Thermal Error Analysis And Experimental Study Of CNC Machine Tool Feeding System

With the development of manufacturing to high-speed and high-precision machining,the effect of thermal error on machining precision is becoming more and more serious.Therefore,reducing thermal error is an important way to improve the machining accuracy.As the slider and rail,bearing and lead screw and the friction between the screw and the screw will produce a lot of heat,so the feed system as the main CNC machine tool heat,temperature rise caused by the thermal error will reduce the machine feed movement of the accuracy.In this paper,the temperature field and thermal deformation of the rolling linear guide pair and the ball screw drive system are studied with the feed system of the experimental platform transformed from the VMC850 E vertical machining center produced by Shenyang Machine Tool Group.In order to reduce the thermal error of the feeding system Provide evidence.The main work of this paper is as follows:(1)In the aspect of theoretical research,through the research and analysis of basic theories and methods of heat transfer,such as basic mode and law of heat transfer,basic theory of temperature field and thermal deformation,and heat conduction differential equation,the rolling linear guide pair and ball screw drive system heat capacity and heat convection heat transfer coefficient of the calculation method and calculation process for the subsequent feed system temperature field and thermal deformation of the finite element simulation analysis provides the basis.(2)The finite element model of rolling linear guide pair and ball screw drive system was established.The thermal boundary conditions were loaded into the finite element model to analyze the steady state,transient temperature field and thermal-structure coupling respectively.The temperature field and thermal deformation of the ball screw drive system are analyzed by simulation analysis.The influence factors of the thermal error of the linear guide and the variation of the temperature field and the thermal deformation of the ball screw drive system at high feed rate speed are also studied.An effective method for thermal error of ball screw drive system.(3)According to the test objectives and performance requirements,design the overall structure of the test platform and test load loading mechanism,independent research and development of ball screw drive system thermal error test platform.(4)The experimental study on the temperature field and thermal deformation of the feed system on the test platform is carried out.The results of the experiment are compared with those of the thermal error simulation analysis,and the finite element analysis method is used to verify the temperature field of the ball screw drive system and thermal deformation results of the correctness.