Abstract: During the production of non-stainless steel, slag containing a high proportion of metal oxides, primarily iron oxide, is formed during the smelting of the solid material in the electric arc furnace. The concentration of the iron oxide often reaches values of more than 20%. This slag has a poor foaming capability and does not permit the typical characteristics of a carbon steel slag to be achieved. In order to cause such a slag to foam, according to the invention it is proposed to load the electric arc furnace with pellets or briquettes (8) which consist of a defined mixture of an iron oxide carrier and an iron carrier as ballast material, of carbon as reducing agent and also of a binder material, which react in the electric arc furnace in a reducing manner, floating under the slag (7) in the steel melt (6). The reaction gases (12) produced in this way consist primarily of carbon monoxide and advantageously support the foaming of the slag.

Abstract: A method and a device for remelting metal in an electric furnace includes forming a slag bath to form molten material electrodes. The molten metal of the material electrodes solidifies in block form in a crucible apparatus as a result of cooling in such a way that a block growth forms from a block base using a progressing solidification process, wherein the block base is heated by applying energy directly to the block base to influence the cooling process.

Abstract: During the production of stainless steel, a slag is formed during the melting of the solid material in the electric arc furnace, the slag having a high degree of metal oxides, particularly chromium oxide. The chromium concentration often reaches values of more than 30%. Currently, such slags cannot be reduced to a desired degree due to their composition. In order to minimize the resulting high loss of recyclable material, the invention provides to charge the electric arc furnace with pellets, or briquettes (8), which are made of a defined mixture of an iron carrier as the ballast material, carbon, or carbon and silicon, as the reducing agent, and a binder, wherein they react beneath the slag layer (7) in the steel melt (6) with the metal oxides of the slag (7), particularly with the chromium oxide present, in a floating, chemical, and reducing manner. The reaction gases (12) produced in the process, which are mainly made of carbon monoxide, advantageously support a foaming of the slag (7).

Abstract: A method (20) of fabricating a large component such as a gas turbine or compressor disk (32) from segregation-prone materials such as Alloy 706 or Alloy 718 when the size of the ingot required is larger than the size that can be predictably formed without segregations using known triple melt processes. A sound inner core ingot (12) is formed (22) to a first diameter (D1), such as by using a triple melt process including vacuum induction melting (VIM), electroslag remelting (ESR), and vacuum arc remelting (VAR). Material is than added (26) to the outer surface (16) of the core ingot to increase its size to a dimension (D2) required for the forging operation (28). A powder metallurgy or spray deposition process may be used to apply the added material. The added material may have properties that are different than those of the core ingot and may be of graded composition across its depth. This process overcomes ingot size limitations for segregation-prone materials.

Abstract: An electroslag refining apparatus includes upper and lower integral crucibles, with the lower crucible having a drain. In situ hot start is effected by depositing in the lower crucible a pre-refined starter. The starter is melted in the lower crucible to form a starter pool, and slag is deposited atop the starter pool for being melted thereby to develop a slag pool thereatop. An ingot electrode is lowered through the upper crucible to immerse a tip thereof into the slag pool. The electrode is powered to effect resistance heating of the slag pool to melt the electrode tip. The slag and starter pools are increased in volume into the upper crucible, with the drain then being opened to effect steady state operation.

Abstract: An electroslag refining apparatus includes upper and lower integral crucibles, with the lower crucible having a drain. In situ hot start is effected by depositing in the lower crucible a pre-refined starter. The starter is melted in the lower crucible to form a starter pool, and slag is deposited atop the starter pool for being melted thereby to develop a slag pool thereatop. An ingot electrode is lowered through the upper crucible to immerse a tip thereof into the slag pool. The electrode is powered to effect resistance heating of the slag pool to melt the electrode tip. The slag and starter pools are increased in volume into the upper crucible, with the drain then being opened to effect steady state operation.

