Abstract: In a charging material preheater for a metallurgical smelting plant having a shaft (5) which has closure members (7, 8) which are pivotable by a control member (6) and which include fingers (9, 10) which are arranged parallel and at a spacing relative to each other, the fingers (9, 10) of a closure member (7, 8) are mounted with a central portion in a first rotary mounting (12, 13) and in a second rotary mounting (21, 22) of the frame structure (2) with an outer portion which is passed outwardly through an opening (14, 15) in the shaft wall, by way of an elbow lever mechanism (16, 17), and lever arms (18, 19) of at least two elbow lever mechanisms are connected together by a connecting member (23) which is pivotably engaged by a control member (6) which is supported in a third rotary mounting (26, 27) of the frame structure (2).

Abstract: Apparatus for supplying a molten metal (5) in a metallurgical vessel (3) with a gas and fine-grain solid materials comprising a water-cooled first lance (117) for the supply of the gas and a second lance (119) for the supply of the solid materials. The supply of the solid materials is effected in such a way that, after leaving the outlet opening of the second lance (119), the materials are deflected by the gas (127) issuing from the outlet opening of the first lance (117), and are fed with said gas to the molten metal (5). The lances are inserted through the side wall of the vessel (3).

Abstract: In a smelting unit comprising an arc furnace and at least one shaft-like charging material preheater which is arranged laterally on the furnace vessel of the arc furnace and the interior of which is connected in a region adjoining its bottom to the interior of the furnace vessel by way of a connecting zone, and in addition burners open in the lower region of the charging material preheater, in a sump mode of operation after the tapping step, of the amount of charging material which is required for the next bath of molten material, a part thereof is charged directly into the furnace vessel in order to reduce the smelting time. That part of the charging material is preheated in a preheating chamber which is connected downstream of the charging material preheater.

Abstract: In a process for at least temporarily simultaneously subjecting a molten metal (5) in a metallurgical vessel (3) to the action of a gas and fine-grain solid materials, with a water-cooled first lance (17) for supplying the gas, in accordance with the invention the solid materials are supplied in the form of a conveyor stream (27) by way of a second lance (19). The solid materials are supplied in such a way that, after leaving the outlet opening (25) of the second lance (19), they are deflected by the gas (29) issuing from the outlet opening (23) of the first lance (17) and are supplied with said gas to the molten metal (5).

Abstract: A furnace vessel (301) of a metallurgical furnace, in particular an electric arc furnace, in which the tap hole (305) is arranged within a lower vessel (303) which is oval or circular in plan view, in the vicinity of the wall of the vessel, and the upper vessel (309), above the tap hole (305), includes a vessel portion (320) which is displaced or is displaceable relative to the lower vessel towards the center of the vessel and in which there is provided a maintenance opening (327) for the tap hole (305) (FIG. 11).

Abstract: In an electric arc furnace having a fluid-cooled electrode support arm which is provided with an electrode holding means, the outside of the electrode support arm is plated with cooper and the electrode holding means is electrically insulated with respect to the support arm, by way of which the electrode current is carried to a contact jaw that bears against the electrode. In an electric arc furnace with for example three parallel electrode support arms the electrode current is taken partly by way of a heavy-current tube and partly by way of the electrode support arm in order to balance the different reactance in relation to the two other electrode support arms. In order to eliminate reactance asymmetry, a reactance loop is provided in at least one heavy-current conductor between the transformer of the electric arc furnace and the associated electrode support arm.

Abstract: For the purposes of charging an electric arc furnace the cover (3) of the furnace is lifted somewhat and, being held by a cover carrier mechanism (10, 11), pivoted to the side. The cover carrier mechanism (10, 11) is connected to a portal structure (13) which is rotatable about a vertical axis. At the same time horizontal electrode support arms (5, 6, 7), with the electrodes secured to the free ends thereof, are pivoted to the side. The electrode support arms are secured to vertically displaceable lift columns (19, 20, 21). The lift columns are arranged in one plane and have roller guides (15a, 15b; 16a, 16b) which are disposed in two horizontal planes. The rollers of each pair (15a, 15b . . . ) are so inclined that their axes of rotation include an angle of between 90.degree. and 160.degree.. In that way moments about vertical axes upon pivotal movement of the arrangement and in operation of the furnace can be carried.

