The FEA And Optimization Of Special Milling Key Components For Large Cylindrical Inner Circle Parts

Large cylindrical parts inner circle special milling machine is the product of JiangsuHigh Precision Mechanical and Electrical Equipment Co., Ltd. which is designed for largecylindrical parts processing and repair. As the structural is designed based on the experienceof designers, structural design is not reasonable, the accuracy is much lower than the sametype of machines abroad. The paper offers a good reference in structure design andoptimization for large machine tools.The research object of the paper is the large cylindrical parts inner circle special millingmachine. First, calculate the possible maximum loads of key supporting parts in normalworking conditions, then, simplify solid components and establish3D model in Pro/E, getthe maximum deformation by FEA, and find out the weak points of supporting parts.Identify the connection relationship of the shaft and bearing, FEA model of spindle isestablished with the spring damping unit instead of bearing structure, obtain the vibrationcharacteristics through modal and harmonic response analysis. The relationship of spindlebearings distance, bearing arrangement and dynamic characteristics of spindle system isanalyzed. Through optimization, the first3natural frequencies of spindle is increased by19%. as the column and slipway consist of multiple repeated cell body structure, throughmulti-objective cell body optimization, weight of the column is decreased by6.4%, the1ST,3RDand5THnatural frequencies increased by8.2%,12.6%,7.6%. Weight of the servo isdecreased4.3%, first three natural frequencies increased by5.5%,4.1%,6.5%.As the company’s machine tool were not designed through FEA. This project provideshelps in machine optimization. The optimization method based on cell body simplifies thecomplicated structure modeling process, improves the efficiency of optimal design, it can beapplied to other structures with repeated structures in mechanical product design.