Patent ID: 8210013

Claim:
A method for replacing at least one pair of rolls of a rolling mill stand during a downtime period in production between a stoppage of the rolling mill and its restarting, the method comprising the following steps: advancing a first car associated with a mill stand under consideration to an advanced position close to the mill stand; stopping rolling operations; actuating roll displacement means fitted to the first car to extract worn rolls fitted with chocks from the mill stand, by sliding along their respective axes, to place them on a replacement frame fitted on the car; retracting the first car to a retracted position away from the mill stand; moving a second car, equipped with an empty first exchange frame and a second exchange frame bearing new rolls without chocks, to a first position having the first exchange frame aligned with the replacement frame of the first car; actuating the roll displacement means of the first car to transfer the worn rolls fitted with chocks from the replacement frame to the first exchange frame of the second car; aligning the first exchange frame of the second car with a chock extraction device mounted on the second car; operating the chock extraction device to uncouple the chocks from ends of the worn rolls placed in the first exchange frame; aligning the second exchange frame of the second car with the chock extraction device; carrying out the aligning of the first exchange frame or the second exchange frame with the chock extraction device by actuating transposing means supporting the first and second exchange frames of the second car; operating the chock extraction device to couple the chocks to ends of the new rolls placed in the second exchange frame; moving the second car to a second position having the second exchange frame aligned with the replacement frame of the first car; actuating the roll displacement means to slide the new rolls fitted with chocks from the second exchange frame to the replacement frame; advancing the first car to the advanced position; actuating the roll displacement means to insert the new rolls fitted with chocks from the replacement frame into the associated mill stand; and restarting rolling operations.