RESEARCH ON THE VIBRATION OF COLD ROLLING MILL F5 UNDER MULTI-SOURCE EXCITATION

Serious vibration occurred on the F5 stand when producing thin strips on a 1550 cold tandem mill. The field test showed that the dominant frequency of the vibration is 144 Hz, which was close to the natural frequency of the F5 stand. Moreover, there were many excitation frequencies in the strip excitation spectrum and the servovalve pressure spectrum of the screwdown system. To explore the vibration source and suppress the vibration, the industrial field experiment was conducted to concluded that the vibration was affected by the joint excitation of strip steel and the hydraulic screwdown system. The characteristics of different frequency combination acting on the mill were obtained by solving the model of the strip-screwdown excitation. A method was proposed to suppress the vibration. It used the desired excitation combination by adding the vibration suppressor in the control system to eliminate a specific frequency. The satisfactory suppression effect was obtained after the implementation. The research provides a reference for analyzing vibration mechanism of cold tandem mill and expands the method of vibration suppression.