Investigation of Bush Rotation Speed of Floating Bush Bearings by Oil Film Observation Using X-ray CT

Abstract

A floating bush bearing has a double oil film, which is difficult to observe using traditional methods. In this study, the oil film of a floating bush bearing is observed using X-ray computer tomography. By appropriately processing the acquired CT images, double oil films can be observed efficiently. The CT images show that the oil film area decreases in the inner clearance and does not change in the outer clearance when the increase of the bush rotation speed is suppressed despite the increase in the shaft rotation speed. This phenomenon can be explained by the oil film area of the inner clearance decreasing under the influence of the centrifugal force acting on the oil film. When there is enough oil in the inner clearance, it is observed that the bush rotation speed increases linearly. These results indicate that the bush rotation speed is closely related to the oil film area of the inner clearance.