Abstract: The present invention relates to a process and apparatus for controlling an electromagnetic casting system. The process and apparatus utilize at least one sense loop and an electrical parameter relating to the sense loop, e.g. the mutual inductance between the sense loop and a containment inductor, to control during casting the height of the contained head of molten material and/or the ingot size. In a first embodiment, a sense loop is positioned in the air gap between the containment inductor and the outer surface of the forming ingot or the molten metal head, preferably in a location in the vicinity of the liquid-solid interface. In a second embodiment, a plurality of sense loops are used to control the casting system.

Abstract: Thin metal sheets are cast by magnetically suspending molten metal deposited within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled to form a solid metal sheet. Magnetic flux increases as the molten metal sheet moves downward and decreases as the molten metal sheet moves upward to stabilize the sheet and maintain it in equilibrium as it is linearly displaced and solidified by cooling gases. A conducting shield is electrically coupled to the molten metal sheet by means of either metal sheet engaging rollers or brushes on the solidified metal, and by means of an electrode in the vessel containing the molten metal thereby providing a return path for the eddy currents induced in the metal sheet by the AC coil generated magnetic flux.

Abstract: A process for electromagnetically casting molten material into a thin strip having a substantially constant thickness. An inductor is provided for electromagnetically shaping the molten material. The material is electromagnetically shaped into a strip having a desired thickness. Variations in the thickness of the molten material are automatically reduced during the shaping step by selecting the frequency of the current applied to the inductor so that the thickness of the strip is about 1.8 to about 2.6 current penetration depth.

Abstract: Apparatus for producing dense homogeneous metal cast in long lengths by introducing liquid metal into the lower portion of a casting vessel in the presence of an elongated upwardly-traveling alternating electromagnetic levitation field that provides a levitation ratio of from 75% to 200% of the weight per unit length of the liquid metal. The apparatus provides cooling for solidifying the metal while moving upwardly through the field, and a withdrawal mechanism for removing solidified metal product from the upper portion of the field. The electromagnetic field producing means is designed to establish an alternating electromagnetic field having a frequency at or near a value F=36.rho./D.sup.2 where F is the frequency in kilohertz, .rho. is the resistivity of the liquid metal column in micro-ohm-centimeters and D is the average diameter of the solidified metal rod product in millimeters.

Abstract: An apparatus is provided for electromagnetically coiling a molten material into a longitudinally extending casting defining a longitudinal axis thereof. The casting has a desired cross section extending perpendicular to the longitudinal axis. At least one portion of the outer peripheral surface of the casting extends transversely of the longitudinal axis and has a small radius of curvature. The apparatus includes an inductor extending transversely about the molten material for providing an electromagnetic containment force field acting on the outer peripheral surface of the molten material to form the desired cross section. The improvement comprises a device for turning the electromagnetic containment force field about the longitudinal axis to cause a corresponding turn of the transverse cross section of the molten material about the longitudinal axis.

Abstract: The cooling of a continuously cast ingot as it emerges from the mold, during casting, is carried out by applying coolant directly to the ingot around its circumference. In order to reduce the extent of doming, which occurs to the ingot base when cooling is too strong, the coolant is applied, at least at the start of the drop, to zones via streams of coolant. The process can be realized in practice particularly simply with an electromagnetic continuous casting mold which has a cooling device featuring a nozzle, with a ring shaped opening for liquid coolant, directed at the surface of the ingot. A deflecting sheet with turret shaped tongues separated by openings is provided projecting into the path of the coolant emerging from the ring shaped gap. The deflecting sheet is positioned parallel to the main ingot axis and can be moved parallel to that axis.

Abstract: A method and apparatus is disclosed for casting conductive and semiconduce materials. The apparatus includes a plurality of conductive members arranged to define a container-like area having a desired cross-sectional shape. A portion or all of the conductive or semiconductive material which is to be cast is introduced into the container-like area. A means is provided for inducing the flow of an electrical current in each of the conductive members, which currents act collectively to induce a current flow in the material. The induced current flow through the conductive members is in a direction substantially opposite to the induced current flow in the material so that the material is repelled from the conductive members during the casting process.

Abstract: An apparatus and process for casting metals wherein the molten metal is contained and formed into a desired shape by the application of an electromagnetic field produced by a multi-turn inductor. The pitch or spacing of individual turns of the inductor is controlled to provide accurately varied electromagnetic pressure. The process includes the step of varying the distance between turns and/or the height of the individual turns to control the electromagnetic forces and balance the metallostatic pressure within the molten metal being cast.

