FINITE ELEMENT ANALYSIS OF HIGH -SPEED MOTORIZED SPINDLE BASED ON ANSYS

EXECUTIVE SUMMARY

                          Finite Element Analysis is one of several numerical methods that can be used to solve complex problems and is the dominant method used today. Numerical solutions to even very complicated stress problems can now be obtained routinely using FEA. In practice, a finite element analysis usually consists of three principal steps, Preprocessing: Analysis, Post processing.

                                  

                               This paper presents a method to investigate the characteristics of a high-speed motorized spindle system. The geometric quality of high-precision parts is highly dependent on the dynamic performance of the entire machining system, which is determined by the interrelated dynamics of machine tool mechanical structure and cutting process. This Performance is of great importance in advanced, high-precision manufacturing processes. The state-of-the-art in machine tool main spindle units is focus on motorized spindle units for high-speed and high performance cutting.

                                 Different types of software are used for finite element analysis. Some of them are mentioned in this paper. As an example, taking the high-speed milling motorized spindle of CX8075 produced by Anyang Xinsheng Machine Tool Co. Ltd. The main specification of highly motorized spindle is discussed; Furthermore, the static analysis, modal analysis, harmonic response analysis and thermal analysis were done by means of ANSYS commercial software. The results show that the maximum rotating speed of the motorized spindle is far smaller than the natural resonance region speed, and the static stiffness of the spindle can meet the requirements of design. The results illustrate the rationality of the spindle structural design.

                  

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                             The results of static analysis show that the stiffness of spindle is 207.66N/μm, which is strong for a motorized spindle. The results of modal analysis show that the first-order natural frequency of the spindle is1054.6Hz, the first-order critical rotating speed is63,276rpm which is away from the maximum rotating speed of the motorized spindle, 12,000rpm. The results of thermal analysis show that the thermal deformation of spindle is 6.56μm, which is too small to affect the precision of the spindle.

                              The requirements of high-speed processing are meet by analyzing static and dynamic characteristics of the motorized spindle. The rationality of the spindle structural design is verified by FEM analysis. The result shows that the method to establish the finite element model of the bearing support by spring-damper element can be applied to the spindle component analysis and optimization. The FEA is an economical and easy process, so it has a bright future in our industries. But need of expert is necessary.