Abstract: Disclosed herein are a graphite crucible for electromagnetic induction-based silicon melting and an apparatus for silicon melting/refining using the same, which performs a melting operation by a combination of indirect melting and direct melting. The crucible is formed of a graphite material and includes a cylindrical body having an open upper part through which a silicon raw material is charged into the crucible, and an outer wall surrounded by an induction coil, wherein a plurality of slits are vertically formed through the outer wall and an inner wall of the crucible such that an electromagnetic force created by an electric current flowing in the induction coil acts toward an inner center of the crucible to prevent a silicon melt from contacting the inner wall of the crucible.

Abstract: Thermoplastic pellitized materials are melted in gravity flow through coaxially oriented perforated cylindrical metal susceptors. The susceptors are equally energized by the interception of a common magnetic field formed by a high frequency powered inductor coil.

Abstract: A melting furnace including a sealed container containing an inert gas atmosphere, a crucible that is located inside the sealed container and melts a raw material by induction heating, and a crucible cooling mechanism. The crucible cooling mechanism includes a pipe portion that includes an intake that communicates with the sealed container and enables the inert gas to be discharged from the sealed container, and an outlet that enables the inert gas to be introduced into the sealed container, a heat exchange portion that is located partway along the pipe portion, and a gas transporting portion that is located partway along the pipe portion.

Abstract: Disclosed is a heating furnace system for hot stamping. A first heating furnace has a plurality of pairs of upper and lower rolls arranged in a lengthwise direction thereof in order to transfer a steel plate, and high-frequency coils alternately arranged with the pairs of upper and lower rolls in the lengthwise direction thereof. A second heating furnace continuously transfers the steel plate from the first heating furnace during heating the steel plate at temperature of Ac3 or more, and has a plurality of transfer rollers arranged in a lengthwise direction thereof. The second heating furnace includes an electric furnace or a gas furnace. This heating furnace system can reduce space required for facilities by 50% or more compared to the related art.

Abstract: Methods of operation of an induction melter include providing material within a cooled crucible proximate an inductor. A desired electromagnetic flux skin depth for heating the material within the crucible may be selected, and a frequency of an alternating current for energizing the inductor and for producing the desired skin depth may be selected. The alternating current frequency may be adjusted after energizing the inductor to maintain the desired electromagnetic flux skin depth. The desired skin depth may be substantially maintained as the temperature of the material varies. An induction heating apparatus includes a sensor configured to detect changes in at least one physical characteristic of a material to be heated in a crucible, and a controller configured for selectively varying a frequency of an alternating current for energizing an inductor at least partially in response to changes in the physical characteristic to be detected by the sensor.

Abstract: A method of operating an induction furnace so as to receive electric arc furnace (EAF) dust, basic oxygen furnace (BOF) sludge/dust and/or other iron and volatile metals containing materials as a feed stream on a batch, continuous or semi-continuous basis together with a iron-containing material feed, and therefrom produce an iron-containing hot metal or pig iron product while recovering iron value from the feed materials and recovering volatile metal components contained in the feed materials.

Abstract: A device for the melting or purifying of inorganic substances, in particular of glass, which comprises a number of metal tubes which may be attached to a cooling medium and which are arranged next to each other, in such a way that together they form a container, a high frequency coil for the injection of energy into the container contents and a plastic coating for the metal tubes, the decomposition temperature of which lies below the temperature of the melt. The cooling system is configured and arranged such that the temperature of the boundary layer of the melt, immediately surrounding the component, lies below that of the decomposition temperature of the coating material.

Abstract: A method of operating an induction furnace so as to receive electric arc furnace (EAF) dust, basic oxygen furnace (BOF) sludge/dust and/or other iron and volatile metals containing materials as a feed stream on a batch, continuous or semi-continuous basis together with a iron-containing material feed, and therefrom produce an iron-containing hot metal or pig iron product while recovering iron value from the feed materials and recovering volatile metal components contained in the feed materials.

Abstract: Protection systems are described for electrical systems such as electrical arc furnaces. The protection systems may be designed and used to detect and clear faults that may occur within the electric arc furnace. For example, a pair of Rogowski coils may be used to detect current at their respective locations along a conductors, and output corresponding signals to a multi-function, differential relay having multiple voltage and current inputs. By comparing the signals from the Rogowski coils, the differential relay may determine whether a fault exists at some point along the conductors and between the pair of Rogowski coils. Further, the relay may then, in response to the fault, trip a circuit breaker or other network protection device, so that the fault may be corrected.

Abstract: A process and apparatus assuring low costs and high efficiency in practicing refuse incineration. A applying electromagnetic wave of a frequency band resonant with rotation or vibration of a specific substance e.g., dioxins molecule, thereby to heat the dioxins molecule selectively up to high temperature to remove the dioxins molecule by decomposition.

Abstract: An environmentally controlled heating system for heating metal alloy billets wherein a trolley system carries the billets through the chambers of the induction heating system in crucibles that are pushed or pulled by actuators. The billets enter the system through a load-chamber and travel through a main chamber to a heating area where the loaded crucibles pass through a series of induction heating coils. The heated billets leave the heating area through a dump-chamber where they are delivered to a forming system. The empty crucibles reenter the main chamber and travel back to the loading area to receive another billet. The heating system is controlled through a computing device for monitoring and controlling the system, preferably a programmable logic controller. A vacuum system evacuates air from the chambers, and an inert gas system back-fills the chambers with an inert gas. A gettering system continually cleans the inert gas.

