Study On Thermal Performance Of Conical Hydrostatic Bearings

Conical hydrostatic bearing is a special form of hydrostatic bearing, which has the advantage of high accuracy, high stiffness, and high stability. Therefore it has a good application prospect in the field of precision ultra-precision processing. However, the temperature rises up due to the viscous dissipation of lubricating oil when the bearing is working. This will not only change the viscosity of the oil, but also cause obvious thermal deformation of the bearing parts. So the study of conical hydrostatic bearing thermal state performance has great significance to improve the performance and precision of this kind of bearings. Therefore, a research is developing to explore the thermal state performance and the changing law of conical hydrostatic bearing, which is based on theoretical analysis, numerical simulation and experimental research.The thermal state performance of the conical hydrostatic bearing is analyzed in theory. The mechanism of heating and heat transfer is assumed. Based on the assumption of adiabatic and constant viscosity, the calculation formula of temperature rising is derived. The mathematical model of thermal state of conical hydrostatic bearing is built, which provides a theoretical basis for numerical simulation.On the basis of theoretical analysis, the conical hydrostatic bearing thermal analysis numerical simulation model is built. The temperature field distribution and the changing law of the conical hydrostatic bearing is obtained by the simulation. The viscosity change and thermal deformation after temperature rising is calculated. Then the influence of temperature rising on static performance and working precision of the bearing is analyzed. The results show that the parameters such as speed, oil pressure, oil film clearance of conical hydrostatic bearing have a great influence on the thermal state performance.An experiment is carried out to verify the above rules on the self-built thermal state performance experimental platform. The temperature rising and thermal deformation under different speed, oil pressure and oil film clearance is measured, and compared with simulation results. The data matches well, which prove the rationality of the model and the reliability of the simulation results.A series of measures to improve conical hydrostatic bearing’s thermal state performance is summarized systematically. The thermal state performance is improved by some measures.Through the above research, a relatively perfect conical hydrostatic bearing thermal analysis method is established. The thermal state performance of the bearing and its change law is basically grasped. The results of the study have certain guiding significance of designing the conical hydrostatic bearing and optimizing its thermal state performance.