热连轧机自激振动诊断与振动机理分析

Analysis and Diagnosis of Self-Excitation-Vibration of Hot Rolling Mill

描述了热连轧机的现场多点振动测试方法,利用振动信号的功率谱分析和小波包分析等现代信号分析技术,深入研究了轧机自激振动机理并诊断了振源位置。分析结果表明,研究对象的轧机压下系统位移传感器定尺支座结构是引起系统不稳定的敏感部位。该结构参数不合理,是导致压下系统反馈信号严重失真,诱发轧机工作机座自激振动的根源。分析结果和诊断结论对于制定合理的结构动力学修改策略,消除轧机自激振动具有重要的意义。

An approach of field multi-point vibration test for hot rolling mill housing is presented. The self-excitation-vibration mechanism is studied and the vibration source is detected, both using the techno logy of power spectrum analysis and wavelet package analysis of vibration signal. The analysis showes that the structure of feedback path displacement sensor is the sensitive factor leading to the AGC system unstable. Unreasonable structural parameters of the displacement sensor result in serious distortion of the displacement feedback signal, and induce the self-excitation vibration of the mill housing. Results of the ana- lysis and the diagnosis are helpful for establishing the strategy of structural dynamics modification and vibration restraining of hot rolling mill.