Analysis And Optimization Of The Bed Body Characteristics Of HT-4 Horizontal Machining Center

Manufacturing industry is the main body of the national economy,and it is the basis for establishing the country,the spirit of rejuvenating the country.In 2015,the State Council officially issued the “Made in China 2025”.China's manufacturing industry has entered a stage of vigorous development but it is also difficult to tackle.The machine tool is the foundation of the manufacturing industry and is called the "mechanical mother" in machinery.However,due to the late start of China's CNC machine tools,there is still a large gap between high-end CNC machine tools and Western manufacturing powerhouses.In response to these problems,China's machine tool design and manufacturing companies have introduced advanced design methods,developed innovative design concepts,and upgraded traditional manufacturing processes.This article takes the bed of HT-4 horizontal machining center of a machine tool factory in northwest China as the research object.On the basis of the completion of the three-dimensional model of the bed,firstly,a simulation model was established for three machining methods: machining center,milling,and drilling.The tool material and workpiece material were selected according to the actual working conditions.The simulation results were analyzed to determine the extreme value of the cutting force.Since the machine bed is in the basic position of the entire machining center component and is the only part of the machine tool system that is in contact with the outside world,the foot part connected to the bed and the ground is analyzed.Secondly,the knowledge of vibration theory is used to establish the mathematical model of the foot joint,and the damping in the model is transformed by proportional damping.Analyze the relationship between various factors of the foot and the performance of the bed,and the results obtained are important basis for the optimization of the bed structure behind.Next,the parameters of the stiffness of the joint between the bed and the ground are fixed.After the completion of the analysis of cutting forces and the analysis of the foot joints,the static and dynamic characteristics of the bed were analyzed using the finite element method.Based on the analysis results combined with the excellent performance of the honeycomb structure,multiple sets of bed structure improvement programs were proposed,and the basic dimensions of the honeycomb cells were determined through repeated optimization calculations.On this basis,multi-scheme optimization is performed,and the best scheme is finally selected using the grey correlation method.After the optimization,the first-order natural frequency of the bed is increased by about 22.2% from the original bed to about 301.5Hz from the original 246.67Hz;the static deformation and bed equivalent stress are reduced by more than 80%,and the bed is greatly optimized;The bed quality was reduced by approximately 7.21% while the performance was improved.