Abstract: A furnace assembly for a metal-making process, including: an electric arc furnace configured for flat bath operation and having a bottom, and an electromagnetic stirrer configured to be arranged underneath the bottom of the electric arc furnace to enable stirring of molten metal in the electric arc furnace.

Abstract: Disclosed is a control system for a melting process in an electric arc furnace for melting a metallic material that minimizes desired process properties such as the melting time or the total power consumption of the melting process. The system includes a processing unit adapted for receiving or collecting measured data of at least one process variable, determining the current state of the process, performing an optimization of the melting process, determining a process input based on the result of the optimization, and controlling the melting process with the process input. A method is also presented herein.

Abstract: An electrode joining apparatus for joining a fixed electrode and a free electrode including an electrode holder configured to receive the fixed electrode and a torque device positioned above the electrode holder. The torque device is configured to grip and spin the free electrode to join the free electrode to the fixed electrode. A force sensor is coupled to the torque device. The torque device is configured to apply a force on the force sensor when the torque device engages the free electrode, the force sensor configured to detect a signal representative of the force applied by the torque device on the free electrode. The feedback force signal can be used to determine the torque applied to the free electrode by the torque device to help ensure that a proper joint is formed between the free electrode and the fixed electrode.

Abstract: This reduction processing apparatus for a steel-making slag that continuously performs reduction processing to a hot steel-making slag by using an electric furnace includes: a slag-supplying container that charges the hot steel-making slag into the electric furnace; an electrode that is provided at the electric furnace and heats a molten slag layer on a molten iron produced by reducing the hot steel-making slag; an auxiliary-raw-material supplying unit that supplies an auxiliary-raw-material including a reducing agent to the molten slag layer; and a tilting unit that tilts the slag-supplying container and adjusts a charging amount of the hot steel-making slag to the electric furnace.

Abstract: A sensor system for monitoring and controlling the performance of the bottom electrode and the deflection of an electric arc in an electric steel making furnace includes an organized matrix of anode pins interspersed with refractory material and extending toward an electrically conductive plate secured to distal ends of the anode pins. A sensing device includes two temperature sensors at spaced apart locations along each of a distributed select group of anode pins for providing corresponding electrical signals and a current sensor responsive to electrical current flowing through the anode pins of the distributed select group of anode pins for providing a corresponding electrical signal. A controller responsive to the electrical signals derived at the anode pins of the select group operates the power supply and a display for monitoring the electrical performance of the elongated anode pins for heating by the electric arc in the furnace.

Abstract: An agitator for applying an alternating field to a melting furnace main body in order to melt a row material to form a melt includes a plurality of magnets, which are arranged so that magnetic lines of force emitted from one of the magnets pass through the melt in the melting furnace main body and return to another magnet, the magnets being fixed to an inclined surface which is inclined by an angle with respect to a horizontal surface, and being rotatable around an axis substantially perpendicular to the inclined surface.

Abstract: An AC arc furnace has a plurality of electrodes arranged inside a furnace chamber enclosed by a shell. Each electrode is electrically connected to an electrode power source in series through corresponding auxiliary electromagnetic coils. The electromagnetic coils are arranged around the furnace shell in a pre-defined geometric pattern proximate the corresponding electrodes so that when each of the electrodes receives power from the power source and generates an arc inside the furnace, external magnetic fields are generated by the corresponding series connectedelectromagnetic coils. The external magnetic fields penetrate the shell to control deflection of the arcs caused by internal magnetic fields.

Abstract: An AC arc furnace has a plurality of electrodes arranged inside a furnace chamber enclosed by a shell. Each electrode is electrically connected to an electrode power source in series through corresponding auxiliary electromagnetic coils. The electromagnetic coils are arranged around the furnace shell in a pre-defined geometric pattern proximate the corresponding electrodes so that when each of the electrodes receives power from the power source and generates an arc inside the furnace, external magnetic fields are generated by the corresponding series connectedelectromagnetic coils. The external magnetic fields penetrate the shell to control deflection of the arcs caused by internal magnetic fields.

Abstract: An arc control apparatus for a DC arc furnace provides an additional magnetic field which prevents a discharged arc from shifting outward at an arc generating point due to the influences of a magnetic field generated by a feeder circuit, thus directing the arc discharge vertically downward. The arc control apparatus includes an arc furnace in which an object to be melted is disposed. A movable electrode is disposed in the arc furnace for movement relative to the object. A feeder circuit including a power supply and a feeding conductor is connected to the movable electrode and the arc furnace for supplying a voltage therebetween from the power supply through the feeding conductor to generate an arc whereby the object is dissolved. An auxiliary coil is disposed outside and in the vicinity of the arc furnace and connected to the feeder circuit for generating a counter magnetic field in a direction to cancel a magnetic field which is generated at a point of generation of the arc by means of the feeder circuit.