Abstract: For the purposes of introducing filling material which is capable of flow into a tap hole which is disposed in the edge region of the bottom of a metallurgical vessel, in particular a smelting furnace, there is provided a filling pipe which is secured to an arm which is pivotable about a pivot means mounted to the wall of the vessel. The pipe can be pivoted from a position outside the vessel through an opening in the wall of the vessel into a filling position in which the intake opening of the pipe is in communication with a container for supplying the filling material and the discharge opening of the pipe is in opposite relationship to the tap hole. The pipe is of a circularly bent configuration around the pivot axis of the arm so that the opening in the wall of the vessel can be kept small.

Abstract: An arc furnace having a space for accommodating charging material, said space being disposed on one side of the furnace vessel and communicating with the interior of the furnace vessel and being disposed at least partly in the region of radiation of the arc of at least one arc electrode. The arc electrode is movable towards and away from the charging material accommodating space, and thereby permits better utilization of the radiant heat generated by the arc.

Abstract: In a fluid-cooled clamp member (1) of a composite electrode (2) of an electric arc furnace, disposed in the flow path (13) for the coolant is a shut-off device (14) which is biassed in the closure direction, having an actuating member (15) by means of which the shut-off device (14) is put into the open condition in opposition to the biassing force, when a replaceable lower portion (2) of the composite electrode, which is subject to burning away, is screwed on. In the event of fracture of the lower portion in the region of the nipple (5), the flow path (13) is closed off by the actuating member (15) being released. The screwthreaded nipple is additionally protected by means of a protective cap which is screwed on to the screwthreaded nipple, the cap having an external screwthread corresponding to the internal screwthread of the lower portion (2).

Abstract: Electric arc furnace, having a tapping hole (2) in the bottom of the vessel or in the bottom of a part (1) of the vessel, which projects in a bay window-like manner, and a closure arrangement (3) for the tapping hole (2), comprising a closure plate (4) which is movable from a closure position of closing the tapping hole from the outside into an open position of opening the tapping hole, by means of a first lever (6) which is pivotally mounted to the outside of the vessel (pivot axis 11) and which is pivotal by a drive means (14), whereby the closure plate (4) is mounted to an arm (5) which is connected rotatably (rotary axis 8) to the first pivotal lever (6) and which is guided by means of a second pivotal lever (7) which at a spacing from the first lever (6) on the one hand is pivotally connected to the outside of the vessel (pivot axis 12) and on the other hand is connected rotatably (rotary axis 9) to the arm (5).

Abstract: In a furnace charge preheater, especially one for scrap metal, in the form of a bucket whose bottom contains at least two outswinging half-shells, the bucket bottom when in the closed state is formed of a central part and at least one ring while the inner margin of the ring overlaps the margin of the central part and the margin of the central part is situated at a distance below the inner margin of the ring thus forming an annular gap. In this manner a more uniform flow of the hot gas through the preheater is assured. Furthermore, if the annular gap between the bucket bottom and the bucket wall is sealed up, the chamber on which the charge preheater is placed when the charge is preheated, can be made smaller.

Abstract: A nozzle assembly constituting a burner or blowing nozzle includes, in the region of the discharge opening thereof, a piston-like member which is displaceable by an actuating means into a position of blocking off the discharge opening thereby to prevent same from becoming clogged by slag or metal splashed thereon. When the assembly is mounted in the wall of a metallurgical furnace, the piston-like member may also be adapted to close off the opening in the wall, which communicates with the nozzle assembly, in order also to keep the wall opening open. At least a part of the piston-like member may be caused to oscillate or at least the part thereof which is towards the interior of the furnace may comprise or be coated with a scale-resistant material or may be coated with a material that is difficult to wet.

Abstract: Apparatus for disconnecting a residual portion of a consumed graphite electrode from a permanent electrode which has been lifted out of an electric furnace and which may still be hot, and for connecting a fresh graphite electrode portion to the permanent electrode, comprises a housing for surrounding the electrode assembly in the region of a screw nipple on the permanent electrode. Disposed in the upper region of the housing is an upper clamping means for holding the permanent electrode, while disposed in the lower region of the housing is a lower clamping means which can produce a screwing movement for unscrewing and screwing on the graphite electrode portion. The housing is of a double-walled construction to provide for water cooling thereof.

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.