1、Designation:D742108 Designation: D7421 11Standard Test Method forDetermining Extreme Pressure Properties of LubricatingOils Using High-Frequency, Linear-Oscillation (SRV) TestMachine1This standard is issued under the fixed designation D7421; the number immediately following the designation indicates
2、 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 () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers a procedure for determ
3、ining extreme pressure properties of lubricating oils for hydraulics, gears andengines under high-frequency linear-oscillation motion using the SRV test machine.NOTE 1This test method was developed and the international round robin tests were jointly performed with the DIN 51834 working group. Thisp
4、rocedure is based on the 2005 revision of Test Method D5706 for greases and differs regarding the stroke length and the cleaning solvent.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
5、 address all of the safety concerns, if any, 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:2A295/A295M
6、Specification for High-Carbon Anti-Friction Bearing SteelD235 Specification for Mineral Spirits (Petroleum Spirits) (Hydrocarbon Dry Cleaning Solvent)D4175 Terminology Relating to Petroleum, Petroleum Products, and LubricantsD5706 Test Method for Determining Extreme Pressure Properties of Lubricatin
7、g Greases Using a High-Frequency,Linear-Oscillation (SRV) Test MachineD6425 Test Method for Measuring Friction and Wear Properties of Extreme Pressure (EP) Lubricating Oils Using SRV TestMachineE45 Test Methods for Determining the Inclusion Content of SteelG40 Terminology Relating to Wear and Erosio
8、n2.2 DIN Standards:3DIN 51631:1999 Mineral spirits; special boiling point spirits; requirementsDIN EN ISO 683-17 Heat-treated Steels, alloy steels and free-cutting steels Part 17 : Ball and roller bearing steels (ReplacesDIN 17230-1980)DIN EN ISO 13565-2:1998 Geometrical Product Specifications (GPS)
9、 Surface texture: Profile method; Surfaces havingstratified functional properties Part 2: Height characterization using linear material ratio curve Replacement of DIN4776:1990: Measurement of surface roughness; parameters RK,RPK,RVK,Mr1,Mr2for the description of the material portion2.3 ISO Standards
10、:ISO 1250:1972Mineral solvents for paints, white spirits and related hydrocarbon solvents3. Terminology3.1 Definitions:3.1.1 break-in, nin tribology, an initial transition process occurring in newly established wearing contacts, often accompanied1This test method is under the jurisdiction of ASTM Co
11、mmittee D02 on Petroleum Products and Lubricants and is the direct responsibility of Subcommittee D02.L0 onIndustrial Lubricants.Current edition approved Feb. 1, 2008. Published March 2008. DOI: 10.1520/D7421-08.on Industrial Lubricants and Engineering Sciences of High Performance Fluidsand Solids.C
12、urrent edition approved Dec. 1, 2011. Published March 2012. Originally approved in 2008. Last previous edition approved in 2008 as D742108. DOI:10.1520/D7421-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book
13、of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3Available from Beuth Verlag GmbH (DIN, Deutsches Institut fur Normung e.V.), Burggrafenstrasse 6, 10787, Berlin, Germany, http:/www.en.din.de.1This document is not an ASTM standard and is intended
14、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 all cases only the current ve
15、rsionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.by transients in coefficient of fric
16、tion or wear rate, or both, which are uncharacteristic of the given tribological systems long-termbehavior. G403.1.2 coeffcient of friction, orf,nin tribology, the dimensionless ratio of the friction force (F) between two bodies to thenormal force (N) pressing these bodies together. G403.1.3 Hertzia
17、n contact area, napparent area of contact between two nonconforming solid bodies pressed against each other,as calculated from Hertzs equations of elastic deformation published in 1881. G403.1.4 Hertzian contact pressure, nmagnitude of the pressure at any specified location in a Hertzian contact are
18、a, as calculatedfrom Hertzs equations of elastic deformation. The Hertzian contact pressure can also be calculated and reported as maximumvalue Pmaxin the centre of the contact or as Paverageas average over the total contact area. G403.1.5 lubricant, nany material interposed between two surfaces tha
19、t reduces the friction or wear, or both between them.D41753.1.6 Ra (C.L.A.), nin measuring surface finish, the arithmetic average of the absolute distances of all profile points from themean line for a given distance. Amstutz43.1.6.1 DiscussionC.L.A. means center line average, and it is the synonym
20、to Ra.3.1.7 Rpk, nReduced peak height according to DIN EN ISO 13565-2:1998. Rpk is the mean height of the peak sticking outabove the core profile section.3.1.8 Rvk, nReduced valley height according to DIN EN ISO 13565-2:1998. Rvk is the mean depth of the valley reachinginto the material below the co
21、re profile section.3.1.9 Ry, nin measuring surface finish, the vertical distance between the top of the highest peak and the bottom of the deepestvalley in one sampling length. Amstutz53.1.10Rz (DIN), nin measuring surface finish, the average of all Ry values (peak to valley heights) in the assessme
