Application of vibration signal measurement for monitoring grinding parameters

Abstract

Vibration signal measurements are discussed for monitoring operating parameters in a laboratory-scale ball mill. The vibration signal was first picked up with an accelerometer, amplified by a vibrometer and then transmitted to a DAT recorder during the entire testing period. The signal on the DAT recorder was resampled and converted into IBM compatible personal computer readable data format using a digital oscilloscope. The vibration signal analyses included rms estimation, power spectral estimation, waterfall plot, principal component analysis and stepwise multiple regression analysis. Clear differences in the rms and the spectra are found for different grinding conditions. Three principal components described about 95% of the total variation in the spectra. Each principal component was related mainly to one to three major frequency bands. Close correlation was found between the vibration signal and grinding parameters. Therefore, an alternative method can be developed for monitoring the operating parameters in a ball mill.