Abstract: According to the present invention, there is provided a direct current electric furnace for melting metal capable of melting scraps rapidly and also capable of diminishing cold and hot spots formed on the furnace wall, wherein the direct current electric furnace is provided with a single top electrode, a plurality of furnace bottom electrodes, or a plurality of electrode units obtained by dividing a multitude of furnace bottom electrodes of a small diameter into plural units, and electric current controlling thyristor circuits for controlling each individually electric currents flowing through the plural furnace bottom electrodes or electrode units. The electric current controlling thyristor circuits may be substituted by thyristor circuits for controlling electric currents for each of plural groups obtained by dividing the above plural furnace bottom electrodes or the above many furnace bottom electrodes or the above plural electrode units into the plural groups.

Abstract: Electromagnetically stirring a molten metal in a continuously casting mold, wherein a plurality of linear motor type stirrer units each having a square shape each side of which is smaller than the height dimension of the mold are arranged in parallel along the long sides of the mold in such a manner that they are adapted to change the attached posture by 90.degree., so as changing the direction of a stirring flow of the molten steel into a given direction. As a result the surface defect is removed and the quality of the solidification structure is improved, and the application range of the kinds of the steels to be cast can be enlarged.

Abstract: The present invention relates to a technique or method for stirring molten steel, wherein molten steel charged in a mold for continuous casting is circulated in a smooth flow in order to promote the degassing of the steel as well as to prevent the formation of surface defects on the cast steel. In order to carry out such desirable stirring, the present invention provides for a plurality of electromagnetic stirrers (capable of applying different magnetic field intensities) to be arranged along both long side walls of the casting mold so that the circulating flow of the molten steel can be accelerated or decelerated (depending upon its position) to form a smooth flow.