Dynamic Finite Element Analysis of Ultra-high Speed Grinding Spindle System

The 3D finite element model of spindle system on ultra-high speed grinder was built up by use of finite element analysis software ANSYS,and each order natural frequency and mode shape were obtained through modal analysis. The influence of the centrifugal force produced by high speed in ultra high speed grinding process should not be neglected,and each order natural frequency and vibration model were obtained by static analysis of spindle system first and modal analysis second. By comparison,the natural frequency of spindle system was increased after considering the pre-tightening force. The critical speed of each order natural frequency was calculated by the formula,and it provided theoretical guidance to avoid the resonance frequency of grinding. The harmonic response analysis of the spindle system was applied by using modal superposition method to consider the influence of vibration force,and the amplitude frequency response curve of spindle mid span with the change of excitation frequency was gotten and the excitation frequency which would lead to resonate was identified. The technology measure enhancing dynamic characteristics of spindle was put forward.