MOLTEN METAL LEVEL POSITION MEASURING METHOD FOR DUAL-DRUM TYPE CONTINUOUS CASTING

PURPOSE: To accurately detect the position of a molten metal level even when the surface of a drum reflects a light emitted from the high-temperature molten metal by using a polarizing lens in the case of measuring the molten metal level position in a dual-drum type continuous casting, and forming the image of an image receiver by the transmitted light of the lens. CONSTITUTION: A molten metal level position is measured based on the image of a boundary 8 between the molten metal 1, the image of which is received by a CCD type image receiver 10 and the surfaces of the drums 2, 2' of a dual-drum type continuous casting machine. In the case of measuring the level position, a polarizing lens is used to form the image of the receiver 10 by the transmitted light of the lens. When the radioactive ray of the sum generated from the surfaces of the drums 2, 2' is passed through the lens, the ray from the metal 1 reflected on the surfaces of the drums is cut off by the lens. Accordingly, the image of the receiver 10 becomes a tint image corresponding to σT1 (where T1 is the absolute temperature of the molten metal) of the metal 1, the images of the drums 2, 2' become dark color images corresponding to σT24 (where T2 is the absolute temperature of the drum), and hence the boundary is clarified.