Observation of oil film of floating bush bearing using X-ray CT and examination of effect of oil film region on friction loss

Abstract

The floating bush bearing has a floating bush inserted between the bearing and the rotating shaft. Because of this，this bearing during bush rotation is one of the greatest concerns. In this study, the oil film was observed in a region where the shaft rotation speed was relatively low and the bush rotation speed tended to increase using X-ray computed tomography. This visualization method has the advantage that the oil film can be observed regardless of the bearing structure by CT images. From the acquired CT images, it was revealed that the oil film area in the inner clearance shrinks in the circumferential direction as the rotation speed increases. This phenomenon was caused by the fact that the lubricating oil in the outer clearance is supplied to the inner clearance by the oil film pressure due to the wedge action.