A review of calculation and analysis methods of friction torques and power losses of rolling element bearings

Rolling element bearings (REBs) are widely used in various rotational mechanical systems. In actual applications, the friction torques and power losses of REBs will greatly affect the performance and life of rotational mechanical systems. A study of the friction torque of REBs can be helpful for improving the rotational mechanical systems’ fatigue life. This work presented a comprehensive review of calculation and analysis methods of friction torques and power losses of REBs. The previous works are divided into three main categories: experimental methods, theoretical methods, and data-driven methods. The experimental and theoretical methods for healthy bearings and unhealthy bearings with surface errors are reviewed in this work. The main ideas of these methods are presented. This work conducted a specific and explicit summary of the applicability and limitations of existing research and provided an outlook on the future works, which can serve as a reference for scholars and engineers when they conduct research on the bearing friction torque.