Dynamic modeling and vibration characteristic analysis of compound fault of deep groove ball bearing considering the time-varying displacement

This article takes 6306 deep groove ball bearing as the research object, considering the influence of time-varying displacement caused by variable stiffness vibration of rolling bearing on vibration response characteristics. Firstly, the bearing roller is reduced to a nonlinear spring-damping structure based on Hertzian contact theory, and a dynamic model of the rolling bearing is created. Second, the coupling solution of the motion controlling equation is found using the Runge-Kutta approach. Finally, numerical simulation is used to examine the vibration characteristics of bearings under single fault of the rolling element and outer ring and compound fault of the rolling element and outer ring, respectively. The observed signal attests to the model's correctness that was developed in this research. The modeling signal and the experimental vibration signal agree well. In the meantime, the spectrum diagram makes the defect characteristic frequency and its frequency doubling signal quite evident. The results show that the model may be used to analyze and forecast the vibration of a deep groove ball bearing with a fault, and they also provide a theoretical framework for studying the vibration response of a compound fault involving both the rolling element and the outer raceway.