1、Designation:D278303(Reapproved 2014)Standard Test Method forMeasurement of Extreme-Pressure Properties of LubricatingFluids(Four-Ball Method)1This standard is issued under the fixed designation D2783;the number immediately following the designation indicates the year oforiginal adoption or,in the ca
2、se 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.Scope1.1 This test method covers the determination of the load-carrying properties of lubricating fluids.
3、The following twodeterminations are made:1.1.1 Load-wear index(formerly Mean-Hertz load).1.1.2 Weld point by means of the four-ball extreme-pressure(EP)tester.1.2 For the determination of the load-carrying properties oflubricating greases,see Test Method D2596.1.3 This standard does not purport to a
4、ddress all of thesafety 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.1.4 The values stated in SI units are to be regarded as t
5、hestandard.The values given in parentheses are for informationonly.2.Referenced Documents2.1 ASTM Standards:2D2596 Test Method for Measurement of Extreme-PressureProperties of Lubricating Grease(Four-Ball Method)2.2 ANSI Standard:B 3.12 Metal Balls33.Terminology3.1 Definitions:3.1.1 compensation lin
6、ea line of plot on logarithmicpaper,as shown in Fig.1,where the coordinates are scardiameter in millimetres and applied load in kilograms-force(ornewtons),obtained under dynamic conditions.3.1.1.1 DiscussionCoordinates for the compensation lineare found in Table 1,Columns 1 and 3.3.1.1.2 DiscussionS
7、ome lubricants give coordinateswhich are above the compensation line.Known examples ofsuch fluids are methyl phenyl silicone,chlorinated methylphenyl silicone,silphenylene,phenyl ether,and some mixturesof petroleum oil and chlorinated paraffins.3.1.2 compensation scar diameterthe average diameter,in
8、millimetres,of the wear scar on the stationary balls caused bythe rotating ball under an applied load in the presence of alubricant,but without causing either seizure or welding.3.1.2.1 DiscussionThe wear scar obtained shall be within5%of the values noted in Table 1,Column 3.3.1.3 corrected loadthe
9、load in kilograms-force(or new-tons)for each run obtained by multiplying the applied load bythe ratio of the Hertz scar diameter to the measured scardiameter at that load.3.1.4 Hertz linea line of plot on logarithmic paper,asshown in Fig.1,where the coordinates are scar diameter inmillimetres and ap
10、plied load in kilograms-force(or newtons),obtained under static conditions.3.1.5 Hertz scar diameterthe average diameter,inmillimetres,of an indentation caused by the deformation of theballs under static load(prior to test).It may be calculated fromthe equationDh5 8.7331022P!1/3(1)where:Dh=Hertz dia
11、meter of the contact area,andP=the static applied load.3.1.6 immediate seizure regionthat region of the scar-loadcurve characterized by seizure or welding at the startup or bylarge wear scars.Initial deflection of indicating pen on theoptional friction-measuring device is larger than with nonsei-zur
12、e loads.See Fig.1.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.L0.11 on Tribiological Properties of Industrial Fluids andLubricates.Current edition approved Dec.1,2014.Published
13、February 2015.Originallyapproved in 1969.Last previous edition approved in 2009 as D2783 03(2009)1.This method was prepared under the joint sponsorship of the American Societyof Lubrication Engineers.Accepted by ASLE January 1969.DOI:10.1520/D2783-03R14.2For referenced ASTM standards,visit the ASTM
14、website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards 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.Copyright
15、ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.1.7 incipient seizure or initial seizure regionthat regionat which,with an applied load,there is a momentary break-down of the lubricating film.This breakdown is noted by asudden increase in the mea
16、sured scar diameter and a momen-tary deflection of the indicating pen of the optional friction-measuring device.See Fig.1.3.1.8 last nonseizure loadthe last load at which themeasured scar diameter is not more than 5%above thecompensation line at the load.See Fig.1.3.1.9 load-wear index(or the load-carrying property of alubricant),nan index of the ability of a lubricant to minimizewear at applied loads.3.1.9.1 DiscussionUnder the conditions of this test,spe-cific loadings in kilograms-force(or Ne
