Study On Vertical Vibration Characteristics Of Rolling Mill Based On Lubrication And Friction Effect Of Rolling Interface

Metal strip is used extensively in the military,construction,automobile,and other industries due to the rapid development of the industrial;however,vertical vibration of rolling mill will destroy the stability of rolling production and have an impact on the effectiveness and quality of strip production.Based on the theory of mechanical vibration,a dynamic rolling force model based on the lubrication and friction effect of rolling interface is established in this paper,and the vibration characteristics of the four-DOF rolling mill system are analyzed.The main contents are as follows:(1)The influence of the parameters such as tension fluctuation,rolling speed and reduction rate on the vertical vibration is analyzed theoretically.It is proposed that changing the lubrication friction state of the rolling interface can effectively avoid the occurrence of vertical vibration.Combined with the actual production data,the characteristics of the lubrication fluid and the influence of rolling parameters on the friction coefficient of the rolling interface are analyzed.Finally,the research method of vertical vibration is given.(2)Considering the effect of vertical vibration velocity,the Karman differential equation was optimized and linearized,solving the unknowns in the differential equation,such as the total friction stress and deformation resistance,and the dynamic rolling force model was obtained by integral method.The model was verified and analyzed by combining with the actual production data.(3)According to the mechanical structure of the four-high rolling mill,a four-degree-of-freedom vertical vibration model was established,the corresponding dynamic equation was given,the inherent characteristics of the rolling mill system were analyzed,and the response equation of the system was solved by multi-scale method,and the effects of different nonlinear parameters on the vibration characteristics were analyzed.(4)Taking 1780 rolling mill as the test object,the experimental research was carried out,and the work roll bearing seat,supporting roll bearing seat and frame were set as the measuring points.The dynamic signal acquisition instrument was used to collect and analyze the vibration signals,and the correctness of the simulation results was verified.