Experimental and numerical study of the effect of raceway waviness on the oil film in thrust ball bearings

Using a custom-made optical interferometer, the waviness values on the raceway of the washer of two thrust ball bearings are obtained by applying the Hertzian contact theory. The experimental system can also simulate elastohydrodynamic lubrication (EHL) in the thrust ball bearings, so the variations of oil film over one revolution of the bearing are measured. Based on the experimental parameters, EHL calculations are carried out to reproduce the contacts between the balls and the glass, especially those between the balls and the raceway. The experimental and theoretical results show that the variation of the oil film in the thrust ball bearing is closely related to the raceway waviness.