UPGRADING OF THE DRUM LOCKING DEVICE OF A PIERCER

The upgraded drum locking device has integral drum locking blocks and a float screw rod, with the antivibration performance improved and the thread clearance eliminated. With the upgraded locking device the axial force of the screw rod is reduced by half when roiling, Which makes the drum locked more reliably.Two years' practice shows that the upgraded drum locking device of a piercer can fully meet the requirements of a twice piercing process and is worth wide application.