The Structural Optimization And The Casting Process Design Of The Key Parts Of Vertical Machine Center

Machine tools are the base equipment of modern manufacturing industry, which arewidely and deeply applied in many kinds of industries. For a long time, the design worksof machine tools are still in the stage of experience analogies and static design withexcessive margins and stagnant design level. Meanwhile, the manufacturers do not payattention to the improvements and innovations of producing process. It leads to highenergy consumption sand produces various detrimental emissions. And the quality ofmachine tools castings cannot be improved. According to the situation, the collaborativedesign and optimizations of machine tools structures and casting process base on CAEmethod are quite necessary due to the effectiveness and convenience of virtualexperiments. Furthermore, the research and development of green manufacturing processwith high efficiency and low cost are especially urgent and significant.A vertical machining center was studied in this paper. The key parts were analyzed withstatic and dynamic parameters based on FEM software (ANSYS Workbench), includingthe strains and stresses distributions, the natural frequencies and the vibration modes. Itwas found that the deformations of these parts within the limits of the geometry accuracychecking standards for vertical machining centers, the structures stiffness meet therequirements. But both the low orders of natural frequencies of the base are low, whichpossibly lead to resonance. On that basis, the parametric models of the column andmachine base were set up by making use of UG Modeling functions. The bidirectionaldata connectivity between UG and ANSYS Workbench was founded. Then a multiobjective optimization of the structures was completed with Central Composite Designexperiments. Response Surface Method was applied to set up the optimization models.Combining the dimensions sensitivities and the casting process constraints, optimaldimensions and modified structures were proposed. The conclusions are as follows: themass of standing column was reduced by92.69kg while the natural frequencies (1stand2nd) were raised up by4%-5%;the natural frequencies of the machine base was seriouslyaffected by the chip groove, therefore a better reinforcing plate structure and modified suggestions were presented. It shows that the1stof order of the base was raised above to200Hz, avoided the resonance interval.Finally, the column was typically discussed for the collaborative design andoptimizations of the structures and the casting process. The dry sand casting process andthe gating system were designed for the column. After co-simulation for the castingprocess, improved process and casting structures were proposed.