Analysis of dynamic characteristics of cylindrical roller bearing cage based on a thermomechanical coupling model

Rolling bearings often operate under elevated temperatures during service, which can substantially influence the dynamic behavior of the cage, thereby reducing both the operational precision and service life of the bearing. However, most existing analytical models for cage dynamics are established under the assumption of a uniform and constant temperature field, neglecting the coupled thermal–mechanical effects. This simplification leads to discrepancies between the theoretical predictions and the actual operating conditions. This article develops a real-time thermomechanical coupling model specifically for cylindrical roller bearings. This model integrates a transient thermal network model with the dynamic model corresponding to the bearing system, comprehensively accounting for the dynamic interactions among bearing components, the hydrodynamic effects of the lubricant, interfacial friction, thermal expansion of structural elements, and the temperature-dependent variations in lubricant properties. Through this coupled modeling framework, the temperature rise behavior of the cage, along with the thermal influences on its motion stability and vibration characteristics, is systematically investigated. The results indicate that the cage temperature increases rapidly during the initial stage of operation and gradually approaches a thermally stable state. The final steady-state temperature exhibits a nonlinear growth with both rotational speed and radial load. Thermal effects enhance the motion stability of the cage to some extent but markedly intensify its vibration amplitude. These findings offer valuable theoretical insights for optimizing cage design and enhancing the thermodynamic performance and reliability of rolling bearings.