Dynamic Characteristics of Hydrostatic Thrust Bearing With Tilting Oil Pad Under Eccentric Load

Abstract

During the processing of heavy machine tools, due to the effect of eccentric load, the oil film thickness changes, which directly affects the lubrication performance of the bearing. Therefore, this study takes the tiltable double rectangular oil pad hydrostatic thrust bearing as the research object and explores its dynamic characteristics. The study involves the analysis of oil film displacement response under eccentric loading conditions at different offset distances, loads, and sudden loads. Through analysis, the oil film damping coefficient and oil film dynamic stiffness of each oil cavity can be determined under different offset distances and loads. The research results show that the change in oil film thickness has a significant effect on the oil film stiffness. As the oil film thickness increases, the stiffness decreases, the ability to resist deformation becomes weaker, and the displacement response time becomes longer. Moreover, the dynamic stiffness is affected by the offset distance and the loading frequency. When the offset distance is 200 mm, the load is 24 tons, and the loading frequency is 50 rad/s, the oil film stiffness of the oil cavity 1 reaches 180 × 108 N/m. It is worth noting that the increase in dynamic stiffness of the sinking side is significantly greater than that of the floating side. Ultimately, this study provides a theoretical reference for evaluating the stability of hydrostatic thrust-bearing systems under eccentric loads.