Characterization of Microscopic Damage Evolution of Functional Groove in Cageless Bearings

Abstract

Bearings with partial function grooves as cageless bearings related to magnetic floating bearing protection have characteristics, such as fast offsetting of the impact force caused by rotor fall, and they gradually become important parts of ultra clean and cryogenic transportation systems. However, the functional failure mechanism of the bearing, which is caused by functional groove wear, is not clear. Therefore, this paper establishes a force–motion intrinsic model of particles inside the functional groove, which is based on the discrete element method, which it itself combined with the functional groove damage evolution trend analysis. Then, a hyper-quadratic surface model of inter-particle contact is established to simulate the time-varying friction coefficient of the functional groove by combining particles of different sizes to form particle clusters. Additionally, as the boundary condition, EDEM is used to solve the contact motion state of rolling element rolling through the functional groove for one week to obtain the overlap between particles and contact force change law. The results show that the wide side of the functional groove wears more seriously than the narrow side, and the rolling element leaves the functional groove with more impact than when it enters the functional groove, and the functional groove wears more seriously. In this paper, through the study of local functional groove wear of cageless ball bearing, we propose to characterize the damage extension of functional groove by using the number of particle fracture and motion trend in discrete element method, and this study provides theoretical guidance for the design of cageless bearings.