AXIAL LOAD-CAPACITY OF WATER-LUBRICATED HYDROSTATIC CONICAL BEARINGS WITH SPIRAL GROOVES FOR HIGH-SPEED SPINDLES

In this paper, two types of water-lubricated hydrostatic conical beari ngs with spiral grooves for high-speed spindles are investigated. One has a rigid bearing surface and the other has a compliant one. In thes e bearings, pressurized water is first fed to the inside of the rotati ng shaft and then introduced into spiral grooves through feeding holes . Therefore, water pressure is increased due to the effect of the cent rifugal force at the outlets of the feeding holes by shaft rotation an d, furthermore, water pressure is also increased by the viscous pump e ffect of spiral grooves. The static characteristics of these bearings are theoretically predicted and calculated results are compared with e xperimental results. It was found that the compliant surface bearing h ad a larger load capacity in a relatively large bearing clearance than the rigid surface bearing, and lower bearing power consumption in a s mall bearing clearance although the load capacity is reduced. (C) 1998 Elsevier Science Ltd. All rights reserved.