Loading path optimization of shaft clinching forming assembly using finite element simulation and response surface methodology

Shaft clinching forming assembly has become a mainstream clamping technology of wheel bearings. The radial deformation of inner rings is the main negative impact in the shaft clinching forming process. The elastoplastic finite element method was used to study the shaft clinching forming process of wheel bearings, and the accuracy of the numerical simulation was verified by experiment. The ratio of the inner ring outside diameter variation to the clamping force (RIC) was taken as an optimization objective. Response surface methodology was used to optimize the loading path of punches in the shaft clinching forming process. Three factors were selected, including the central angle between two successively appeared outermost points of the plum blossom shape loading trajectory (θ), the rotation speed of the punch (ω), and the tilted angle of punches (α). The results show that the central angle θ is the most sensitive factor, and the interaction effects of the central angle θ and the speed of autorotation ω on the ratio RIC are the most significant. Finally, the minimum ratio RIC and a corresponding loading path are obtained. The research results can be applied to other rotary forging processes.