Skidding in deep groove ball bearings

Abstract

This thesis focuses on the investigation of skidding behaviour in a single-row deep groove ball bearing when subjected to radial loads, utilizing various bearing dynamics models. This type of bearing serves as a support component in electric machines, including traction motors. The radial load from the motor shaft generates significant normal and frictional forces between the inner and outer races, the rolling elements, and the cage. The dynamic interplay among these components, influenced by friction and contact forces, leads to skidding in the bearing. This research examines the impact of radial load on both bearing skidding and the dynamics of the cage. To achieve this, mathematical equations that calculate the contact and friction forces acting on the rolling elements and the cage/race, along with dynamic equilibrium equations for both the cage and the rolling elements, as developed by various researchers, have been employed. The study also emphasizes the distinctions arising from these different methodologies. Furthermore, the dynamics of the cage are analysed by graphing the contact forces, orbital velocities, and slip velocities of both the cage and rolling elements over time.