ASTM D2783 - Four Ball EP
Significance and Use
5.1 This test method, used for specification purposes, differentiates between lubricating fluids having low, medium, and high level of extreme-pressure properties. The user of this method should determine to his own satisfaction whether results of this test procedure correlate with field performance or other bench test machines.
1.1 This test method covers the determination of the load-carrying properties of lubricating fluids. The following two determinations 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 of lubricating greases, see Test Method D2596.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
Extracted, with permission, from ASTM D2783 - 03(2014) Standard Test Method for Measurement of Extreme-Pressure Properties of Lubricating Fluids (Four-Ball Method), copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be purchased from ASTM International, astm.org