热连轧机工作辊水平-垂直非线性振动特性及抑制

摘要

Work roll vertical-horizontal system's nonlinear vibration model of a hot strip tandem mill was established based on the rolling interface horizontal-vertical direction friction mechanics mod-el and the dynamic rolling force model,with the influences of mill structures and the frictions between work roll bearing seats and memorial arch pillars considered.The amplitude-frequency characteristics equation of the system was obtained by using average method,and the characteristics of amplitude-frequency were analyzed under the effects of the factors such as the extraneous forces and nonlinear parameters,which provided theoretical guidance for the suppression of work roll system vertical-hori-zontal vibrations.Different vibration states such as periods,doubling periods,chaos were exhibited a-long with the extraneous force amplitude changes when analyzing the system Lyapunov index and dis-placement bifurcation diagram.Finally,a method of inhibition of horizontal vibrations and vertical vi-brations was presented based on the influences of scaleboard gaps on system vibrations and the analy-ses of amplitude-frequency characteristics under circumstances whether there were scaleboard gap or not between work roll bearing block and arch column.The results of simulation and practice show the effectiveness of the method.%基于振动情况下轧制界面水平-垂直方向摩擦力模型和动态轧制力模型,考虑轧机的结构和工作辊轴承座与牌坊立柱间的摩擦力等因素的影响,建立了热连轧机工作辊水平-垂直系统的非线性振动模型.运用平均法求解得到幅频特性方程,分析外扰力和非线性参数等因素对系统幅频特性的影响,为抑制轧机工作辊水平-垂直振动提供理论指导.通过分析李雅普诺夫指数和位移分岔图,发现系统随外扰力幅值变化表现出周期、倍周期和混沌等不同运动状态.最后,通过分析工作辊轴承座与牌坊立柱间有无衬板间隙这两种情况下的幅频特性及衬板间隙对系统振动的影响规律,提出一种抑制工作辊水平振动和垂直振动的方法,仿真和实验结果均表明该方法有效.