The Effect of Lubricant Viscosity Change on the Performance of Hydrostatic Thrust Bearings

The lubricant temperature rise in hydrostatic bearings becomes large under the condition of high load and high speed operation. Therefore the effects of lubricant viscosity change on bearing performance are not negligible. In this study, the performance characteristics of capillary compensated multi recess hydrostatic thrust bearings are analysed theoretically and experimentally considering the lubricant viscosity change. The relations between the lubricant viscosity change and the load carrying capacity or the bearing clearance variation are shown quantitatively. The close agreement was obtained between theoretical results and experimental ones. Consequently, it was pointed out that the hydrostatic bearings should be analysed considering the lubricant viscosity change.