Abstract: A water cooled finger for a pre-heater of a furnace top holds metal materials of a required amount in a shaft installed at the furnace top for pre-heating metal materials by introducing exhaust gas at high temperature generated in the furnace into the shaft. The water cooled finger is formed of a pair of side aces, an upper plate and a lower plate. The upper plate is fixed to an upper plate of both of the side face portions. The lower plate is fixed to a lower plate of both of the side face portions. The water cooled finger is formed to be hollow as a whole by the side face, the upper plate and the lower plate. The water cooled finger satisfies at least one of the conditions of (A) a thickness of the upper plate is thicker than that of said lower plate, (B) the lower plate is formed to be R-bending processed portions at both ends thereof, and(C) the lower plate is curved outside.

Abstract: In an electric arc furnace cooling apparatus in which cooling water is made to flow into a plurality of water-cooled panels provided around side walls of a furnace body of an electric arc furnace to thereby cool the furnace body, a water collecting trough is provided in a platform mounted in the electric arc furnace to thereby collect waste water discharged from the water-cooled panels, and a water receiving trough is provided outside the platform to thereby receive waste water discharged from the water collecting trough.

Abstract: A cover with a spray cooling system for the main body of an electric furnace is of a double-layered structure with a hollow inner space in which are provided a plurality of spray nozzles such that cooling water sprayed therefrom will cool the cover. A water collecting box with one or more water outlets is attached to the outer circumferential side surface of the cover such that its bottom surface is below the bottom surface of the cover, and the interior of the box is connected to the hollow inner space of the cover such that the sprayed cooling water can be discharged without the use of a vacuum pump and does not cover the inner surface of the inner space to prevent uniform and efficient cooling of the cover.