HYDRAULIC ROLLING REDUCTION TYPE ROLLING MILL

摘要

PROBLEM TO BE SOLVED: To keep the height of a pass line to be constant, to enable the fine adjustment of a rolling reduction quantity and to improve the dimensional precision of a rolled material by using a two-way discharging fixed volume or variable volume hydraulic pump directly connected with a motor as the hydraulic press source and executing synchronous roll-down and/or synchronous roll-up with a hybrid actuator. SOLUTION: The rolling-reduction device 20 is provided with the hybrid actuator (driving source integral type hydraulic actuator) and arranged to each of the upper and the lower roll chocks 2, 4 at the right and the left sides in a rolling mill body l so that it is possible to execute the roll-down during rolling. In this rollingreduction device 20, a single-rod type double acting cylinder fixed to the rolling-mill body 1 is incorporated, and the two-way discharging type hydraulic pump directly connected with the motor, a liquid quantity difference absorbing circuit in the head side and the rod side at the time of working a cylinder and close type tanks for compressed gas and working liquid, are integrated. At the time of rolling, the feedback of displacing information of the cylinder rod is executed with a linear scale and this information is compared with an input positional command, and the input of the motor in the hydraulic pump is controlled to adjust the rolling reduction quantity.