PURPOSE: To reduce flying thickness change time by executing stepwise speed and screw down change without stopping screw-down at an arbitrary point during rolling.
CONSTITUTION: A titled device is formed of a change point pass timing indicating device 9 which operates and outputs the change point pass time of each command by thickness change commands, a flying screw down change command device 12 and a flying speed change command device 11. To change flying thickness with this device, deceleration is started in each stand at a certain point during the course of rolling, and when the rolling size change point comes to the 1st stand, the screw down of the 1st stand is operated while the rolling speed is being lowered. At this time, the speed of the 1st stand is so operated as to eliminate the tension fluctuation between the 1stW2nd stands and the speeds of the 2ndW5th stands are operated in the same manner as well. Next, when the rolling size change point comes to the 2nd stand, the screw down position of the 2nd stand and the speed of the 2ndW5th stands are operated.
OKAMOTO TAKESHI
UWAZUMI YOSHIAKI
MITSUBISHI ELECTRIC CORP