22、nt length.Amstutz43.2 Definitions of Terms Specific to This Standard:3.2.1 extreme pressure, adjin lubrication, characterized by metal surfaces in contact under high-stress rubbing conditions. Itis not limited to metallic materials.3.2.2 seizure, nlocalized fusion of metal or other materials between
23、 the rubbing surfaces of the test pieces. D57063.2.2.1 DiscussionIn this test method, seizure is indicated by a sharp rise in the coefficient of friction, over steady state, of0.2 for over 20 s. In severe cases, a stoppage in the motor will occur. (These criteria were believed to be right, because t
24、his testmethod is related to liquid lubricants.)3.2.33.3 Abbreviations:3.3.1 SRV, nSchwingung, Reibung, Verschlei (German); oscillating, friction, wear (English translation).4. Summary of Test Method4.1 This test method is performed on an SRV test machine using a steel test ball oscillating against
25、a stationary steel test diskwith lubricant between them. Test load is increased in 100-N increments until seizure occurs. The load, immediately prior to theload at which seizure occurs, is measured and reported as O.K.-load, which can be converted in Hertzian contact pressures.NOTE 2Test frequency,
26、stroke length, temperature, and ball and disk material can be varied to simulate field conditions. The test ball yieldspoint-contact geometry. To obtain line or area contact, test pieces of differing configurations can be substituted for the test balls.NOTE 3With regard to the test chamber and the o
27、perating conditions, SRV models III and IV are identical. However, the SRV IV allows to inclinethe axis of movement. Both models are fully computer controlled. In SRV IV models, the test described here is run horizontally and without inclination.SRV I and II models can also perform this test, but th
28、ey are limited with regard to maximum load and stroke. As modern and high performance oils mayexceed an O.K.-load of 1200 N, seizure may not be reached. Optimol Instruments supplies an upgrade kit to allow for SRV I and SRV II models to beoperated at 1600 N, if needed.55. Significance and Use5.1 Thi
29、s laboratory test method can be used to quickly determine extreme pressure properties of lubricating oils at selectedtemperatures specified for use in applications where not only high-speed vibrational or start-stop motions are present with highHertzian point contact. This test method has found wide
30、 application in qualifying lubricating oils used in constant velocity jointsof front-wheel-drive automobiles, gear-hydraulic circuit, rear axles, gears and engine components. Users of this test method shoulddetermine whether results correlate with field performance or other applications.6. Apparatus
31、6.1 SRV Test Machine,5illustrated in Figs. 1-3.4Available from International Organization for Standardization (ISO), 1 rue de Varemb, Case postale 56, CH-1211, Geneva 20, Switzerland, http:/www.iso.ch.4Amstutz, Hu, “Surface Texture: The Parameters,” Bulletin MI-TP-003-0785, Sheffield Measurement Div
32、ision, Warner and Swasey, 1985.5Amstutz, Hu, “Surface Texture: The Parameters,” Bulletin MI-TP-003-0785, Sheffield Measurement Division, Warner and Swasey, 1985.5The sole source of supply of the apparatus known to the committee at this time is Optimol Instruments GmbH, Westendstr. 125, D-80339 Munic
33、h, Germany. If you areaware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend.D7421 1126.2 Test Balls,552100 steel, 60 6 2 Rc hardness
34、, 0.025 6 0.005-m Ra surface finish, 10-mm diameter.6.3 Lower Test Disk,5vacuum arc remelted (VAR) AISI 52100 steel with a inclusion rating using Method D, Type A, and aseverity level number of 0.5 according to Specification A295/A295M or Test Methods E45 or an inclusion sum value K1 # 10in accordan
35、ce with DIN EN ISO 683-17 and spherodized annealed to obtain globular carbide, 60 6 2 Rc hardness, with thesurfaces of the disk being lapped and free of lapping raw materials. The topography of the disk will be determined by four values,24-mm diameter by 7.85 mm thick:FIG. 1 SRV Test Machine (Model
36、III)FIG. 2 SRV Test Machine (Model IV)D7421 1130.5 m Rz 0.650 m0.035 m C.L.A. (Ra) 0.050 m0.020 m Rpk 0.035 m0.050 m Rvk 0.075 m7. Reagents and Materials7.1 Cleaning Solventsingle boiling point spirit type 2-A according to DIN 51631:1999or ISO 1250:1972. (WarningFlammable. Health hazard.)NOTE 4In th
37、e case of unavailability, please refer to Specification D235 regarding Type I, Class B, mineral spirits.8. Preparation of ApparatusPreparation of SRV I and II models8.1 Turn on the test machine and chart recorder and allow to warm up for 15 min prior to running tests.8.2 Select the friction data to
38、be presented in the crest peak value position in accordance with the manufacturers directions.NOTE 5In most cases, this is accomplished by positioning the sliding switch on electronic card NO. 291.35.20E (front side of electronics behind thefront panel) and the sliding switch located back on the pan
39、el of the control unit.8.3 Turn the amplitude knob to ZERO.8.4 Switch the stroke adjustment to AUTO position.8.5 Set the frequency to 50 Hz.8.6 Set the desired span and calibrate the chart recorder in accordance with the manufacturers instructions. Select the desiredchart speed.8.7 Turn on the heate
40、r control, and preheat the disk holder to the desired temperature. 50C, 80C, and 120C are recommended(see Table 1). When the temperature has stabilized, turn on the chart recorder and depress the drive start toggle switch until thetimer begins to count and then adjust the stroke amplitude knob to 2.
