Variation of zero entraining velocity dimple in grease-lubricated reciprocating motion

Abstract

In this study, experiments were conducted on a ball-on-disk test rig using optical interferometry to explore the variation in grease film thickness under zero entraining velocity reciprocating motion. The steel ball and the sapphire disk move at equal speeds but in opposite directions within a triangle wave. Three types of commercially available bearing greases with different consistencies, Centoplex 2EP, Centoplex 3, and MP-3, were used in these experiments. The variations in the surface dimple phenomenon with decreasing maximum surface velocity, differing grease consistency, and grease starvation conditions were studied. Results showed that the grease consistency exerts a significant influence on the surface dimple and the starvation severity.