Some key pre-processing technologies in rolling mill vibration monitoring

In working environment of rolling mill, speed of rolling mill was changing and rolling mill had impact. Changing speed brought out problems of distorted time-frequency feature of vibration signal. To solve these problems, the paper proposed a software interpolation and re-sampling method for the rotational speed changing. Since impact signal had the frequency information over the whole frequency domains, and mixed with noise signal, a feature extraction method based on zero lag high order Cumulants and the wavelet analysis for impact signal was proposed, which suppressed not only white noise but also colored noise. Both of the pre-processing methods were effective for engineering application.