Abstract: A method for refining and casting metals and metal alloys includes melting and refining a metallic material and then casting the refined molten material by a nucleated casting technique. The refined molten material is provided to the atomizing nozzle of the nucleated casting apparatus through a transfer apparatus adapted to maintain the purity of the molten refined material. An apparatus including a melting and refining apparatus, a transfer apparatus, and a nucleated casting apparatus, in serial fluid communication, also is disclosed.

Abstract: A consumable electrode feed system for a refining system provides consumable electrodes to a refining system. The consumable electrode feed system comprises a side feed device that feeds consumable electrodes to a refining system in a first direction; a refining feed device that feeds consumable electrodes to a refining system in a second direction, in which the second direction being generally orthogonal to the first direction; and a connection system for connecting fed consumable electrodes to each other. The consumable electrode feed system allows for a predetermined amount of a consumable electrode to be refined in the refining system, and can position another consumable electrode above a previously fed consumable electrode. The connecting system then can connect a fed consumable electrode to a previously fed consumable electrode thus avoiding refining operation.

Abstract: A method for controlling electromagnetic flux concentration in a discharge guide tube for a metal refining apparatus is provided. The discharge guide tube comprises a base plate, an extension, a central orifice that extends through the extension from a source of liquid metal to an outlet in the discharge guide tube for directing a stream of metal therethrough, and an interior discharge guide tube flux concentration configuration; an induction heater system that generates an electromagnetic field in the discharge guide tube, the induction heater system being disposed on the extension with a gap defined therebetween, the induction heater system and the discharge guide tube being capable of relative vertical movement and subsequent positions with respect to each other with the gap being essentially constant.

Abstract: A bottom pour electroslag refining system refines raw material into refined liquid metal. The bottom pour electroslag refining system comprises an electroslag refining crucible; a slag; a bottom pour structure that comprises an orifice from which refined liquid metal from the electroslag refining crucible can flow as a stream of refined liquid metal; and a current path. The current path is defined in the bottom pour electroslag refining system for applying current to the raw material for melting and refining the raw material. The melted and refined raw material forms a refined liquid metal pool in the electroslag refining crucible. The current that is applied by the current path is sufficient to provide the refined liquid metal in the refined liquid metal pool with a viscosity under which the refined liquid metal can flow through the orifice under its own viscosity.

Abstract: The flowrate of a stream discharged from a drain in a vessel is measured by imaging the stream, measuring a diameter of the stream image, and calculating the flowrate based on the measured diameter. A video camera may be aimed below the drain for imaging the stream. A computer is joined to the camera for measuring the diameter of the stream and calculating a corresponding flowrate therefor.

Abstract: An article that comprises a fine-grain, homogeneous microstructure is essentially oxide- and sulfide-free and segregation defect free. The article is produced by a process that comprises forming a source of clean refined metal that has oxides and sulfides refined out by electroslag refining; and forming the article by nucleated casting. The invention also sets forth the article made by a system for implementing the clean metal nucleated casting process.

Abstract: A guide tube structure for flux concentration is provided. The discharge guide tube comprises a central orifice that extends from a source of metal to an outlet in the discharge guide tube for directing a stream of melt therethrough; a structure that generates an electromagnetic field in the discharge guide tube; and an interior discharge guide tube flux concentration configuration that is capable of concentrating at least one of heat, electromagnetic field, and electromagnetic flux onto the stream of melt that flows through the central orifice. The electromagnetic field is applied at a substantially constant level.

Abstract: Systems for controlling the superheat of the stream of molten metal from an electroslag refining apparatus is taught. The systems include the introduction of unrefined metal into an electroslag refining process apparatus in which the unrefined metal is first melted at the upper surface of the refining slag. The molten metal is refined as it passes through the molten slag. The refined metal is collected in a cold hearth apparatus having a skull of refined metal formed on the surface of the cold hearth for protecting the cold hearth from the leaching action of the refined molten metal. A cold finger bottom pour spout or exit orifice is formed at the bottom of the cold hearth to permit dispensing of molten refined metal from the cold hearth.