VIBRATION SIGNAL EMISSION FROM MONO-SIZE PARTICLE BREAKAGE

A technique based on vibration measurement and analysis was used to st udy the breakage of mono-size dolomite on a hydraulic press. Up to a m aximal pressure of 4 MPa, vibration signals during pressing and breaka ge of dolomite were picked up with two piezo-electric type acceleromet ers, which were screwed on to the breakage chamber and oriented in per pendicular directions. The source vibration signals were amplified and stored on a DAT recorder. A ''stereo'' picture was built-up for descr ibing the breakage events based on two-channel vibration signals. The saved time-domain waveforms were converted into digital format for the personal computer; thus, the breaking history may be replayed by plot ting and zooming the waveforms, from which the frequency-domain power spectra were transformed, Primary studies showed that the most signifi cant changes on the power spectra were on the frequency range of 500 t o 2500 Hz, and were caused mainly by changes in the feed sizes to the crushing chamber, Relations between the vibration signal characteristi cs and the parameters in mono-size breakage events were derived by mul tiple regression based on principal component scores. It is shown that vibration signal measurement may provide additional information for s tudying single particle breakage events. Two examples are used to demo nstrate the application of principal component analysis.