Abstract: A sealing device which comprises a refractory portion consisting of high-alumina material with an Al.sub.2 O.sub.3 content higher than 80%. The internal portion of the sealing device is made up of refractory cement with an Al.sub.2 O.sub.3 content higher than 80% which is cast and vibrated in a mould formed by a cylinder-shaped metallic part of the device and an internal fixed template. After the setting of the refractory cement, the internal templet is drawn out and the device, comprising a metallic and a refractory portion, is subjected to drying. This is effected at 150.degree. C.

Abstract: Method of and apparatus for treating and refining liquid metal alloys by direct current arc heating. On at least a part of the melt surface there is performed an electrolysis whereby the melt across a layer of liquid slag-electrolyte is connected as an anode or a cathode, and the connection with the other pole--cathode or anode--is effected by means of one or more direct current arcs. Depending upon the desired direction of the electrolysis process, it is possible to change the polarity of the metal melt or the slag-electrolyte. The apparatus for performing the method comprises a vessel equipped with a mechanism for pouring, a movable cover and movable electrodes. The centers of the electrodes are disposed symmetrically one to the other in a vertical plane. As a source of direct current there are used two or more rectifiers operating independently.

Abstract: A method for steelmaking with direct current in which, during melting in an arc furnace, the contact anodes are connected by contact to the iron material, and the electric arc is formed between the latter and the movable cathodes. After the contact anodes attain the slag, the further burning of the electric arc between the molten metal and the movable cathodes is effected so that the working ends of the contact anodes remain immersed in the slag.