The Study On Dynamic Characteristics And Optimum Design Of Four High Rolling Mill

Four high rolling mill,the most basic equipment for rolling,plays an important role in the production of plate and strip.Our country's four high rolling mill mainly relies on the traditional static design method for production and manufacturing,based on the existing equipment transformation to improve the dynamic performance of the rolling mill.Compared with the static design method,mechanical products manufactured by dynamic design method have the advantages of high precision,good vibration resistance,low cost and long service life.In this paper,the dynamic characteristic calculation and the response calculation under static and multi frequency excitation load of rolling mill parts are carried out by using the method of connecting multi-component with contact surface.In the structural design of the target dynamic characteristic parameters of complex structure,the structural parameters with the target natural frequency are obtained.In the structural design of complex structures aiming at reducing the dynamic response,the structural parameters with relatively low dynamic response are obtained.The main research contents of the thesis are as follows:(1)In Solidworks,the three-dimensional model of rolling mill parts is established,which is imported into ANSYS Workbench,and the finite element model of rolling mill parts is established.(2)Through the modal analysis of the rolling mill components,the first 10 natural frequencies and modes with and without damping are obtained,and the influence of the roll gap on the natural frequency of the stand is explored.The static response and multi frequency excitation dynamic response of rolling mill components are calculated,and the stress and deformation of rolling mill components are obtained.(3)Combined with experimental design,response surface method,genetic algorithm and sensitivity analysis method,taking the quality and low-order natural frequency of rolling mill components as the goal,taking its size as the design variable,the design model is established,the structural parameters of rolling mill componentswith the target natural frequency are determined,and the frequency change design of complex structure is realized.(4)Combined with the test design,response surface method,genetic algorithm and sensitivity analysis method,the design model is established with the quality,maximum deformation and maximum stress of rolling mill parts as the goal,and its size as the design variable.The structural parameters with relatively low dynamic response of rolling mill are determined,and the dynamic response design of complex structure is realized.In this paper,according to the theory of structural dynamic design,the target dynamic characteristic parameters of complex structure and the structural design aiming at reducing the dynamic response are carried out.The structural parameters of rolling mill structure with target natural frequency and relatively low dynamic response are determined.The good dynamic characteristic and response of structure are established in the design stage of structural natural frequency and dynamic response.The research results obtained in this paper can provide some reference and guidance for the dynamic design and transformation of other equipment.