Tilt Angle of Hydrostatic Spindle Influenced by Microscale Effects

Abstract

Machining error in machining processes arises due to several factors. The tilt angle of the spindle of the machine tool is one of the important factors that directly affect the shape error, surface quality, and roughness of the machined part. In order to better analyze the effect of microscale effects on the tilt angle of a hydrostatic spindle, a fluid control model at the microscale is introduced into the traditional Reynolds equation. The static performance characteristics of hydrostatic bearings with four and eight pads under the influence of velocity slip are obtained. The results show that the existence of velocity slip improves the stiffness of the bearing. However, the influence of velocity slip on the tilt angle is obvious, and the tilt angle decreases as the increase of velocity slip. The experimental results verify the existence of velocity slip at the microscale indirectly and provide a theoretical basis for the study of the performance of liquid hydrostatic bearings at the microscale.