Measuring Film Thickness in Starved Grease-Lubricated Ball Bearings: An Improved Electrical Capacitance Method

Abstract

Presented in this article is a new method to measure the film thickness in a rolling bearing running under starved conditions, such as in grease-lubricated bearings, using the electrical capacitance method. The method was used to study the impact of speed on film thickness. Results show that fully flooded conditions prevail at lower speeds where the film thickness increases with increasing speed. At higher speeds, where grease-lubricated bearings run under starved lubrication conditions, this increase is less pronounced. At even higher speeds, the film thickness becomes almost independent of the speed.