Long-Term Investigations of Different Bearing Configurations at Solid-Lubricated Rolling Bearings

This paper presents the results of wear and service life investigations of solid-lubricated rolling bearings. The cage of the bearing consists of a PI matrix with 15% MoS2 and serves as a lubrication depot in addition to silver coated balls. First, investigations of the bearing system within the bearing service life are presented, and the torque curve, the wear mass and surface analyses are discussed. With regard to wear, it is shown which that the bearing rings tend to increase in mass over the life of the bearing and while the balls and the cage tend to decrease in mass. With respect to the elemental surface condition, the surfaces of the bearing rings and balls are examined with respect to the mass of the elements on them. Furthermore, service life investigations with different material pairings are presented, whereby the focus here is on the service life achieved, in addition to the torque curve, the wear development and the surface analysis. It could be shown, that MoS2 in the cage results in a longer service life while an Ag coating of the balls has no positive effect on the service life and even seems so reduce it when combined with MoS2.