ASTMD2783-2003

Designation:D 2783-03An American Nafional StandardNTERNATIONALStandard 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 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.Scope1.1 This test method covers the determination of the load-carrying properties of lubricating fluids.The following twodetemminations 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 D 2596.1.3 This standard does not purport to address all of theHERTZ LINEsafety concerns,if any,associated with its use.It is theAPPLIED LOAD,KGresponsibility of the user of this standard to establish appro-ABE-Compensation line.priate safety and health practices and determine the applica-B-Point of last nonseizure load.bility of regulatory limitations prior to use.BC-Region of incipient seizure.1.4 The values stated in either inch-pound units or SI unitsCD-Region of immediate seizure.D-Weld point.are to be regarded separately as standard.Within the text,theFIG.1 Schematic Plot of Scar Diameter Versus Applied LoadSI units are shown in brackets.The values stated in each systemare not exact equivalents;therefore,each system shall be usedindependently of the other.Combining values from the two3.1.1.1 Discussion-Coordinates for the compensation linesystems may result in nonconfommance with the standard.are found in Table 1,Columns 1 and 3.2.Referenced Documents3.1.1.2 DiscussionSome lubricants give coordinateswhich are above the compensation line.Known examples of2.1 ASTM Standards:such fluids are methyl phenyl silicone,chlorinated methylD 2596 Test Method for Measurement of Extreme-PressureProperties of Lubricating Grease (Four-Ball Method)2phenyl silicone,silphenylene,phenyl ether,and some mixturesof petroleum oil and chlorinated paraffins.2.2 ANSI Standard:B 3.12 Metal Balls33.1.2 compensation scar diameter-the average diameter,inmillimetres,of the wear scar on the stationary balls caused by3.Terminologythe rotating ball under an applied load in the presence of a3.1 Definitions:lubricant,but without causing either seizure or welding.3.1.2.1 Discussion-The wear scar obtained shall be within3.1.1 compensation line-a line of plot on logarithmicpaper,as shown in Fig.1,where the coordinates are scar5%of the values noted in Table 1,Column 3.3.1.3 corrected load-the load in kilograms-force (or new-diameter in millimetres and applied load in kilograms-force(ortons)for each run obtained by multiplying the applied load bynewtons),obtained under dynamic conditions.the ratio of the Hertz sca