Analysis of Non-linear Machine Tool Dynamic Behavior

This paper presents a Finite Element Analysis (FEA) of a high speed spindle with variable bearing preload. ANSYS and SpindlePro were used to simulate the spindle model. The effect of preload on stiffness and frequency response function (FRF) was analyzed. A simplified model was simulated in SpindlePro to observe the thermal effects on back to back bearing configuration. It was found that gyroscopic moment is effective at lower damping ratios and stiffness. The bearing preload showed the greatest influence on the dynamic response. FRF was measured for different preload scenarios and stability lobes were calculated to analyze the preload effects.