WEAR CHARACTERISTICS OF LUBRICATING GREASE (FOUR BALL METHOD): ASTM D2266
(Equivalent Test Methods: IP 239, ISO 11008, and DIN 51350)
EXPLANATION
The four ball wear test method can be used to determine the relative wear preventing properties of greases in sliding steel-on-steel applications under specific test conditions. If the test conditions are changed, the relative ratings may be different. The test is not intended to predict wear characteristics with metal combinations other than steel-on-steel. This test method cannot be used to differentiate between extreme pressure and nonextreme pressure greases. No correlation has been established between this test and field service.
TEST SUMMARY
A steel ball is rotated under load against three stationary steel balls having grease lubricated surfaces. The diameters of the wear scars on the stationary balls are measured after completion of the test.
TEST PRECISION
Repeatability: 0.20 mm
Reproducibility: 0.37 mm
There is no bias.
