轧机扭转自激振动分析

研究轧辊黏滑运动引起轧辊扭转自激振动和自激振动对带材表面质量影响 .在分析轧辊工作界面的黏滑运动基础上 ,建立轧辊转动动力学方程 .根据轧辊与带材之间黏着和滑动特点 ,对滑动非线性摩擦力进行线性化处理和求解动力学方程 ,分析扭转振动特性得出 :随着黏着时间的减少 ,扭转振动的波形逐渐由锯齿形变为正弦形 ,摩擦自激振动可以表现出低于自由振动频率的所有频率分量 ;黏着时间与扭矩增量成正比 ,与转动轴刚度和传动轴转动速度成反比 ,滑动时间基本稳定 ,黏着时间越长 ,系统吸收的能量和释放的能量越多 ,由于滑动时间一定 ,容易引起带材表面剪切冲击和表面条纹 .工业现场测试表明轧机存在工作辊扭转自激振动 .图 7,表 3,参 8.

Analysis of torsion self-excited vibration in rolling mill

This paper investigated torsion self-excited vibration of roller which accused by stick-sliding movement and torsion self-excited vibration of roller which influence on strip's surface quantity. Dynamics equations of running roller were derived based on analyzing sticking-sliding movement of working interface. Non-line sliding friction force was lineated and the solution of dynamics equations were founded based on characteristic of stick and sliding movement. It educed that hackle wave of torsion vibration turns into sine wave along with sticking time reducing. The frequency of friction self-excited vibration is approximately equal to frequency that of natural vibration. Sticking time is direct ratio with tweak increment and inverse ratio with torsion stiffness and speed of axis of rotation, the sliding time is stabilization, the sticking time is longer, the system absorbs and stores more energy, because sliding time is short ,it is easily causing cutting impact on strip surface. Industry scene measure indicates that there are torsion self-excited vibration of rolling mill.7figs.,3tabs.,8refs.