ASTM D2783 - Measurement of Extreme-Pressure Properties of Lubricating Fluids (Four-Ball Method)
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 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.Extracted, with permission, from ASTM D2783-19 - 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