Abstract: A direct current electric arc furnace for melting or heating raw material or molten material. The furnace includes a refractory lined vessel for holding raw or molten material in its interior. The furnace includes at least a first top electrode. The first top electrode enters the vessel interior above the raw or molten material. The furnace includes at least a first bottom electrode mounted in the bottom of the vessel and in electrical contact with the raw or molten material in the vessel. The furnace also includes an electrical power supply mechanism which electrically connects to the top electrode and the bottom electrode in order to input electrical energy into the material through the top and bottom electrodes in the form of an arc. The bottom electrode has an opposite electrical polarity to the electrical polarity of the top electrode. The furnace includes a mechanism for stirring the molten material in the vessel and guiding the arc in the vessel.

Abstract: The furnace vessel for a DC arc furnace has a thermostable wall which preferably consists, in the region situated above the slag line (S), of a plurality of water-cooled wall segments (1) made from steel. These wall segments are fastened to a support structure (13-18). At least one of the wall segments (3) consists of nonmagnetic steel or copper and is preferably arranged on the side of the furnace vessel (5) opposite the power supply device (7). In this way, the influence of the high-current lines which extend below or beside the furnace vessel and cause a deflection of the arc can be compensated.The effect of this nonmagnetic wall segment can be partially or virtually entirely cancelled by a trimming plate (19) which is detachably fastened from the outside to the nonmagnetic wall segment (3), in order in this way to achieve optimum trimming of the deflection of the arc.

Abstract: A direct current electric arc furnace for melting metal, which furnace includes a furnace vessel having a lower vessel part lined with a refractory material and a metal upper vessel part through which a cooling agent can flow. A cover is adapted and arranged to close the furnace vessel. Electric current is fed to the furnace, by an arrangement including a main electrode extending into the furnace vessel through the cover, a bottom electrode located at the bottom of the lower vessel part, and feed lines that connect the electrodes to a direct current source. The feed lines include at least two current feeds connected to the bottom electrode, each current feed having a line segment parallel to a main axis of the main electrode and a shield for at least partially magnetically shielding the upper vessel part at an arc level from magnetic fields generated by the line segments parallel to the main axis.

Abstract: Direct-current smelting furnace with control of deflection of the electric arc, which comprises an upper electrode (13) with relative return-flow lines and a plurality of bottom electrodes (11) positioned on the hearth of the furnace (12) and arranged in two or more assemblies, each assembly having its own controlled supply line connected to its own transformer (16), there being included downstream of each transformer (16) its own thyristor rectifier assembly (17) associated with its own means to control voltage (26), current (24) and firing angle (23), at least the lines supplying the bottom conductors (32) being at least partly screened in the vicinity of the melting furnace (12)

Abstract: In a direct-current arc furnace having a bottom contact (3) which has a large area, electromagnetically produced bath agitations are influenced by an electromagnet (9) disposed underneath the vessel bottom (4) such that the natural flow in the melt bath, caused by the current flow in the melt, is reversed in direction. In this way the stability of the bottom electrode (3) is substantially increased. The electromagnet (9) is preferably integrated into the electric supply system of the furnace and serves as a smoothing choke.

Abstract: A direct current arc furnace has a furnace vessel which is surrounded by a metal shell having at least one electrode connected as a cathode, and at least one bottom contact. The bottom of the furnace consists of a lining layer which possesses electrically conducting bricks or the like, which lining layer lies on a contact plate covering most of the bottom. The contact plate forms the bottom contact connected as the anode and lies on a bottom plate. The bottom plate is equipped with a plurality of connection fittings which pass through openings in the bottom plate and are connected via electric wires to a current supplying device provided next to the furnace. For the internal deflection of the arc, at least one section of the lining layer is composed of a material which possesses a lower electrical conductivity than the lining layer in another section which is circumferentially spaced from the one section so as to form circumferentially spaced zones of varying conductivity.

Abstract: An improved arc furnace regulator employs neural circuits connected in a multi-layer network configuration with various weighted relationships between the successive layers which are automatically changed over time as a function of an error signal by means of the back-propagation method so that the regulator gradually improves its control algorithm as a result of accumulated experience. The network is implemented in software which can be developed and run on a PC with extra co-computing capability for greater execution speed. A second trainable neural network which emulates the arc furnace is used to develop the error signal, and is trained in mutually exclusive time periods with the training of the regular network.

