Abstract: The present invention relates to an electric channel inductor assembly. A nonremovable, hollow and nonmagnetic channel mold is used to form the one or more flow channels of the electric channel inductor assembly for electromagnetic circulation of a molten metal composition. A heated fluid medium is circulated in the hollow interior of the channel mold after the mold is situated in the inductor assembly to heat treat the refractory surrounding the exterior walls of the mold. After heat treatment a liquid is supplied to the hollow interior of the mold to chemically dissolve the channel mold prior to circulation of the molten metal composition.

Abstract: The present invention relates to an electric channel inductor assembly and method of forming an electric channel inductor assembly. A nonremovable, hollow, nonmagnetic channel mold is used to form the one or more flow channels of the assembly. A heated fluid medium is circulated in the hollow interior of the mold after the mold is situated in the assembly to heat treat the refractory surrounding the exterior walls of the mold. After heat treatment a liquid is supplied to the hollow interior of the mold to chemically dissolve the mold.

Abstract: The invention comprises a double loop channel type induction furnace of which the floor has a base on a first side of its hearth and a ramp which rises from the base to terminate in a plateau above the passages at a location distal from the first side. The ramp and plateau extends at least partly between opposing end walls of the furnace, and the plateau includes a trench which extends at least partly between opposing ends of the plateau. The trench is in fluid communication with the passages and the bottom of the trench is located in a plane higher than the plane in which the furnace floor is located. The base of the furnace floor is in fluid communication with the central passage by means of a floor passage that extends from the base of the floor to the central passage through the ramp below the trench.

Abstract: An AC melt to bushing current detector (FIG. 4) for a channel induction furnace (FIG. 1) which can detect when molten metal from the loop (122) in a saturated inductor (FIG. 5) has come in contact with the metal bushing (236) whereupon the power to the induction coil (234) is turned off, preventing a catastrophic molten metal run out through the bushing (236).

Abstract: An induction-heated furnace having a shell with at least a portion lined with refractory material having walls and a floor. At least one induction heater is mounted to the floor of the furnace refractory material that communicates with the interior of the furnace through a throat. The throat length is substantially longer than the throat length of the induction heater to aid the distribution of molten metal in the furnace.

Abstract: Gastight and vacuum-tight chamber intended to be used in a device for heating a product advancing inside the chamber by electromagnetic induction, characterized in that it comprises a gastight and vacuum-tight sheath made of an electrically insulating, gastight and vacuum-tight material, the inner faces of the sheath being protected by a heat shield consisting of a matrix of tiles made of a thermally insulating material and of a plurality of tubes cooled by the flow of a fluid, the latter being trapped in the matrix of tiles.

Abstract: A channel inductor and a furnace for melting, holding or refining metal. The channel inductor has a closed-loop core, a primary winding arranged around the core and a refractory lining in which the winding and core is partly enclosed and in which an inductor channel is formed. The channel inductor also has a detector to detect metal penetration of the refractory lining.

Abstract: A heat shielding cladding for walls, ceilings, or similar surfaces, especially of industrial furnaces, including butted together parallelepipedal modules that are secured to the wall and comprise a plurality of held together and compacted fiber mat webs that are prestressed in a direction parallel to the wall. Adjacent modules are held together in a permanently flexible bond on non-prestressed sides thereof by at least one filamentary, temperature-resistant binder that is guided, without kinking, from a surface of the heat shielding cladding that is remote from the wall to the wall.

Abstract: A shallow vessel (50,52) for being horizontally disposed when containing a molten metal or metal alloy (66) for meniscus coating one side of a clean metal strip (34A) when the strip is moved vertically past one side of the vessel. The vessel includes a shell (68) such as austenitic stainless steel, a refractory lining (70), a molten metal departure lip (72) mounted on the upper surface of the side of the vessel, a spirally shaped induction coil (64) for maintaining the molten metal above its melting point and a flux concentrator (74). The induction coil is positioned below the refractory lining and the flux concentrator is positioned below the induction coil. The induction coil and the flux concentrator underlie the area occupied by the molten metal.

Abstract: An induction furnace for reflowing a portion of an optical preform in order to draw a lightguide fiber therefrom. The furnace has an axially located tubular iridium susceptor which is centrally disposed within a beaker and a sleeve is positioned concentrically around the susceptor. The sleeve is surrounded by an insulating grain. A high frequency coil is energized to couple its electromagnetic field to the iridium susceptor to heat and reflow a portion of the preform in order to draw the fiber therefrom. The furnace housing is sealed to provide an inert, non-oxidizing atmosphere for the iridium susceptor.

Abstract: A cooling tube (T) is incorporated into each conductor (C1) of the coil. The current carried by this conductor is divided between the strands which are maintained in thermal contact with the tube even in transposition or twist areas in which the conductor undergoes particularly marked deformations. The conductor features at least one half-turn twist between the electrical terminals of the coil.

Abstract: A high frequency core and coil electric metal melting furnace is shown. This furnace has a lined channel in its inductor for carrying the molten metal. The invention provides an improved inductor for a core and coil furnace that is not subject to leakage of the molten metal from the channel into the rammed refractory support bed for the channel which leakage otherwise shortens the lift of the furnace. Also a method of lining the channel in the inductor for carrying the molten metal which forms the core is disclosed.

Abstract: A lining for use in an aluminum reverberatory furnace or the like for heating molten aluminum in a cavity which cavity is formed by a roof, sidewalls and a bottom which are to be lined with refractory materials. The lining comprises a band of hot face refractory material around the interior periphery of the cavity sidewalls for contacting molten aluminum in the furnace at the normal operating levels of the upper surface of the molten aluminum. A layer of backup refractory material is interposed between the furnace shell and the band of hot face refractory material.

Abstract: A refractory product is shown in the form of a dense sintered alumina-chromia, zirconia-alumina-silica, zirconia-alumina body, or zirconia-chromia-alumina having less than about 8% of homogeneously distributed closed porosity formed by sintering an intimate interdispersion of fine particles of alumina-chromia, zirconia-alumina-silica, zirconia-alumina, or zirconia-chromia-alumina.

Abstract: A method of and an apparatus for forming a liner in an induction furnace is disclosed. The apparatus includes a hopper for storing particulate refractory material and a plurality of material delivery tubes communicating with the hopper and extending into the space between a form disposed in the furnace and a furnace wall. A compaction plate is also disposed in the space and includes a plurality of bores therethrough which communicate with the material delivery tubes. Vibrating means vibrate the hopper, material delivery tubes and the compaction plate so that the particulate refractory material is transferred from the hopper to the space between the form and the furnace wall through the material delivery tubes and the compaction plate bores and is compacted by the compaction plate to form the liner.

Abstract: Disclosed is a method for measuring the extent of slag deposit buildup in the channel of a channel induction furnace during operation. The method comprises measuring an initial temperature rise factor in the furnace at a time when no slag deposits are present, measuring a subsequent temperature rise factor in the furnace after the furnace has been in operation for a period of time, correcting the subsequent temperature rise factor for any changes in the operating temperature and power levels applied to the furnace which may have taken place between the time of the measurement of the initial temperature rise factor and the time of the measurement of the subsequent temperature rise factor, and determining a quantity which is indicative of the extent of slag deposit buildup in the channel from the difference between the initial and subsequent temperature rise factors.