| 摘要 |
PROBLEM TO BE SOLVED: To provide a rolling reduction method of a casting piece capable of improving quality of the casting piece, and capable of improving a yield, by sufficiently exhibiting rolling reduction performance of a rolling reduction device, in the rolling reduction method of the casting piece by using the rolling reduction device liftable in the vertical direction in a vertical type continuous casting machine.SOLUTION: A method is provided for roll-reducing a casting piece cast by a vertical type continuous casting machine, comprises a rolling reduction roll for roll-reducing the casting piece, and uses a rolling reduction device liftable in the vertical direction by driving force of a lifting motor and driving the draft roll by a roll driving motor, applies a vertical characteristic to control of a rotating speed of the lifting motor, and when the rolling reduction device is lifted at a command speed to roll-reduce the casting piece, reduces the rotating speed of the lifting motor when torque of the lifting motor exceeds reference torque being torque when rolling reduction of the casting piece is not performed, and increases the rotating speed of the lifting motor when the torque of the lifting motor falls below the reference torque. |
