< span style = "font size: 16px;" > in the machining process of modern high-speed and high-precision CNC lathe, the influence of thermal deformation on the machining accuracy of CNC lathe has been paid more and more attention. In order to realize rapid positioning, the worktable and tool holder need to move quickly on the guide rail surface. The friction between the worktable and the guide rail will produce a lot of friction heat, resulting in the thermal deformation of the guide rail. At present, researchers at home and abroad have carried out a lot of research work on the influence of thermal deformation of NC lathe guide rail on part machining accuracy and how to control and prevent thermal deformation. There are three main reasons for the thermal deformation of NC lathe guide rail: (1) Friction heat will be generated between the high-speed spindle and rolling bearing in the spindle box, resulting in thermal deformation of the spindle; (2) The friction heat between the ball screw and the nut causes the thermal deformation of the guide rail; (3) Friction heat is generated between the guide rail and the worktable, resulting in guide rail heat. When machining box parts on 6150 CNC lathe machining center, pay attention to: 1. When the 6150 CNC lathe has a face and a hole, the face shall be milled first and then the hole shall be machined; 2. Finish machining shall be carried out after rough machining of all hole systems by 6150 CNC lathe; 3. Generally, blank holes shall be prefabricated for holes with a diameter of no less than 30mm. Rough machining of the blank shall be completed on the ordinary 6150 CNC lathe with a reserved allowance of 4-6mm, and then semi finishing and finishing shall be carried out by the machining center. Holes with diameter less than 30mm can be directly completed by the machining center; 4.6150 in the process of NC lathe processing, large holes shall be processed first, and then small holes shall be processed.