Abstract: A direct current electric furnace for melting metal raw material, especially scrap iron, comprises two consumable electrodes separated from one another and both offset laterally on the side of the median plane P1 of the vessel turned towards the current source. At least four fixed electrodes are distributed on either side of the median plane and arranged substantially at the vertices of a regular polygon symmetrical with respect to the median plane and placed between the vertical projections of the consumable electrodes, the conductors of the electrodes placed towards the source being orientated directly towards the latter, parallel to the conductors of the consumable electrodes and the conductors of the electrodes placed on the side opposite to the source each comprising a first branch passing around the vertical projection of the corresponding consumable electrode and a second branch orientated towards the source parallel to the conductors connected to the consumable electrodes.

Abstract: A direct current electric arc furnace comprises a main body, a moving electrode attached at the center of a roof of the furnace which generates an arc under the moving electrode, a bottom electrode attached at the center of the bottom, conductors which are connected to the bottom electrode, so that the deviation of the arc caused by a magnetic field originated at the outside of the main body is cancelled by another magnetic field caused by the conductors when electric currents are fed to the conductors and means of feeding direct currents to the conductors.

Abstract: In a direct-current arc furnace having a bottom electrode (2), electromagnetically and/or chemically induced bath agitations are substantially eliminated by an electromagnet (9) arranged under the vessel bottom (7). In this way the stability of the bottom electrode (2) is considerably increased. The electromagnet (9) is preferably integrated into the electrical supply of the furnace and serves as a smoothing choke.

Abstract: An electric-arc device has two aligned electrodes separated by an arc gap. The position of an electric arc in the arc gap is stabilized by using at least two coils, each made as a rectangular loop and bent around a cylindric surface. The coils are mounted around the electrodes such that their arcuate sides form two respective circumferences whose centers lie on a line parallel to the axis of the electrodes. The length of the straight side of each coil is no less than the length of the arc gap. The coils are connected to a power supply such that currents flowing along the adjacent straight sides of the neighboring coils are oppositely directed. These opposing currents induce a magnetic field into the arc gap which controls the location of the electric arc.

Abstract: A set of conductors comprising at least two return conductors (5) connected to a hearth electrode (3) is arranged along the outer face (11) of the furnace vessel in direct proximity thereto, and the profile and orientation of at least two conductors of the set are determined, in order, as a result of the passage of a direct current of controlled intensity, to generate magnetic fields of which the mutual deflection effects on the arcs, taking into account all the magnetic influences exerted by the other conductors and the various parts of the installation during operation, are such that the arcs are directed towards a specific zone of the molten-metal bath.

Abstract: Stabilizing the arc in an electric arc furnace is achieved by using a method and apparatus for applying a magnetic field parallel to the arc between the furnace electrodes. The magnetic field strength applied by the invention should exceed (h.mu.oI)/(2.pi..sup.2 a.sup.2) where h is the distance between the electrodes, a is the radius of the arc, I is the current between the electrodes and .mu.o is the permeability of free space. The magnetic field may be induced by any means not susceptible to the heat of the furnace, such as a coaxially positioned induction coil or by inducing a magnetic field in an open magnetic ring the ends of which form the furnace electrodes.

Abstract: Electric arc apparatus and an associated method are provided. Pairs of aligned cooperating coils are positioned on opposed sides of a crucible. In a preferred embodiment, three such pairs which overlap each other are employed so as to sequentially generate magnetic fields so as to provide a uniform magnetic field which will rotate the arc between the electrode and the crucible interior in a first direction. The arc rotation may be reversed. It is preferred that the maximum magnetic field created by each pair of coils be out of time phase with respect to the other coil's magnetic field. This apparatus and the associated method serve to resist undesired irregularities in the ingot exterior surface which irregularities would require subsequent treatment and result in loss of metal.

Abstract: The metallurgical vessel comprises a continuous wall and a bottom plate and such vessel constitutes a mold for electrically remelting an electrode by resistance heating of an electrically conductive slag bath. The metallurgical vessel further comprises solenoids for generating an electromagnetic field which is controlled by control means operatively connected to a reference signal generator and to magnetic measuring means like Hall generators preferably arranged tangentially relative to the vessel.

Abstract: A DC electric arc furnace utilizing a magnetic field stabilized electric arc. A DC magnetic field is employed to cause rotation and angular deflection of the electric arc about the surface of the melt. In one embodiment the DC magnetic field is induced by a field coil. In an alternate embodiment a specially shaped electrical insulating member can be positioned in the melt so that the flow of arc current through the melt creates a magnetic field which is used to cause arc rotation. In a further embodiment a plurality of coil sets are located about the periphery of the furnace are used in conjunction with current reversing and current sequencing means to create a rotating DC magnetic field which is used to rotate the arc. A ceramic electric insulator can also be supplied in the chamber of the furnace to prevent arc fixation in the region wherein the DC magnetic field is substantially parallel to the flow of arc current.

Abstract: A DC arc furnace has shielding between the arc and its power lines preventing or retarding the magnetic field created by the power lines from deflecting the arc.