DETECTING METHOD OF DAMAGE OF ROLL

摘要

PURPOSE:To accurately and easily detect the damage of a roll and prevent an accident, by discriminating a prescribed frequency component from an acoustic emission signal which is generated from the roll and by comparing the output increase ratio of the frequency component with a reference value. CONSTITUTION:The frequency component of 50-500kHz of an acoustic emission signal, which is generated from a roll at rolling work, shows a high output increase ratio when the roll is damaged. A detector 3 is mounted near the super hard alloy member 2 of the roll 1 to detect the acoustic emission signal. The detected signal is transmitted by a radio transmitter 4 and received by a receiver 5. The received signal is supplied to a frequency discriminator 7 through an amplifier 6. The frequency discriminator 7 detects the frequency component of 50-500kHz and applies it to a comparator 8. When the increase ratio P exceeds a reference value P1 in the comparator, an alarm 9 is operated. The damage of the roll is thus accurately and easily detected.