An Analysis On Strip Vibration Coupled With Vibration Of Main Mill Drive System Of Rolling Mill

For many years,many scholars at home and abroad have been devoted to the vibration research of rolling mill which has been the key problem that affects the quality of strip steel.The key to the study of strip vibration is the treatment of boundary conditions.In the previous studies,most of the steel strip models are simplified as axially moving strings and beams.When the boundary conditions are simply supported,hinged,fixed,inertia and so on,the effects of the main drive system are seldom considered.Therefore,it is necessary to consider the influence of the main drive system of the rolling mill on the vibration characteristics of the strip.Based on the study of the mechanism of strip and roll in rolling process,the nonlinear vibration of strip is considered in this article.Based on the nonlinear theory and the energy method,the strip is simplified as an axially moving Euler beam.The main transmission system is connected with the steel strip through the roller.By using the lumped mass method,the main drive system is simplified into a single degree of freedom system and a multi degree of freedom system.And the continuous discrete coupled vibration model is established for the torsional vibration of the main drive system and strip transverse longitudinal vibration.The nonlinear vibration differential equation of the model is established according to the Hamilton principle.In the process of solving,the Kantorovich time average method is used to simplify the equation,and then the first order and two order iterative solutions of the coupled differential equations are solved by using the modified iteration method respectively.The amplitude frequency response curves of the coupling system are carried out by simulation software,and then the effects of strip strip tension,axial velocity,roll moment of inertia and torsional stiffness on the vibration characteristics of the strip are discussed.Finally,a comparison between the single degree of freedom rolling mill main drive system of rolling mill and two degrees of freedom of the main drive system is given.Through the comparative analysis,the impact of the main drive system of structure parameters on the vibration of the strip can be further understood.And the research results can provide a theoretical reference for the analysis and control of rolling mill vibration in engineering practice.