery of each bearingrace;8 flat must be square with face to prevent cocking of races when set screws are tightened.NOTE 3It is extremely difficult to grind the flat square with the face when using a hand or bench grinder. Good results have been obtained by rackinga number of bearing races in
37、 a V-block and using a surface grinder.8.2 Scribe suitable identification marks on the outer lands of bearing races to distinguish races of upper bearing from races oflower bearing. Identification marks should not be scribed on back or periphery of the bearing race.8.3 Fill tank of ultrasonic cleane
38、r with distilled water to a depth of 3030 mm to 40 mm. Place two bearing sets in a250-mL250 mL beaker containing about 125-mL125 mL of n-heptane. Cover beaker and place in ultrasonic bath. After cleaningfor 1010 min to 15 min, 15 min, transfer bearing parts to second beaker containing 125 mL 125 mL
39、of n-heptane (see 7.2). Cleanfor 88 min to 10 min, then repeat operation for two additional 44 min to 5-min5 min washes, using new n-heptane and cleanbeakers each time.8.4 Place bearing parts onto freshly cleaned, glass Petri dishes or aluminum moisture dishes to air dry. Bearings should bepropped a
40、gainst rim of dish to permit air circulation. Clean bearings must not be rotated or air blown. Do not place bearings onany surface other than freshly cleaned glass or metal. Do not touch bearings with bare hands; use forceps or tongs, or wearsurgeonsurgical gloves or finger cots.8.5 When bearings ar
41、e dry, place dishes containing bearings in a desiccator and let stand for a minimum of 30 min.8.6 Weigh the upper and lower bearing race pairs separately to the nearest 0.1 mg. (Each race pair consists of two races.)9. Procedure9.1 In a dust-free environment, install the test grease in unused, clean
42、ed, weighed bearings.9.1.1 Fill the ball tracks of the bearing races with the test grease. Use a suitable spatula to strike the grease level with the bearinglands. Bearing backs and bearing seats must be kept free of grease and particulate matter. Clean with a lintfree cloth slightlymoistened with n
43、-heptane.9.1.2 Fill each ball retainer with test grease taking care to fill all the cavities around the balls on both sides of the retainer.Remove excess grease from the bore and rim of the retainer, but leave an excess of grease on the cupped side. Adjust the massof the grease in each bearing to 1.
44、01.0 g 6 0.05 g.9.2 Assemble the chuck.Asuggested procedure for chuck assembly is described in 9.2.1 9.2.7. Use Fig. 5 as a guide to chuckassembly. Use minimal force when tightening set screws. Locate bearing set screw flats normal to set screws. Purpose of set screwsis to prevent rotation of races
45、in seats. To preclude overtightening set screws, grasp hex-key (Allen wrench) by shank rather thanby lever arm. If set screws tend to loosen during the test, use a low-strength anaerobic sealant (MIL-S-22473D, Grade H or similar)on the threads rather than more force. Bearing races must bottom on bea
46、ring seats. Bottoming can be verified by visual and tactileinspection. (WarningTight set screws, misalignment between set screws and flats, or set screw flats that are not square with thebearing face can cock the bearing upon tightening set screws, causing uneven wear. Loose set screws combined with
47、 oily or greasybearing backs and seats could allow a poor grease to give erroneous test results because of race creep effects.)FIG. 4 Time Switch CircuitD4170 1649.2.1 Preassemble upper bearing races and bearing retainer with the flats aligned and the cupped side of the bearing retainerpositioned so
48、 it will face upward during assembly (downward during operation).9.2.2 Install an upper bearing race preassembly in the chuck top and tighten the set screw,top, ensuring that the flats are alignedwith the set screw and the bearing race is bottomed on the bearing seat. Tighten the race set screw usin
49、g minimal force.9.2.3 Invert the chuck top and secure in a bench vise.9.2.3 Place the retainer of the upper bearing on the race in the chuck top (9.2). The cupped side must be positioned upwardduring assembly (downward during operation).9.2.4 Install the other race of the upper bearing in the oscillating bearing seat. oscillating bearing seat on the shaft such that theupper bearing components are properly aligned and mated. Using minimal force, tighten the set screw. (With all bearing set screwsoriented alike, permanently mark the underside of the oscillating
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