Operating method for twin-roll casting machine, and side weir supporting device

Abstract

An operation to acquire a strip with less thickness even if arcuate worn steps are formed on side weirs is disclosed. During an operation of a twin-roll casting machine with arcuate worn steps developing on side weirs due to rotational sliding contact of chilled rolls, the thickness of a steel strip from a nip is reduced, and the center-to-center distance between the rolls is increased with the side weirs in contact with ends of the rolls being displaced upward. This prevents interference of outer peripheries of the rolls with boundary surfaces adjacent to the arcuate worn steps of the side weirs.

1 . A side weir supporting device comprising:
 pressing actuators which press side weirs against ends of chilled rolls in a twin-roll casting machine; and   position adjusting mechanisms which vertically displace said side weirs,   wherein the side weirs in contact with ends of the chilled rolls are displaced upward by said pressing actuators and said position adjusting mechanisms where a center-to-center distance between the chilled rolls is reduced to reduce the thickness of a strip from a nip between the rolls, and   the side weirs in contact with ends of the chilled rolls are displaced downward by said pressing actuators and said position adjusting mechanisms where a center-to-center distance between the chilled rolls is increased to increase the thickness of a strip from a nip between the rolls.   
     
     
         2 . The side weir supporting device as claimed in  claim 1 , wherein each of the position adjusting mechanisms includes a platform disposed close to the corresponding side weir, bearings which vertically guide the platform, and a ball screw which transmits vertical rotation of a servo motor as vertical displacement to the platform. 
     
     
         3 . The side weir supporting device as claimed in  claim 2 , wherein the pressing actuator is mounted on the platform such that a piston rod of the pressing actuator is positioned in parallel with a rotational axis of the chilled roll. 
     
     
         4 . The side weir supporting device as claimed in  claim 3 , wherein a tip of the piston rod is connected to the side weir.