Study On Thermal Characteristics Of Ball Screw System Of High Speed CNC Machine Tool

With the development of aerospace and shipbuilding industry,the requirements of all kinds of industrial products for machine tools are becoming higher and higher.Because of the characteristics of high precision,high efficiency and high rigidity,ball screw pair is usually the main executive part of the feed drive system of high-speed CNC machine tools,and its performance directly affects the running state and machining accuracy of machine tools.In the process of machine tool running,a lot of heat will be produced in the contact area of ball screw feed system,if the heat can not be dissipated in time,it will lead to the rise of temperature of mechanical parts in the feed system,thus causing thermal deformation,which is the main factor affecting the accuracy of the lead screw,therefore,the research on the thermal characteristics of ball screw is beneficial to improve the machining accuracy of the machine tool,and is of great significance to reduce the machining error of the machine tool.The main research contents of this paper are as follows:First of all,through consulting the domestic and foreign literature and research practice,to understand the different ball screw system,understand its working principle and composition,and analyze the factors that cause the temperature change of the lead screw,based on the thermodynamics theory,carry out theoretical modeling.Secondly,the three-dimensional model of hollow ball screw system is established and simplified in Pro/E software,and then it is imported into ANSYS for simulation analysis,the temperature field of hollow lead screw and the temperature change of hollow lead screw and nut with time are obtained.By analyzing the temperature and deformation of hollow lead screw,the influence of different working conditions and different cooling strategies on the accuracy of hollow ball screw system is discussed,it provides theoretical basis for cooling strategy and working condition selection of hollow lead screw.Finally,taking the ball screw pair provided by HANJIANG Machine Tool Factory as the experimental object,the thermal characteristic experiment is carried out on the HIS64 lead screw forced cooling test-bed,and the measured data is shown in the form of line chart,and compared with the results of the previous simulation,the relative error between the two is calculated to verify the correctness of the simulation results.In this paper,the temperature changes of hollow ball screw under different working conditions and different cooling strategies are discussed,and their effects on the deformation of the screw are analyzed,which provides a theoretical reference for the analysis and further study of the thermal characteristics of hollow ball screw.