Coupled Dynamic Model Building and Simulation of Vertical Vibration of 4-high Rolling Mill

Considering the dynamic characteristic of the flow of metal in the rolling process, the dynamic second flux of metal theory is put forward. Based on this theory, the dynamic model of the deformed metal is established; the dynamic model of rolls for four high mill is established according to the symmetry of rolling mill. Coupled the dynamic models of the deformed metal and the rolling mill, the coupled dynamic vertical vibration of the rolling mill is established. Based on Matlab/Simulink platform, the influences of the technological parameters on the vertical vibration of mill were analyzed. Simulation results show that, the welded seam and the incoming strip have strong influence on the roll gap and draught pressure, in the step responses, the overshoot is big and the adjusting time is long. This influence can be controlled by decreasing the rolling speed and increasing the damping coefficients. It is no use to adjusting the forward tension and backward tension for controlling the vibration.