METHOD OF DIAGNOSING TIMING FOR REPLACING WORK ROLL OF TENSION LEVELER

PURPOSE:To prevent the failure and jump out of the work rolls of the tension leveler by deciding the point of the time when the bending of the work rolls or the difference between the circumferential speed of the work rolls and the traveling speed of a strip exceeds a prescribed value as the timing for replacing the work rolls. CONSTITUTION:The work rolls 42 disposed to work roll units 5, 8, 9 are pressed onto the traveling strip 3 from above and below to correct the shape of the strip 3 in the traveling state. The bending of the work rolls 42 is measured by bend measuring sensors and the circumferential speed of the work rolls 42 is obtd. from rotating speed sensors. The traveling speed of the strip 3 is detected by a traveling speed sensor. The point of the time when the bend of the work rolls or the difference between the circumferential speed of the work rolls 42 and the traveling speed of the strip 3 exceeds the prescribed value is decided as the timing for replacing the work rolls 42. The failure and jump out of the work rolls of the tension leveler are thereby prevented.