Abstract: A sealed evacuatable crucible (1) for inductive melting of metals or other electrically conductive materials, including a plurality of palisades (2,2', . . . ) which are arranged parallel to one another, and for enclosing the melt and forming the crucible wall, and having a crucible base part (3) which carries the palisades (2,2', . . . ), and having an induction coil (18) which is wound around the palisades (2,2', . . .

Abstract: An inductively heated drain tube fashioned of high temperature, electrically conducting materials is disclosed. An inductor surrounds the drain tube. The inductor and drain tube are cast within a refractory material. The drain tube is then placed in communication with the side of a bath of molten materials. When power is supplied to the inductor, the inductor couples with the drain tube, heating the drain tube and allowing it to act as a drain for high temperature molten materials. When power is removed from the inductor, a flow of cooling liquid through the inductor cools the drain tube, solidifying the molten materials and stopping their flow through the drain tube. The refractory material encases the inductor, acting as a thermal barrier and preventing damage from molten materials.

Abstract: An annular exhaust gas passage 2 and an airtight retention member 3 for keeping the inside of a crucible induction furnace 1 airtight are installed on the top of the furnace 1, and an exhaust system under atmospheric pressure is connected to a valve 4 via an air duct that penetrates the airtight retention member 3. In addition, a sealing cover 7 that has a valve 8, which can be opened and closed, is used to keep the inside of the furnace airtight, while a system under reduced pressure is connected to the valve 8. These two systems constitute the entire exhaust system.

Abstract: A method of refining molten metal includes the steps of reduced-pressure-refining molten metal in a heated vessel, adding slag-forming agents into the refined molten metal while keeping the molten metal in the vessel, or after pouring the molten metal into another vessel, re-refining the molten metal by heating the molten metal with inert-gas plasma and while stirring the molten metal as occasion demands. Preferably, the refining apparatus includes two adjacent chambers, each chamber isolated from the surrounding atmosphere. The chambers can be connected with, or separated from, each other and each chamber is provided with an exhaust device. One of the chambers is provided with an induction heating refining furnace, and the other chamber is provided with inert gas plasma heater. The apparatus also includes a re-refining vessel which is transferable between the two chambers, and a material feeder for feeding slag-forming agents into the re-refining vessel.

Abstract: A furnace system particularly adapted for use with a continuous upcaster. Instead of employing discrete furnaces, tundishes, ladles and the like, the instant unitary system employs a furnace, a feeding mechanism for directly introducing material into the furnace and a plasma torch to melt the material. The rate of material entering the furnace is balanced by the quantity of product emerging from the upcaster.

Abstract: Method of and apparatus for providing agitation of the melt in the induction melting of metals. A medium frequency melting power supply (12) of an induction furnace or crucible (10) acts in conjunction with a modulating circuit incorporating a wave form generator (14) whereby modulation at a predetermined amplitude and frequency is applied to the furnace power frequency during at least part of the melt processing cycle to cause agitation of the melt to a predetermined extent independently of the selected overall power input.

Abstract: A system for simultaneously melting metal and holding molten metal for casting operations and the like comprises a plurality of coreless induction furnaces. Each furance has an induction coil having a plurality of coil turns. The induction coils of the furances are arranged to inductively heat metal in the furnaces and are connected in electrical series. A single power supply furnishes AC power to the series-connected induction coils. Electrical taps are located on each induction coil at spaced intervals along the coil for enabling electrical connections to be made to the induction coils at said intervals. Each interval comprises a preselected number of coil turns. Switch means are associated with each induction coil and connected to selected ones of the electrical taps for selectably switching a preselected number of coil turns into and out of circuit with the power supply for selectively melting or holding molten metal in the induction furnace associated with a selected coil.

Abstract: The invention relates to a method for burning fine-grain material, particularly for the manufacture of cement clinker from cement raw meal. The material is thermally treated in a multi-stage burning process with a pre-heating stage, a calcining stage with a high-degree of calcination, a sintering stage in a very short rotary kiln and a cooling stage. Fuel is introduced both into the sintering stage in the short rotary kiln as well as into the calcinating stage. Hot exhaust air from the cooling stage is supplied both to the sintering stage as well as to the calcining stage as furnace air. The invention also relates to an apparatus for the manufacture of mineral products of the burning process such as cement clinker.

Abstract: The invention relates to a method for burning fine-grain material, particularly for the manufacture of cement clinker from cement raw meal. The material is thermally treated in a multistage burning process with a pre-heating stage, a calcining stage with a high-degree of calcination, a sintering stage in a very short rotary kiln and a cooling stage. Fuel is introduced both into the sintering stage in the short rotary kiln as well as into the calcinating stage. Hot exhaust air from the cooling stage is supplied both to the sintering stage as well as to the calcining stage as furnace air. The invention also relates to an apparatus for the manufacture of mineral products of the burning process such as cement clinker.