3031 スクリュー圧縮機に使用するスパイラル溝スラスト軸受において潤滑油と冷媒との混合潤滑における摩擦測定 : ねじ圧縮機のすべり軸受(第14報)(S82-1 サステイナブル・トライボロジー(1),S82 サステイナブル・トライボロジー)

Abstract

The objective of this paper is to design development sliding plain bearings for hermetic screw compressors. The tests were carried out to obtain the data for bearing performance operating at an actual condition of refrigerant-blended lubricant. The thrust bearing used here is a groove type bearing with grooves on the runner and plane surface for the stationary side. The grooves are combination of spiral shape on outer side and radial shape on inner side in order to make reverse rotation possible. This configuration of the bearing is named 'The Ribbon Type Bearing' hereafter. At starting period, injection lubrication is applied to reduce friction torque. 'The Ribbon Type Bearing' is intended to achieve higher load capacity and lower bearing loss by the pumping effect and cooling effect of the both types of grooves in comparison with a conventional spiral groove bearings. The tests were carried out using pure lubricant and refrigerant blended lubricant containing refrigerant quantity of 6wt%, 10wt% and 44wt%. Bearing film thickness, bearing temperature, and friction torque were measured to evaluate bearing performance. The operating conditions were 2500rpm rotational speed and 370kgf bearing load. At that condition using 44wt% refrigerant blended lubricant, frictional torque was about 160kgf-cm. The potential of the ribbon type bearings were well demonstrated.