Work rolls vibration characteristic under multi-source excitation in hot strip tandem mill

Abstract

The severe vibration of hot strip tandem mill is general problems, when it rolls high strength and thin strip. For the study of this problem, the online monitoring system is used to obtain the vibration signal. The motor output torque, the hydraulic cylinder oil pressure and the work roll acceleration have similar frequencies by Fourier transform. This problem motivates analysing and predicting the mill dynamics by using a finite element models. The simulation models developed in the ANSYS environment is used to calculate the natural frequencies and mode shapes, and distinguish the effects of motor torque excitation, hydraulic excitation, and combined-excitations. Both the vertical vibration and horizontal vibration were investigated. The maximum displacement and amplitude of chatter frequency were larger in the horizontal than in the vertical. To reduce chatter vibration, a method of inhibition of horizontal vibration and vertical vibration has been presented. The simulation results and experiment both show that the method is effective.