Patent ID: 6253593
Filing Date: 2001-07-03
Classification: B21B

Abstract:
A piercer roll exchanging apparatus for use in a vertical piercing mill for replacing a pair of piercer rolls together with upper and lower cradles which accommodate the respective piercer rolls, and a spacer which adjusts the spacing between said upper and lower cradles, said paired piercer rolls being disposed one above the other and opposed to each other with respect to a pass line of a material to be rolled to piercing, the piercer roll exchanging apparatus comprising:a traveling carrier car operable to move between a traveling start position and a traveling end position close to a piercing mill body, anda cradle shifter carried on said traveling carrier car, said cradle shifter being operable for shifting said upper and lower cradles from said traveling end position to the interior of said piercing mill body, said cradle shifter being provided with a spacer clamp for clamping said spacer and for adjusting the vertical position of the spacer, and with a lower cradle clamp for clamping said lower cradle, said upper and lower cradles being stacked with said spacer being sandwiched therebetween and being movable horizontally and perpendicular to said pass line.