Modelling and reliability analysis of bearing-shaft interference fit

Interference fit is a common way for joints between bearing and shaft in rotor-bearing system. However, in practical engineering design, the actual interference fit is subject to uncertainties arising from multiple design parameters. To this end, a reliability model of bearing-shaft interference fit considering the influence of centrifugal force is proposed based on the bearing-shaft assembly model combined with the four-order moment method and the reliability sensitivity analysis of variables is conducted. The reliability of rotor-bearing system at different rotational speeds and the sensitivity of reliability to each variable is explored. The accuracy of the bearing-shaft assembly model is verified by comparing the results with the published literature, and the numerical results of the proposed method are compared with those of Monte Carlo simulation (MCS), and the feasibility of the proposed method is demonstrated. It turns out that the reliability model can better quantify the level of tightness of the joint between the bearing and shaft, thereby providing valuable theoretical insights for the structural design of rotor-bearing systems.