Abstract: A cylindrical workpiece cutting apparatus is provided with a holder in which a metal made cylindrical workpiece is mounted on an outer periphery of the holder and which is adapted to hold the workpiece over an entire length of the workpiece; annular recesses formed on the outer periphery of the holder at a predetermined interval; a laser outputting part provided at a position opposed to the holder and adapted to output laser beam to the workpiece; and a cover portion provided on surfaces of the annular recesses and adapted to prevent attachment of metal particles which are scattered during cutting the workpiece by the laser beam.

Abstract: A sealing device is arranged around a rod electrode extending vertically through an aperture made in the ceiling of an arc furnace and being vertically movable inside the furnace to prevent the access of gases from the furnace through the aperture to the atmosphere, and on the other hand to prevent air from flowing from the atmosphere into the furnace. The sealing device comprises a gas distribution chamber provided with an inlet channel for feeding essentially passive gas, such as nitrogen or air, into the gas distribution chamber. The sealing device also includes a slit nozzle encasing the electrode, through which nozzle a gas jet is arranged to be discharged from the gas distribution chamber towards the electrode in a direction that is at an angle with respect to the horizontal plane and has a slightly upwards inclined orientation, and that is, with respect to the furnace interior, pointed outwardly, so that the sealing is carried out owing to the effect of the created stagnation pressure.

Abstract: Metallurgical reactors having cooling capability and electrode feed capability are disclosed. The reactors may include a shell having a sidewall and a bottom, where the shell is adapted to contain a molten material. The reactors may include at least one consumable electrode protruding through an opening of the shell and into the molten material. The reactors may include a current contact clamp configured to conduct operating current to the electrode, where the current clamp is in contact with the electrode, and where the current clamp comprises at least one internal channel, wherein the internal channel is configured to circulate a cooling medium. The reactors may include an electric isolation ring disposed between the electrode and the opening of the shell, wherein the electric isolation ring is configured to sealingly engage the electrode and the opening so as to restrict flow of the molten material out of the shell.

Abstract: In an embodiment, an electrode holder assembly (100) includes a current delivery base (105) having an interface (204) sufficiently designed to distribute an electrical current; a buss plate (200) sufficiently designed to provide the electrical current to the current delivery base (105); a shoe-ring assembly having: a plurality of electrical shoes (120), wherein the electrical current from the current delivery base (105) is distributed to the plurality of electrical shoes (120) for distribution to an electrode (400); a plurality of dual stroke cylinders (190); and a mounting ring (220); and a hydraulic assembly (300) including a grip ring (310) having an opening sufficiently designed to engage an outer surface of the electrode (400); a pressurizing cylinder (320) sufficiently designed to constrict and relax the grip ring (310); and at least one dual stroke cylinder (330) sufficiently designed to control horizontal movement of the grip ring (310) and the electrode (400).

Abstract: A lifting apparatus for transporting a carbon based electrode having a threaded male end. The apparatus includes a casing having a top end and a bottom end. The casing defines an electrode aperture from the bottom end shaped to accept the threaded male end of the carbon based electrode to secure the lifting apparatus to the electrode. An attachment aperture is positioned in the top end while an attachment element is positioned in the attachment aperture and operatively engaging the top end of the casing. The attachment element is positioned to accept engagement from a crane or other powered lifting device, while the lifting apparatus is preferably manually attachable to the electrode.

Abstract: An electrode column and a method of determining the length of the electrode in it in an active furnace. The column is a Söderberg column including a mantel in which the electrode is movable in an axial direction by lower and upper slipping clamps which are movable relatively to each other by slipping cylinders. The method includes the steps of moving, with the slip clamps, the electrode in a downslip relatively to the mantel with the slipping cylinders and gravity and measuring the force required to move the electrode with only the upper slipping clamp against predetermined reaction forces acting against movement of the electrode and computing these parameters to determine the mass and so the length of the electrode relatively to the theoretical mass of the undamaged electrode at the time of movement.

Abstract: A system is disclosed for lowering (“slipping”) and/or raising (“back slipping”) electrodes relative to an electrode column. The system includes an electrode column having at least one slipping sleeve and a power clamp, each of which apply a radial clamping force to the electrode. The magnitudes of the clamping forces are selected such that application of a downwardly directed axial force on the one or more slipping sleeves, in combination with the weight of the electrode, are sufficient to overcome the resistive force of the power clamp, resulting in downward movement of the electrode without release of the clamping forces. Electrode columns having two movable slipping sleeves are also capable of raising the electrode relative to the furnace without release of the clamping forces.

