Dynamic modeling and reliability analysis of the ball bearing rotating accuracy considering the uncertain bearing-shaft interference fit

Abstract

The rotating accuracy of the rolling bearing is closely related to its precision class and the actual fitting parameters. However, there are few quantitative evaluation models to describe their relationships. In this paper, considering the effect of the uncertain but bounded interference amounts between the bearing inner ring and the shaft, the Chebyshev interval analysis method is utilized and a rotating accuracy dynamic reliability model is presented based on the two degrees of freedom (2-DOF) rotor-ball bearing system. Firstly, the relationships between the bearing radial clearance and bearing-shaft interference amounts are investigated based on the shaft-bearing interference fit model. Thus, in terms of Chebyshev interval analysis method, the 2-DOF rotor-ball bearing system with uncertain bearing-shaft interference amounts is established. Then the rotating accuracy dynamic reliability model of the ball bearing is presented based on the Chebyshev interval theory. The effects of the average values and deviation coefficients of the initial interference amounts on the actual interference amounts, radial clearance and the resultant rotating accuracy dynamic reliability of the ball bearing are analyzed. The results show that the uncertain bearing-shaft interference amounts have a significant effect on the rotating accuracy dynamic reliability of the ball bearing and reasonable design could improve the rotating accuracy of the ball bearing. The results calculated by the present study are compared to the Monte Carlo simulation (MCS), which show the validity of the study.