PURPOSE: To cast a molten steel to a steel ingot which contains less impurities, has no macro segregation in the central part and has good quality by disposing plural stages of electric heating elements via a heat resistant material to the inside part of a casting mold for continuous casting of the molten steel and operating the heating elements from belong to above as the molten metal poured into the mold rises in the mold.
CONSTITUTION: The casting mold for casting the steel ingot is constituted of a bottom plate 1 and a cylindrical side wall 2. Plural stages of the cylindrical electric resistance heating elements 4, 5 of C-SiC, Al2O3-C, etc. are attached via an insulator 3 to the inside of the wall 2 and are so constructed that the elements can be discretely energized by a power source 7 to generate heat. A heat resistant material 6 having an electrical insulating material is disposed to the inside thereof. The molten steel is poured into the casting mold and as the molten steel surface rises, the elements 4, 5 are successively energized from the lower to upper part to heat the molten steel. The molten steel solidifies successively upward from the bottom plate 1 so that the solidified surface rises horizontally and that the formation of the macro segregation in the central part of the steel ingot is obviated. Since the boards for heat insulation and generation are not used, there is no intrusion of the impurities from the boards and the steel ingot 8 having the high quality is obtd.
HONDA NORIO
TOKUSHIGE SHOJI