Abstract: A current-conducting arm for conducting a current from at least one cable supports to an electrode in an electric arc furnace comprising an arm housing having a U-shaped base channel member and a U-shaped top channel member. Both channel members have a first and second wall, with the top channel member being inverted such that the first wall of the top channel member can be joined with the first wall of the base channel member, and the second wall of the top channel member can be joined with the second wall of the base channel member. The arm housing therefore has four annular corners to improve the conduction of current through the arm housing to the electrode. The invention further includes a spring assembly used to provide to aid an electrode holder in clamping the electrode. Moreover, a laser pointer is included for guiding the positioning of the arm housing in the electric arc furnace.

Abstract: An apparatus for transferring the electrical energy from a furnace transformer to the electrodes of a three-phase arc furnace held by coplanar mast arms. A mast arm for the center current phase is made of aluminum or a material with a similar permeability. The conductor of the center current phase, which is made of at least one high-current tube made of a material with good electrical conductivity, is mounted in insulated fashion in the mast arm and has a smaller geometrical diameter than the conductors for the outer current phases provided by the other two mast arms.

Abstract: An electrode assembly for a glass melting furnace has an electrode body supported by two elongated steel tubes. Current is supplied to the electrode body by a current supply tube disposed between the two support arms. A holding fixture joins the two support arms to the electrode body. The tube extends through the holding fixture to connect with the electrode body, thus to provide a firm electrical connection with the tube and good mechanical connection with the support arms.

Abstract: In direct-current arc furnace the arc is deflected in a direction away from the current supply means (19) through the action of the high-current lines (18) extending under the furnace vessel. This leads to the thermal overloading of a part of the furnace vessel walls. If the high-current lines (18a) are for the major part laid in a plane above the furnace bottom, on or below the furnace platform (20), and are taken downwards to the connection fittings (10) on the furnace bottom only on the side of the furnace vessel (1) opposite the current supply means, the arc will again burn symmetrically.

Abstract: A refractory is laid on a base plate provided with a connector for the connection of a power source apparatus. Many electrode pins are inserted through the refractory and fixed in the base plate at their lower ends. The base plate is made of a steel upper plate member and a copper lower plate member overlapped one on the other and the lower end portions of the many electrode pins are electrically connected to the lower plate member through the upper plate member. When a DC electric arc furnace is operated, the electric current supplied to the connector reaches all the electrode pins mainly through the lower plate member in the base plate and flows from there homogeneously through the pins into the molten metal pool in the furnace.

Abstract: An electrode carrier arm for an electric arc furnace consists of an arm part (10) and of a electrode-clamping device and is produced so as to be current carrying from a material of high conductivity. Between the arm part and the electrode-clamping device there is a flanged connection consisting of flanged plates (11, 12) which limit a cooling-liquid cavity (20, 29) on both sides and which themselves contain passage orifices (21) for the cooling liquid from one cooling-liquid cavity to the other. This allows an effective cooling of the flanged plates and consequently a direct supply of current via the flanged connection when the carrier arm is produced from light metal.

Abstract: A nonconsumable water-cooled electrode for electric metal smelting furnaces which includes inner and outer concentric steel tubes defining an annular space therebetween through which cooling water may be passed. A tungsten tip is attached to the tubes at their lower ends. Electric current is introduced through a plurality of copper bars attached to the tungsten tip at one end and to a copper plate at the upper end. The copper plate is adapted to attach the electrode to a suitable electrode carrier. A central pipe is provided through which an inert gas, such as argon, may be passed through the electrode.

Abstract: The present invention relates to a method and a means for continuous production of elongated carbon bodies having a constant or substantially constant cross-section where a casing filled with unbaked paste consisting of carbon and a carbon containing binder is continuously baked to a solid carbon body by heating by means of direct electric current. The first terminal of the direct current source is being slidably connected to the casing through a plurality of vertical ribs extending radially outwards from the casing, said ribs being made from a current conducting material, and the second terminal of the direct current source being connected to the baked part of the carbon body or to a bottom contact in a smelting furnace in which the carbon body is consumed. The casing containing the carbon containing paste is continuously or substantially continuously moved in axial direction by means of slipping- and holding means.

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: An electrode arrangement for passing into an electroarc or reducing furnace includes a plurality of cooling jacket capsules each surrounding an electrode and having at least two longitudinal openings each of angular width about 40 degrees; wearproofed current feeders are inserted, possibly insulatively embedded in the openings; one of the openings of each capsule facing the opening of another of the capsules.

Abstract: An arc furnace particularly for smelting of steel comprises three electrodes arranged symmetrically on a circle and connected to the phase by contact pads mounted on horizontal carrier arms.For optimizing the current loading of the contact pads and for minimising reactive losses of the arrangement, the contact pads are arranged centrosymmetrically within the electrode pitch circle.

