Abstract: For the purposes of better cooling and improving the starting conditions of a direct current arc furnace, there is provided a hearth electrode which comprises at least one metal bar passing through the hearth wall and which is cooled by at least one cooling duct which extends along the metal bar to the inner end thereof and opens into the interior of the furnace.

Abstract: A direct current arc furnace, includes a graphite cathode; and a container forming a hearth with a hearth base surface and having a container bottom acting as anode. The container bottom includes a supporting copper-plated sheet steel base consisting of a steel sheet and a copper plating plated on the steel sheet; electrical connection means extending through the steel sheet to contact the copper plating to supply an anode current to the copper plating; and a refractory brick lining having a graphite content above the copper-plated sheet steel base with the copper-plated layer adjacent the brick lining. In a preferred embodiment the graphite content in the brick lining decreases from the vicinity of the copper-plated sheet steel base to the vicinity of the hearth base surface.

Abstract: An arrangement for cooling vessel portions of a furnace (1) having a cooling box which is fitted into a wall or cover region to be cooled or which forms a wall or cover region and which, towards the furnace interior (6), includes a heat exchange plate (2) which is acted upon with cooling fluid through a plurality of spray nozzles (3). The heat exchange plate (2) is in the form of a composite plate comprising a steel plate (8) on the side towards the furnace interior (6) and a copper layer (9) on the side of the spray nozzles.

Abstract: In the method of producing steel by providing a vessel containing ferrous metal to be melted and passing electric current into the metal to melt the same by means of at least one electrode connected to an exterior source of electrical power, the improvement which comprises positioning an arc stabilizer material in proximity to the surface of the metal to be melted whereby as electric current is passed from the electrode into the metal the arc stabilizer material forms an arc adjuvant material which aids in the efficient operation of the electric arc, with the arc stabilizing material being an effective amount of a synthetic polymeric material having a low sulfur content.

Abstract: For the production of a reinforcing steel with a higher yield point and good weldability and toughness, microalloying elements are alloyed with the steel and their proportion represents 0.02 and 0.06% vanadium and 0.01 to 0.02% nitrogen, said proportions not being sufficient for achieving a higher yield point of at least 450 N/mm.sup.2. However, this is reached if the rolling stock undergoes controlled, but relatively limited cooling during or after rolling, in such a way that the compensating temperature of the steel reaches at least 700.degree. C. Due to the fact that the microalloying elements are only alloyed in small quantities and only relatively small water quantities are required, reinforcing steel can be economically produced. In addition, the process permits coiling in the case of wire rolling and can also be used on other rolled steel products.

Abstract: The electrode has a durable upper part and a consumable tip. A plurality of copper tubes extend through the upper part. The connection to the consumable tip is by means of an intermediate plate and a nipple, the latter containing ducts for the connection of the copper tubes. At the upper end of the electrode, the copper tubes are serially interconnected by tube bends and at their lower end by ducts in the nipple.

Abstract: A process for the production of molten crude iron and reduction gas is described wherein the molten iron and gas are formed in a smelting gasifier, to which is introduced at the upper portion thereof preheated sponge iron of particle size between 3 mm and 30 mm and coal to form a fluidized bed, and an oxygen-containing gas at the lower portion thereof, and controlling the ratio of oxygen-containing gas and coal to maintain a high temperature zone in the lower portion of the gasifier and a lower temperature zone in the upper portion thereof, the oxygen-containing gas being introduced substantially immediately above the resulting melt which is formed at the bottom of the gasifier.

Abstract: A fluid-cooled holder for the tip of an electrode of an electric arc smelting furnace, having a cylindrical holding portion which can be secured to an electrode support arm, a metal cooling system which is secured to the holding portion and which carries a screw-threaded portion for screwing on the electrode tip, and also having a tubular heat screen which is disposed around the cooling system at a spacing and which comprises a metal tube (11, 11a) which is electrically insulated with respect to the current-carrying cooling system (3, 3a) and which can be sufficiently cooled, by way of a refractory substance (17, 17a) between the cooling system and the metal tube, for the temperature of the metal tube to be kept to a value below the softening temperature of the material of the metal tube, when the holder is used in an electric arc smelting furnace.

Abstract: Continuous metal casting method, especially continuous steel casting method, in which the melt is set in rotation about the strand axis within the continuous casting mold and gas in the gaseous or liquid state is fed onto the bath surface excentrically to the mold axis and at an acute angle to the velocity vector of the rotatory movement. The rotatory movement of the melt is brought about substantially by the thrust of the gas directed at high velocity onto the bath surface. The apparatus for the practice of the method has circumferentially of the mold, at least 2 terminal fittings of gas feed lines, whose discharge orifices are so constructed that a rotatory movement of the melt is brought about substantially by the thrust of the gas directed at high velocity against the bath surface.

Abstract: An electric metallurgical furnace in which at least one row of the bricks that adjoin the annular flange the outer edge is displaced outwardly with respect to that of the bricks and the rows adjoining the annular flange are pressed by the flange on to the rows below.

Abstract: Melting furnace, especially an arc melting furnace, with a bottom vessel, in which the furnace wall contains at least one water cooling box welded of steel plate and disposed above the melt level, whose surface facing the furnace interior is provided with projections which facilitate the adhesion of a refractory protective layer formed on this surface, wherein the wall of the water cooling box, which faces the furnace interior, has a thickness of at least 15 mm, the projections are formed of profile irons, and a refractory composition applied beforehand serves as the refractory protective layer. Also, a seam or flange between the upper edge of the bottom vessel and the water cooling box so as to catch water flowing down the inside of the furnace and to pass it outwardly.

Abstract: An electrode for electric arc furnaces, in particular for production of iron and steel, comprising a liquid-cooled upper portion, which may be inserted into an electrode holder, a lower portion forming the electrode tip being detachably fastened to the upper portion, which upper portion contains a conduit system for the cooling liquid protected by a fire-proof material, by way of which conduit system the electric current of the arc electrode may also be conducted. Heat conducting projections covered by the fire-proof material are provided on the outer surface of the conduit system facing the furnace chamber, while an electromagnet for producing a magnetic field is disposed in the region of the fastening point of the electrode tip to cause the arc on the electrode tip to move.

Abstract: A liquid-cooled electrode for electric arc furnaces having a cover secured to an electrode supporting arm and containing cooled metal elements and having a core which can be axially displaced in the cover, into which core the electrode current can be conducted by way of a current conection. The current connection is disposed above the cover, while the cover is electrically insulated from the core and the insulation includes an insulating layer between the cover and the core. In addition, a device for producing a magnetic field is provided in the lower portion of the cover.

Abstract: An arc furnace which is supplied by means of alternating current by way of heavy-current conductors, with liftable electrode carrier arms, wherein the heavy-current conductors can be separated from each other by means of releasable electrical couplings.

Abstract: Melting furnace, especially an arc melting furnace, in which the furnace wall contains at least one water cooling box welded of steel plate and disposed above the melt level, whose surface facing the furnace interior is provided with projections which facilitate the adhesion of a refractory protective layer formed on this surface, wherein the wall of the water cooling box, which faces the furnace interior, has a thickness of at least 15 mm, the projections are formed of profile irons, and a refractory composition applied beforehand serves as the refractory protective layer.

Abstract: A method is provided for lengthening the life of electric arc furnace linings in the production of steel from scrap, while at the same time introducing sponge iron pellets to shorten the melting time. This is achieved by predetermining the increase in power at the arc-molten bath interface upon introduction of the sponge iron and automatically reducing the power factor in the circuits feeding the electrodes according to the predetermination, upon each introduction of sponge iron.