METHOD FOR CHANGING INGOT WIDTH

摘要

PURPOSE:To absorb effectively the error for a target change quantity arising from the difference between the taper quantity in the stage of starting the width change on the short side of a casting mold under continuous casting and the target taper quantity at the end of the width change by providing a parallel moving period when the speed at the top and bottom ends of the short side are made the same during the time of the shift from the previous tilting period to the post tilting period. CONSTITUTION:The movement of the short side 1a of the casting mold is segmented to the previous tilting period when the short side is successively tilted toward the central side of the mold and the post tilting period when the short side is gradually tilted toward the counter central side of the mold in the stage of expanding or reducing the width of the ingot 4 by moving the side 1a during continuous casting. The speed increase rate alpha of the horizontal moving speed at the top and bottom ends of the short side in each period is prelimi narily determined with the permissible resistance force against the shell deformation as a parameter and the difference DELTAV in the moving speed of the top and bottom ends is deter mined by the equation. The error for the target width change quantity arising from the difference in each target taper quantity in the stage of starting the width change and at the end of the width change is absorbed by providing the parallel moving period during the time of the shift from the previous tilting period to the post tilting period in the case of changing the width while maintaining the specified speed increase rate alpha and speed differ ence DELTAV during said period, by which the exact width change of the ingot is executed in the min. time.