41、00 mm.8.8 Set the load charge amplifier to setting that corresponds to the 400-N load.8.9 Change the load charge amplifier at each load in accordance with the manufacturers instructions when the coefficient offriction at each test load is to be studied.1. Oscillation drive rod 6. Electrical Resistan
42、ce Thermometer2. Test Ball Holder 7. Resistance Thermometer3. Load Rod 8. Test Disk Holder4. Test Ball 9. Piezoelectric Measuring Device5. Test Disk 10. Receiving BlockFIG. 3 Test Chamber ElementsD7421 114TABLE1PrecisionDataNOTE1Extremepressurepassloadsofoilswithoutoutliers(=10mmBall;Stroke=1or2mm;1
43、00Nloadincrementevery2min;y=50Hz,dataper15.10.2006;SRVI,SRVII,SRVIII,andSRVIVmodels).NOTE2TherepeatabilityandthereproducibilitywerecalculatedusingtheASTMsoftware(ADJD6300D2PP).Valuesinparenthesesrepresentaninitial,average(mean)Hertziancontactpressureusingthemeantestloadandtheinitialtestgeometryatthe
44、beginningofthetest.DINE518345/ASTMD7421OilISRVOilISRVOilISRVOilISRVOilIIHLP46OilIIHLP46OilIIHLP46OilIIHLP46OilIII5W-30OilIII5W-30OilIII5W-30OilIII5W-30Test-T80C80C120C120C80C80C120C120C80C80C120C120CStroke,mm121212121212NumberofResults305230543046304630483054DegreeofFreedom172816331727192917361636Hi
45、ghesettestload(N)mean(MPa)890 (3006)1129(3255)890 (3006)1013 (3139)790 (2889)1521 (3598)873 (2987)1477 (3567)1146(3270)1223 (3342)970 (3093)1092 (3218)StandardDeviation632261866335617262506217625662176275620362936150Reproducibility,R9615401006494747629758629821584880430Repeatability,r422185352247325
46、292426334339410306250D7421 1158.10 When the digital timer reaches 30 s, increase the load to 100 N using the slow ramp speed rate, and maintain this load for15 min.8.11 The 15-min interval includes the loading ramp sequence. The load has to be increase by 100 N every 2 min using the slowramp until a
47、 load of 1200 N is reached, or the load limit of the test apparatus is attained, or failure occurs. Failure is indicated bya rise in coefficient of friction of greater than 0.2 over steady state for over 20 s or a stoppage in the oscillating of the test machine(see Test Method D5706or D6425.NOTE 6Be
48、cause a 30-s break-in at 50 N is used, the load increase times will occur on the half minute of even minutes.8.12 When the 1200-N load run or maximum load of the test apparatus is completed or failure occurs, turn off the heater control,release the load to minimum setting, (typically 13 or 14 N), an
49、d remove the test ball, disk, and lubricating oil test specimen.Preparation of SRV III and IV models8.13 When using SRV III and SRV IV models, clean and install the specimens as specified under 9.1 to 9.7. Turn on the testmachine or the PC and allow to warm up for 15 min prior to running tests. The test parameters (Frequency = 50 Hz, testtemperature, stroke = 2 mm) are to be entered via the control software. The test will be run automatically. Test results (coefficientof friction, normal load, total, lin
