LADLE NOZZLE CONTROL METHOD AND SYSTEM

PROBLEM TO BE SOLVED: To provide a ladle nozzle control method which can reduce the number of operating times of a nozzle, and is satisfactory in the surface control of molten metal. SOLUTION: A deviation is determined between a weight target value and a weight actual value of a tundish 9, with the determined deviation compared to a nozzle position correction quantity (determination graph 16) that is set preliminarily stepwise relative to deviations only. When the deviation is in a dead zone around the weight target value, a zero nozzle position correction quantity is outputted so that no nozzle 10 is moved. When the deviation enters in a first control region beyond the dead zone, a first nozzle position correction quantity is outputted that is larger than zero, with the nozzle 10 moved based on the first nozzle position correction quantity. When the deviation further becomes greater to enter a second control region beyond the first control region, a second nozzle position correction quantity is outputted that is larger than the first, with the nozzle 10 moved based on the second nozzle position correction quantity. COPYRIGHT: (C)2010,JPO&INPIT