FEM-Based Study on Interference Fits in High-Speed Rotatory Spindles

Spindle is a key unit of the high-speed machine tool,while the interference fit between spindle and motor rotor is one of the most important factors influencing the performance of the spindle unit. The existing of centrifugal force may cause the variation of the interference fit very greatly. Especially when the rotating speed is high,the influence is very distinct,and become the major factor affecting the performances of the interference fit. By using the elastic-plastic contact FEM,a finite element mechanical model for interference fit between spindle and motor rotor at high rotating speed is established. The effects of the fit clearance and rotating speed (centrifugal force) on the stress,the displacement and the contact pressure on the interference-fitting surfaces are simulated.