Finite Element Analysis And Optimization Of Working Table Components Of The Vertical Machining Center Based On ANSYS

The machining accuracy of CNC machine tools is subject to many factors,static and dynamic characteristics of CNC machine tools are two of the importantfactors. The information gained in finite element analysis of the assembly as awhole is usually hard to gain from the analysis of single component. In this paper,the assembly, which is composed of base, saddle and working table of the FM6324Vertical Machining Center, is used as the object of study, and ANSYS is used as theanalysis tools. Static analysis and modal analysis of the assembly are accomplished.Static characteristics and dynamic characteristics are gained, and size optimizationis completed at last.In this paper, the theoretical knowledge of the machine is introduced at first.Then finite element analysis methods and theories of contact relationship ofassembly are discussed. After that, the object of study, FM6324Vertical MachiningCenter, is presented.During the static analyzing, contact analysis is completed using ANSYS tohandle assembly relationship,4working conditions are considered and analyzed.Strain diagrams and the stress diagrams of these working conditions are obtained,and the strain and stress situation is grasped. Then, one of the working conditions isselected for modal analysis and optimization.During the modal analyzing, the junction theory is considered. Thecombination element is used to simulate dynamic characteristics of combinedinterfaces. Then dynamic characteristic parameters of the combined interfaces aregained based on Masataka Yoshimura method. Then, the top5order modalfrequencies and mode shapes are obtained.In the optimal design, GUI operation during the ANSYS analysis is convertedinto the APDL commands at first. These APDL commands are modified to analyzeassemblies with slightly different sizes automatically and rapidly. Then4sizes ofthe ribs and2junction area are selected as optimization variables, and5size levelsare designed for each variable,25size combinations are made up based on theorthogonal experimental table. The body weight, deformation and frequencies inthe results are selected as the optimization targets. Analysis is repeated using the APDL command. Finally, these analysis results are processed and a better result isobtained.