Abstract: A copper contact jaw is insulated from and releasably fastened to an electrode mount (4) of an electric furnace to transfer current from input leads to an electrode (2). A long service life and secure insulation are attained by using hard copper for the contact jaw and by coating the contact jaw, at least at where it faces the electrode mount (4), with a metal adhesion layer and a layer of ceramic insulating material on the adhesion layer.

Abstract: In an arc furnace both of the open-air and submerged arc type an electrode column able to perform angular movements in one or in both directions alternatively about its axis during furnace operations and, at the same time, it can be moved vertically so as to allow the tip level to be changed as usual, as it is necessary in the furnace operation to achieve the best electric arc.

Abstract: A current feed for an electrode of an electric smelting furnace. The current feed conductors lead to the electrode above the furnace hearth, and a current feed element surrounds the electrode and is arranged coaxially to the electrode and concentrically to the current feed conductors. Contact jaws are arranged concentrically to the electrode. The current-conducting cross section of the current feed element varies continuously from a maximum on the side away from the furnace axis to a minimum on the side adjacent to the furnace axis.

Abstract: Electrode holder system for electrothermic smelting furnaces comprising current clamps for conducting electric current to an electrode and hydraulic cylinders for moving the electrode up and down. The cylinders are connected to the electrode via an electrode frame and releasable clamping means. At least two vertical rails are arranged parallel to the electrode. The rails are at their upper ends suspended from a suspension frame and have a stopper means on their lower ends. The stopper means represents the lower limit for the movement of the current clamps. The electrode holder system combines regulation of the tip position with automatic feeding of the electrode.

Abstract: A shroud assembly for an electric arc furnace in which a plurality of electrodes extend through the roof of the furnace and are adjustably positonable in a clamping type holder. The shroud is secured to each of the electrode holders and extends through the roof into the furnace, the shroud having a conductive ring disposed in the lower end of the shroud with the radial spacing between the lower end of the ring and the electrode being sufficiently small to provide substantial flow resistance to corrosive furnace gases tending to pass between the electrode and the ring, and the shroud having sufficient axial length to provide an abutment surface for the electrode, and lateral support, when the electrode is displaced from its normally vertical position thereby reducing the bending moment tending to break the electrode upon such displacement.

Abstract: A method and device for clamping the electrode contact shoes (2) around the electrode (1) of an electric furnace, comprising one pressure element (3) which is advantageously hydraulically operated and uniform and which surrounds the electrode contact shoes and clamps them against the electrode (1) under the action of pressure on the pressure element.

Abstract: An apparatus for adjustably supporting a vertical electrode for an arc-type furnace. The apparatus includes an upper stationary electrode clamping structure and a lower adjustable electrode clamping structure suspended from the upper structure by adjustment screws. The two clamping structures are mounted on a carriage movable linearly into and out of registry with the furnace to accommodate maintenance and repair. Each clamping structure comprises an arcuate electrical contact and wedge-type slips engaging the periphery of the electrode in opposition to the electrical contact, the slips being spring-biased into electrode engagement and cam actuated from electrode engagement. The cams are actuated by a common shaft extending between the two clamping structures, so that the electrode is released from one clamping structure when engaged by the other clamping structure.

Abstract: The contact urging pressure force is provided through corrosion proof bellows interposed between two covers, one being affixed to a cooled electrode carrier ring, the other one being provided for obtaining the contact urging force; the interior of the bellows contains springs opposing the hydraulic force, and further containing a check valve whose holding element is affixed to the second mentioned cover, closing the opening of the first mentioned cover as long as the hydraulic pressure does not exceed a certain amount.

Abstract: Electrode holder system for electrothermic smelting furnaces comprising current clamps for conducting electric current to an electrode and hydraulic cylinders for moving the electrode up and down. The cylinders are connected to the electrode via an electrode frame and releasable clamping means. At least two vertical rails are arranged parallel to the electrode. The rails are at their upper ends suspended from a suspension frame and have a stopper means on their lower ends. The stopper means represents the lower limit for the movement of the current clamps. The electrode holder system combines regulation of the tip position with automatic feeding of the electrode.

Abstract: To provide an axially variable means of fixation, an electrode for electric arc furnaces is held via a spacing means comprising radially movable contact elements and metallic spacers. The contact elements may be pressed radially inwards against the electrode by means of clamping jaws, thus constituting a solid mechanical and electrical contact between the electrode clamp and the electrode proper.

Abstract: A sliding contact arrangement for transmitting heavy currents to and from a bus bar has a cage with conductive contact faces and an arrangement to cause a conductive sliding contact to bear on the bus bar and only one of the contact faces.

Abstract: An electrode for electric arc furnaces, comprising an upper, metallic, water-cooled section and a lower section of consumable material, such as graphite, is held in its given position by means of an electrode support arm 1,2. The connection elements for electric power and liquid coolant 12, 6, 25 are integrated in the electrode support arm and are designed as plug connections.