Abstract: In a continuous casting process the flow of molten metal is continuously fed into a mould to be further submitted to the action of the magnetic field generated by an electrical inductor and a stabilizing coil so that a column of molten metal is formed. The column of molten metal is then cooled to produce a continuous strand or ingot. The current supplied to the stabilizing coil has its phase lagging behind that of the current in the inductor with the phase angle between them ranging from 95.degree. to 165.degree.; the amplitude of current in the stabilizing coil being 0.1 to 0.4 times the current amplitude in the inductor. Apparatus for performing the above-described continuous casting process comprises a mould formed by an electromagnetic inductor and a stabilizing coil from a nonmagnetic material in the form of a triangle arranged coaxially with the inductor and having its apex oriented inside the mould.

Abstract: The present invention relates to a process for the electromagnetic casting of metals. The process is characterized by simultaneously using a stationary field and a variable field at a suitable frequency for producing both radial vibrations within the metal which is not yet in a solidified condition and limiting agitation of the metal. The invention can be used in any circumstance where both the structure and the surface condition of the cast products are to be improved.

Abstract: A method and apparatus is disclosed for electromagnetic casting of metal and alloy ingots of rectangular or other desired shape having corners or portions of small radius of curvature. A coolant application system is provided which lessens the severity of the rounding off or radius of the corners of the electromagnetically cast ingots by contouring the coolant application rate and/or elevation so that the rate and/or elevation is a minimum at the corners of the ingot.

Abstract: The present invention concerns a process for vertical continuous casting at speeds which are close to a meter per minute. The process is characterized in that the use of a top feeder head and an electromagnetic field are combined and that, by controlling the position in respect of height of the top feeder head and the cooling system relative to the field generating means, the distances between certain parameters such as the solidification front and the base plane of the top feeder head are maintained constant in the course of the casting operation. This process makes it possible to cast aluminium and alloys thereof in the form of billets or plates, the smallest dimension of which does not exceed 150 mm and which have a surface that does not require any scalping treatment.

Abstract: A flux concentrator is disclosed for generating a strong magnetic field. An inductor is provided for generating a primary magnetic field which is weaker than the strong magnetic field. A concentrator body has a hollow interior for receiving material to be acted upon by the strong magnetic field. The body is located within the primary magnetic field and shields the primary magnetic field from the hollow interior. A flux concentrator device is positioned within the hollow interior and has a slot extending therethrough. The flux concentrator device is coupled to the primary field for generating the strong magnetic field within the slot. Structure is provided to vary the size of the slot while the strong magnetic field is being generated in the slot.

Abstract: A process and apparatus for determining the value of parameters which affect emissivity of radiation from a metal load in an electromagnetic casting system. Infrared radiation being emitted from the surface of the load is sensed by an array of fiber optic filaments secured within elements of the electromagnetic casting system. Radiation signals are transmitted by the filaments to a signal processor which enables readout display of electromagnetic casting parameters such as liquid temperature, maximum load temperature, position of the liquid/solid interface, and head position.

Abstract: An apparatus and process for casting metals wherein the molten metal is contained and formed into a desired shape by the application of an electromagnetic field produced by a multi-turn inductor. The pitch or spacing of individual turns of the inductor is controlled to provide accurately varied electromagnetic pressure. The process includes the step of varying the distance between turns and/or the height of the individual turns to control the electromagnetic forces and balance the metallostatic pressure within the molten metal being cast.

Abstract: An apparatus and process electromagnetically forms feed ribbon or rod material into a desired thin strip shape. Inductors contain and form the material in molten form into the desired shape. There are at least an upstream and downstream inductor for applying the magnetic field to the molten material. Both the upstream and downstream inductors may be jointly used to contain and form the molten material into the thin strip shape. An alternating current is applied to the inductors to generate the magnetic field. This magnetic field defines a containment zone for the molten material and a gap between the molten material and the inductors. The current is applied to the inductors so that the gap remains substantially constant. The feed material has an upstream and a downstream liquid-solid interface adjacent the upstream and downstream inductors, respectively, which define the molten material head and solid material portions of the material.

Abstract: An apparatus and process for casting metals wherein the molten metal is contained and formed into a desired shape by the application of an electromagnetic field produced by a multi-turn inductor. The pitch or spacing of individual turns of the inductor is controlled to provide accurately varied electromagnetic pressure. The process includes the step of varying the distance between turns and/or the height of the individual turns to control the electromagnetic forces and balance the metallostatic pressure within the molten metal being cast.

Abstract: An adjustable mold for use in electromagnetic casting systems wherein the side walls of the mold are adjustable so as to allow for the casting of ingots of various sizes by a single mold.

