METHOD FOR PREVENTING AXIAL MISALIGNMENT OF SLAG STOPPER FOR CLOSING TAP HOLE OF CONVERTER

摘要

PURPOSE:To prevent the leakage of molten slag by the misalignment of a nozzle stopper for closing a tap hole and the tap hole by turning back a converter while maintaining the specified intersection angle formed of the axis of the nozzle stopper and the axis of the tap hole at the end period of tapping with the converter. CONSTITUTION:The nozzle stopper 4 for opening and closing the tap hole B of the converter A is is attached to a nozzle supporting arm 3 and the molten steel in the converter is tapped by opening the stopper 4. The titled converter is turned back at the end period of tapping. The axial misalignment of the stopper 4 is detected by a converter turning back lever 16 at this time and a solenoid valve 14 for regulating flow rate provided to a hydraulic motor 13 for moving the arm 3 forward and backward is onloaded by the detection signal thereof to close an electric circuit consisting of a circuit 20 for detecting the angle of inclination of the arm, an amplifier 21 and the solenoid valve 14. As a result, the forward and backward moving speed is regulated to meet the angle of inclination of the arm 3 and the converter is turned back while the specified intersection angle formed of the axis of the stopper 4 and the axis of the tap hole B is maintained in such a manner. The leaking out of the molten slag in the converter into a ladle for the molten steel from the tap hole B is thus prevented.