Abstract: A method of making an electrode assembly for a furnace includes providing a heating element within the furnace. The method further includes providing a power feedthrough having an end portion that extends into the furnace to couple with the heating element. The power feedthrough includes a conductive member for transmitting electricity to the heating element. The method includes cleaning an exterior surface of the conductive member proximate the end portion of the power feedthrough. The method further includes a step of applying an electroless nickel plating to the exterior surface of the conductive member for preventing corrosion of the conductive member within the furnace. The method also includes connecting the end portion of the power feedthrough to the heating element.

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: In various embodiments, an electrode has a shaft extending from an electrode head and a cooling passage extending from an open end disposed at an attachment end of the shaft to a closed end disposed within the electrode head.

Abstract: An in-liquid plasma electrode according to the present invention is an in-liquid plasma electrode for generating plasma in a liquid and has an electrically conductive member having an electric discharge end surface in contact with the liquid, and an electrically insulating member covering an outer periphery of the conductive member at least except the electric discharge end surface. Preferably, d and x satisfy ?2d?x?2d, where d is a length of a minor axis of the cross section when a conductive end portion of the electrically conductive member having the electric discharge end surface has an approximately circular cross section, or d is a length of a short side of the cross section when the conductive end portion has an approximately rectangular cross section, and x is a distance from a reference plane to a plane containing the electric discharge end surface when the reference plane is an end surface of the electrically insulating member that is approximately parallel with the electric discharge end surface.

Abstract: A fused magnesia ingot being discharged from an electric furnace at extremely elevated temperatures is thermally insulated to improve product yield. Thermal insulation provided with a blanket covering of refractory material can be used for this purpose.

Abstract: An object of the invention is to provide an ingot having improvement of and a prevention of occurrence of segregation when electroslag remelting method is used for producing a large size ingot and a super alloy which is sensitive to segregation. According to the present invention, the electrode for electroslag remelting method has a hole formed along an axial direction in the core of an electrode. Therefore, the molten pool is made shallow so that flat and segregation is prevented from occurring. Consequently, an ESR ingot of good quality is accomplished with an excellent surface and is free from segregation. Moreover, an electrode melting rate is increasing and efficiency is improved.

Abstract: A process for producing a turbine rotor using an ingot in which segregation is prevented effectively when ESR is used to produce a large-sized ingot. A hole is formed along an axial direction in the core of an electrode. The molten pool is made shallow and flat and segregation is prevented from occurring. Consequently, an ESR ingot of good quality offering an excellent surface is obtainable as it is free from segregation. Moreover, an electrode melting rate is increased and efficiency is improved so that a high quality turbine can be manufactured from the ingot.

Abstract: A sealed connection for a sleeve and jacket for protecting a molybdenum electrode mounted through the wall of an electric glass furnace. Around the electrode in the wall is a stainless steel sleeve coated on the inside with a fused alumina and having an outwardly extending flange at its outer end which engages the outer wall or shoulder in the aperture in the wall through which the electrode extends. The flange has an axially outwardly extending rib of V-shaped radial cross-section which seats and centers in an annular V-shaped groove around the inner end of a water jacket that surrounds the electrode outside the furnace. Refractory sealing gaskets are placed between the flange and the wall of the furnace and in the cooperating grooves and ribs of the sleeve and water jacket. The sealed cylindrical annular space around the electrode between it and the sleeve and the jacket is filled with nitrogen to prevent oxidation of the molybdenum electrode.

Abstract: A laminated carbon cathode includes two layers of carbon blocks, i.e. and the upper layer of graphite of graphitised carbon, and a lower layer of a cheaper anthracite carbon. The two layers are so displaced with respect to one another that there are no vertical seams leading straight from the upper surface of the carbon cathode to the its underside. Dividing the cathode into two horizontal layers is combined with the embedding of current-carrying steel conductors in precise grooves between the layers. In order to capitalize on the good electrical conductivity of aluminum, an aluminum extension is friction-welded to each steel conductor as close to a shell enclosing the cathode while at the same time a collar is formed which provides an air-tight seal at the point where the cathode bar enters the side of the shell.