Optimization Research On Lubrication Performance Of The Hydrostatic Thrust Bearing With Double Rectangular Cavity

Hydrostatic thrust bearing is the core component of heavy-duty machinery because its high running accuracy,good stability,low power consumption,vibration absorbing and long working life.With the development of modern industry,the demand for rotation speed and carrying capacity of-numerical control equipment becomes higher and higher.Under the extreme condition of overloading,micro gap and high velocity,shear heat rises,lube viscosity decreases,oil film thickness becomes thin and unequally distributed,local boundary lubrication and dry friction appear,which further causes the tribological failure and severe static pressure loss.Therefore.the structure parameters of static pressure thrust bearing pad are optimized to achieve high carrying ability and low temperature rise of oil cushion and to solve the above problems.In this paper,oil pad with double rectangular cavities as the research object,the lubrication performance of oil film is studied under the condition of high-speed and heavy-duty.With the three-dimensional software UG,the oil film model of oil pad with double rectangular cavities is defined;mesh is divided and oil film boundary conditions are set respectively in the ANSYS ICEM CFD and ANSYS CFX;under the same speed and load condition,the pressure field,temperature field and velocity field of the oil film with different oil cavity depth and different cavity area are simulated,the influence of cavity parameters on lubrication performance is concluded,oil cavity depth and cavity area are obtained by analyzing data;when the oil temperature is certain,high bearing capacity as the objective function,optimal cavity area is solved by MATLAB;under the same operating condition,the pressure field,temperature field and velocity field of oil film with different oil hole position and hole diameter are simulated to confirm the position and diameter of oil hole.In order to verify the correctness of the theoretical calculation and simulation analysis,the experimental study is conducted on the five meters vertical CNC lathe in the Qiqihar heavy CNC equipment co.,LTD.The same position of oil pad before and after the optimization is measured to get the oil film temperature,oil film pressure and oil film thickness,the relationship between lubrication performance and speed and load of workbench is analyzed,the correctness of theoretical analysis and simulation results is verified.