Analysis Of Hot Oil Carrying Characteristics About Hydrostatic Bearing Oil Film Of Heavy Vertical Lathe

As one of the most important parts of large-scale machine tool,hydrostatic bearing is widely used in heavy-duty CNC equipment,large wind power base,Metallurgical Industry,aerospace and other important fields.In recent years,foreign and domestic scholars have made lots of research on the oil film temperature of hydrostatic bearing.Usually,the research on oil film heating problem mainly focuses on two aspects of power loss,one is from the oil supply system,and the other is from the relative sliding of the supporting components.The part of heat affected by the hot oil carrying has been neglected.For this reason,this paper studies the temperature rise characteristic and the hot oil carrying laws of hydrostatic bearing oil film of heavy vertical lathe,taking the fluid mechanics,heat transfer,tribology and finite element analysis as the theoretical basis,and the simulation analysis is carried out by using the Fluent software.The main contents are as follows:Firstly,the flow equation of sector oil pad is deduced based on the parallel plate flow and annular gap flow mechanism.Then the temperature rise equation of oil film and the hot oil carrying factor are deduced according to tribology and heat transfer theory,and this paper established temperature-rise equation of hot oil carrying of hydrostatic bearing oil film.Secondly,according to the actual size of the oil pad,the geometrical model of the oil film is established.This paper divides the model by using the structured mesh.Then the hexahedral boundary layer is locally generated by the "O" mesh to improve the mesh quality.Through the simulation of the oil film flow field and temperature field under the condition of variable viscosity,this paper studies the hot oil carrying situation of oil film under the hydrostatic bearing running in different loads and rotating speeds,and reveals the occurrence law of hot oil carrying.These findings are important for increasing speed and enhancing carrying capacity of CNC machine tools.Finally,the hydrostatic bearing experiment is proposed to test the temperature characteristics of hot oil carrying of oil film,and the experiment process is recording the temperature of hot oil carrying under different rotating speeds and working loads.The theoretical results are compared with the experimental data to verify the correctness of simulation method,and the numerical simulation method is feasible for the research of the hot oil carrying of hydrostatic bearing.