HEATING METHOD FOR MOLTEN STEEL IN TUNDISH FOR CONTINUOUS CASTING MACHINE

摘要

PURPOSE:To heat stably and efficiently a molten steel without generating pinching in a bypass passage communicating with the inside of a tundish by generating the induction current of adequate current density by a coil in the molten steel in the bypass passage. CONSTITUTION:The bypass passage 8 communicating with the inside of the tundish 1 at an inlet 8a and an outlet 8b is provided in refractories 7 in a steel shell 6 on the side wall of the tundish 1 and an induction heater 2 inserted and built in with a primary induction coil 10 via a core 10a is provided into a through-hole 9 provided in the direction intersecting orthogonally with said passage. Electricity is conducted to the above-mentioned coil 10 to generate a magnetic field phi in the molten steel flowing from a nozzle position 3 for receiving the steel in the above-mentioned tundish toward an outflow part 4 and to generate induction current (i) in the molten steel so that the molten steel is heated by the Joule heat thereof. The supply electric power to the coil 10 is so controlled that the relation between the depth Hmm of the molten steel in the tundish and the current density DA/mm<2> of the induction current (i) satisfies the equation D<=0.45H+190.