Abstract: A water-cooled arc furnace electrode includes a hollow metallic jacket having a cylindrical wall portion supported in spaced relation from a graphite electrode. A shell is spaced from and surrounds the wall portion and has a section extending below the wall portion and upwardly into engagement with the lower end thereof. A baffle is disposed between the wall portion and the shell to define a first cooling fluide passage for water flowed downwardly between the shell and the baffle and a second passage extending upwardly between the baffle and the wall portion. A plurality of spaced electrical contact members are mounted on the lower portion of the shell and are in pressure engagement with the electrode. The shell and the contacts provide a current path around a proportion of the electrode for increased conductivity and to minimize electrode oxidation.

Abstract: A method and device for facilitating the maintenance and replacing of the contact shoes of the electrodes in an electric-arc furnace, the supporting mantle of the contact shoes consisting of two sections, the lower one of which can be lifted, together with the contact shoes, telescopically over the upper section, whereby the contact shoes rise above the furnace hood.

Abstract: The present invention relates to a holder assembly for electrodes in an electrothermal smelting furnace. The holder assembly comprises a plurality of contact clamps which are pressed towards the electrode by means of pressure producing means and an externally arranged thrust member. The holder assembly is further equipped with means for communicating current, coolant and pressure agent to the contact clamps. The holder assembly is constructed as a single integrated unit where current, coolant and pressure agent are conducted through the same supply pipes. The supply pipes serve additionally as support for the holder and consequently the electrode. The pressure producing means is constructed as an integral part of the contact clamps while the supply pipes are welded on to the contact clamps.

Abstract: The present invention relates to an electrode holder assembly for self-baking electrodes in an electrothermic smelting furnace. The electrode comprises an electrode casing having vertical fins projecting radially outwards from the casing. A plurality of clamping means are slidably arranged on said fins. The clamping means function both as means for conducting current into the electrode and as means for holding the electrode in position. The clamping means impose only tangentially forces on to the electrode in the baking zone. Protection shields are preferably arranged in lateral direction around the electrode, the shields being arranged between the clamping means or outside. Means for supplying air/gas into the space between the shields and the electrode in order to improve the baking conditions are provided.

Abstract: An electrode support mechanism and method for use in electric arc melting or smelting furnaces wherein a pair of horizontal, superimposed arms are each provided with clamping devices at their outer end for supporting and supplying electric power to a vertically disposed electrode depending into an arc furnace. The arms are each supported on a vertical support post; the upper arm is fixed to the post and the lower arm which normally carries the electrode is movable relative to the post to adjust the electrode to maintain a constant arc at the furnace. The movable arm is moved vertically by a jack screw carried by the upper arm and depending into contact with the lower arm. The clamping devices at the ends of the arms are spring-biased toward contact with the electrode, and a linking mechanism is provided to alternately release the arm clamping mechanisms from the electrode under the control of an actuating system utilizing fluid pressure actuated cylinders.

Abstract: A holder assembly (2) for an electrode (1) in an electrothermal smelting furnace is movable suspended from a suspension means and comprises a plurality of contact clamps (3) which are pressed towards the electrode (1) by means of pressure producing means and an externally arranged thrust member (5). The holder assembly (2) is further equipped with means for supplying current to the electrode. The thrust member (5) is formed of the cooling shield which surrounds the electrode and the holder assembly. On the inner surface of the cooling shield (5) a plurality of vertical, current conducting rails (7) are arranged. Sliding contacts (10) arranged on the pressure producing means (4) are thrusted against the rails, providing proper electrical contact. The rails (7) are preferably insulated from the shield (5). The shield (5) may preferably be stationary arranged with respect to the electrode and constitute an integral part of the furnace roof/hood (6).

Abstract: An electrode contact assembly includes spaced-apart U-shaped hollow tubular members each having a contact shoe affixed to each leg. A pressure ring surrounds the contact shoes for forcing the same into pressure engagement with the surface of an electrode. The tubular members are adapted for connection to sources of electrical energy and cooling fluid. A support ring concentric with the electrode and spaced above the pressure ring independently supports the pressure ring and the tubular members.

Abstract: A furnace electrode clamp comprises a metallic body portion (3), an electrically insulated U-shaped band (7) mounted for movement about the body and adapted to embrace the electrode (8) and at least one (preferably two) electrode contact piece(s) (13) mounted on the body and against which the electrode is clamped by the band. The or each contact piece is made from highly conductive material and is water-cooled. The small surface over which contact is made enables a high force/unit area to be established at the contact/electrode interface than hitherto and the direct water cooling facility enables higher current densities to be withstood.