Abstract: A multi-strand apparatus and process is provided for casting molten materials into ingots of desired shape. The apparatus comprises a plurality of devices for receiving and electromagnetically forming the molten material into desired shape. Each of the receiving and forming devices includes an inductor for applying a magnetic force field to the molten material. The inductor in operation is spaced from the molten material by a gap extending from the surface of the molten material to the opposing surface of the inductor. An alternating current applying device sends current to its associated inductor to generate the magnetic force field. Circuitry associated with each of the inductors senses variations in their respective gaps. The improvement comprises a pulse width modulating circuit associated with said gap variation sensing circuitry being connected to the alternating current applying device for controlling the application of alternating current to the inductor.

Abstract: An apparatus and process for casting metals wherein the molten metal is contained and formed into a desired shape by the application of an electromagnetic field established by an inductor. The height of the liquid metal head, the location of the liquid-solid interface at the periphery of the forming ingot, and/or variations in the values of these parameters is displayed during the casting run by a system which monitors the in-phase component of the voltage across the inductor to determine variations in the total equivalent series resistance of the electromagnetic casting system as seen by the inductor.

Abstract: A process for casting a material comprising a coolant application device comprising a fluidized bed cooling system. A control system for the fluidized bed cooling system determines the most upstream position at which the fluidized bed contacts the material being cast. The control system is adapted to adjust the pressure differential between the gas used to fluidized the bed of particles and an opposing gas flow. The casting system may be a continuous or semi-continuous one and preferably employs an electromagnetic mold.

Abstract: An apparatus and process for electromagnetically forming a material into a desired thin strip shape. The apparatus comprises a first portion for electromagnetically containing and forming the material in molten form into a cross-sectional shape substantially the same as the desired thin strip shape. A second portion receives the molten material in the thin strip shape from the first portion. In addition, the second portion reduces the distortion in the cross-sectional shape due to surface tension. The second portion includes a device for providing an electromagnetic field having a reduced strength as compared to the strength of an electromagnetic field in the first portion. The electromagnetic field may be reduced in strength by providing an inductor having hollow inner surfaces facing the molten material so as to form substantially straight vertical surfaces in the molten material.

Abstract: An apparatus and process are provided for forming molten thin strip material into a desired thin strip shape. The apparatus comprises a device for electromagnetic forming of the molten material. This device includes a first and second inductor disposed on either side of the molten thin strip material for generating first and second magnetic fields about the first and second edges of the thin strip material. Third and fourth inductors are disposed adjacent opposite edges of the thin strip material for generating third and fourth magnetic fields which interact with the first and second magnetic fields, respectively. Structure regulates the strength of the fields induced by the inductor device to form the molten material into the desired thin strip shape.

Abstract: An electromagnetic casting process and apparatus utilizing an active transformer-driven copper shield. The shield is actively driven with a voltage out of phase with the voltage in the containment inductor with the result that a bucking current is produced in the shield which is out of phase with the current induced in the shield by the inductor. An active transformer-driven duplex variable impedance shield is also disclosed.

Abstract: A method and apparatus for electromagnetic casting of metal and alloy ingots of desired shape having portions of small radius of curvature. A modified shield is provided which provides for a reduction of the electromagnetic field intensity at the corners of the forming ingot by increasing local screening of the field at the corners. Increased local screening at the corners is achieved by locally increasing shield depth, by providing for deeper displacement of the shield, by changing the shield section, or by changing the shield orientation. Also disclosed is a modified inductor which is shaped so as to be located at a greater distance from the portions of small radius of curvature of the ingots than from portions of the ingots adjacent to the portions of small radius of curvature. The modified shield may be combined with the modified inductor and/or with a coolant manifold to simultaneously modify and control coolant application elevation such that the elevation is a minimum at the corners of the ingot.

Abstract: A multi-strand process is provided for casting molten materials into ingots of desired shape. The process uses two inductors for receiving the molten material and applying the first and second electromagnetic force fields to form the molten material into the ingots. The inductors are located adjacent each other so that the first and second force fields interact with each other. A first device is associated with one of the inductors for applying a first alternating current at a first desired frequency to an associated inductor to generate the first magnetic force field. A second device is associated with the other of the inductors for applying a second alternating current at a second desired frequency to generate the second magnetic force field. The second frequency is set to a desired value in relation to the first frequency in order to control the first and second resulting containment currents circulating in the molten material.

Abstract: A multi-strand apparatus and process for casting molten material into at least two ingots of desired shape. Structure is provided for receiving and electromagnetically forming the molten material into ingots of desired shape. Each of the receiving and forming structures includes an inductor for applying an electromagnetic force field to the molten material. When the inductor is in operation, it is spaced from the molten material by a gap extending from the surface of the molten material to the opposing surface of the inductor. The improvement comprises a device for distributing a common alternating current to the inductors to generate the magnetic fields. A device is provided for minimizing variations in the gaps during operation of the casting apparatus.

