Characteristic Analysis And Optimization Design Of VMC750 Vertical Machining Center Column

As the foundation of development of equipment manufacturing industry,machine tools have been widely applied in the manufacturing and processing center because of its high efficiency.The column is the key part of the machining center.The accuracy and quality of the parts processed by the machine tool will be affected by its working performance.Therefore,the column structure static and dynamic performance analysis becomes one of the topics of great practical significance in the field of machine tool manufacturing to use the optimization design theory to reduce the weight of the machine tool under the premise of ensuring the machining accuracy and stiffness.In this paper,the static and dynamic characteristics of VMC750 vertical machining center column are obtained by finite element analysis.Through analysis,the weak links of the structure are found,and then the lightweight design is carried out.This paper mainly includes:(1)The solid model of the column was established,and the simplification of the model and the calculation of the cutting force under the extreme working condition were completed on the Design Modeler platform of Workbench software.Through static analysis and modal analysis,the optimized part of the column structure of VMC750 vertical machining center was found.It provides the performance index for the subsequent topology optimization with the combined strain energy index as the design objective.(2)The unit density is taken as the design variable,and the combined strain energy index is taken as the design objective.Under the constraint of volume ratio before and after optimization,the topological optimization of the column structure of VMC750 vertical machining center is carried out based on the theory of variable density method.According to the material removal and retention distribution of the column after topology optimization,the column structure was redesigned to analyze the deformation and various modes.Compared with before topology optimization,the static performance is basically unchanged,the first-order natural frequency is increased from82.549 Hz to 99.979 Hz,and the weight loss is 9.7 %.(3)Based on the sensitivity analysis,the size optimization design of the original structure of the column and the structure after topology optimization of the column is carried out.The former takes the thickness of the outer wall of the column,the thickness of the Internal longitudinal reinforcement plate,the transverse reinforcement plate and the diameter of the side wall hole as the optimization elements,and the latter increases the two Χ-shaped structures formed after the topology optimization of the column structure.After completing the parametric setting in Solid Works,the screening method was used in ANSYS Workbench to obtain the best optimization scheme,and then the re-modeling was carried out to analyze again.Finally,the performance of the columns after two sizes optimization was compared.In the case of basically the same deformation,after the topology optimization of column structure,the size optimization again reduces the weight by 2.8 % compared with the size optimization of the original structure directly,and reduces the weight by 11.6 % compared with the original structure,achieving the purpose of optimization performance.The research results show that the two structural optimization design methods can reduce the weight of the machining center,especially the size optimization effect after topology optimization is better.The above analysis can also provide reference for the optimization design of other parts.