Abstract: A method of casting metallic strands in a closed pouring or teeming system wherein the metal is cast through a refractory distributor vessel-pouring structure, such as a pouring spout, into an open-ended mold connected in flow communication with the pouring structure. To improve the quality of the strand and to increase the production capacity or output of such installations at the region of a connection plane of the distributor vessel-pouring structure and the open-ended mold the metallic melt is maintained away from the wall of the mold inlet opening by means of a constricting or bundling electromagnetic field.

Abstract: A multi-strand apparatus and process for casting molten material into ingots of desired shape. A plurality of structures are provided for receiving and electromagnetically forming the molten material into the desired shape. Each receiving and forming structure includes an inductor for applying a magnetic force field to the molten material. When the inductor is in operation, it is spaced from the molten material by a gap extending from the surface of the molten material to the opposing surface of the inductor. Structure is provided for distributing a current in the inductor to generate the magnetic field. The improvement comprises a device arranged below the inductor for modifying the current distribution in the inductor to minimize the variations in the gap.

Abstract: A process for electromagnetically containing and forming molten material into a desired thin strip shape. At least two inductors are employed which are powered at respectively different frequencies. The frequency of the current applied to the upstream inductor is substantially lower than the frequency applied to the downstream inductor thereby providing improved efficiency and reduced power consumption.

Abstract: An electromagnetic casting system for casting materials comprising the apparatus and process for electromagnetically containing and forming molten material during a casting run into a desired shape. During the casting run, a liquid-solid interface defines molten material head and solid material portions of the casting. The electromagnetic containing and forming device includes an inductor applying a magnetic field to the molten material. The magnetic field defines a containment zone for the molten material. An alternating current is applied to the inductor to generate the magnetic field. The improvement comprises controlling the location of the liquid-solid interface in the containment zone. The location of the liquid-solid interface along the periphery of the casting is monitored.

Abstract: A method and apparatus for electromagnetic continuous or semicontinuous casting of metals and alloys. A variable coolant application system is used to control the rate of heat extraction from the casting to properly position the solidification front at the surface of the casting without otherwise influencing the containment process through modification of the magnetic field.

Abstract: An apparatus and process is provided for electromagnetically forming a material into a desired thin strip shape. The apparatus and process includes a first portion containing a sump of said material in molten form. A second portion is located downstream of and communicates with the first portion. The second portion defines a containment zone of 5 mm or less for electromagnetically shaping the molten material into the thin strip shape whereby efficiency is improved through reduction of power consumption.

Abstract: An apparatus and process is provided for electromagnetically casting molten material into a desired shape. A containment zone is established. The containment zone has a first section for electromagnetically containing the molten material and a second section downstream and communicating with the first section for forming the molten material into the desired shape. The improvement comprises a heat extraction device for directing a cooling medium into the containment zone whereby the cooling medium passes the molten material in the second section to rapidly solidify the molten material prior to passing the molten material in the first section to lower the temperature in the contained molten material to minimize superheating. A second embodiment of the invention includes a secondary cooling device associated with the heat extraction device for directing a cooling medium against the solidified material.

Abstract: A process and apparatus for casting a material into a desired thin strip shape. Molten material is formed into the thin strip shape by an electromagnetic containing and forming process. In a first portion the molten material is shaped into the desired thin strip shape and in a second portion upstream of and communicating with the first portion the molten material is electromagnetically contained in a sump. The sump at a top surface thereof has a substantially larger cross-sectional area as compared to a cross-sectional area of the thin strip shape.

Abstract: A method and apparatus for electromagnetic casting of metal and alloy ingots of desired shape having portions of small radius of curvature. A modified shield is provided which provides for a reduction of the electromagnetic field intensity at the corners of the forming ingot by increasing local screening of the field at the corners. Increased local screening at the corners is achieved by locally increasing shield depth, by providing for deeper displacement of the shield, by changing the shield section, or by changing the shield orientation. Also disclosed is a modified inductor which is shaped so as to be located at a greater distance from the portions of small radius of curvature of the ingots than from portions of the ingots adjacent to the portions of small radius of curvature. The modified shield may be combined with the modified inductor and/or with a coolant manifold to simultaneously modify and control coolant application elevation such that the elevation is a minimum at the corners of the ingot.

Abstract: A mold for electromagnetic continuous casting has a supporting frame for an induction coil and a cooling device which features at least one nozzle for directing a liquid coolant onto the surface of the ingot being cast. A section (15) is provided in line with the stream of liquid coolant emerging from at least one nozzle such that it provides an impacting surface for deflecting the stream of coolant onto the surface of the ingot.

Abstract: An apparatus for casting metals wherein the molten metal is contained and formed into a desired shape by the application of an electromagnetic field. A control system is utilized to minimize variations in the gap between the molten metal and an inductor which applies the magnetic field. The gap or an electrical parameter related thereto is sensed and used to control the current to the inductor.