Abstract: In a process for melting metal chips, the process being of the type that uses a charge system for delivering the metal chips to a melt furnace, and of the type that uses a pre-treatment system for drying the metal chips, the improvement comprising the step of capturing an exhaust stream from the charge system, where the exhaust stream includes hydrocarbons, and combusting the hydrocarbons to produce heat that is utilized in drying the chips.

Abstract: In a process for melting metal chips, the process being of the type that uses a charge system for delivering the metal chips to a melt furnace, and of the type that uses a pre-treatment system for drying the metal chips, the improvement comprising the step of capturing an exhaust stream from the charge system, where the exhaust stream includes hydrocarbons, and combusting the hydrocarbons to produce heat that is utilized in drying the chips.

Abstract: In a process for melting metal chips, the process being of the type that uses a charge system for delivering the metal chips to a melt furnace, and of the type that uses a pre-treatment system for drying the metal chips, the improvement comprising the step of capturing an exhaust stream from the charge system, where the exhaust stream includes hydrocarbons, and combusting the hydrocarbons to produce heat that is utilized in drying the chips.

Abstract: A metal melting closed furnace which includes a main chamber, a circulation well connected to the main chamber by a communications passageway and a vortex well having a exit outlet for molten metal into the main chamber. A cover is emplaced over the vortex well. An inert gas bubble activated molten metal pump is provided in which there is an entry port in the circulation well and exit port into the vortex well. The exit port is positioned to lie at least partially or entirely above the maximum level of molten metal in the vortex well. This exit port will typically be at or near the top of the vortex well. In order to reduce oxidation, inert gas bubbles are captured from this molten metal pump and creating an inert gas atmosphere or blanket above the molten metal vortex.

Abstract: A metal melting closed furnace which includes a main chamber, a circulation well connected to the main chamber by a communications passageway and a vortex well having a exit outlet for molten metal into the main chamber. A cover is emplaced over the vortex well. An inert gas bubble activated molten metal pump is provided in which there is an entry port in the circulation well and exit port into the vortex well. The exit port is positioned to lie at least partially or entirely above the maximum level of molten metal in the vortex well. This exit port will typically be at or near the top of the vortex well. In order to reduce oxidation, inert gas bubbles are captured from this molten metal pump and creating an inert gas atmosphere or blanket above the molten metal vortex.

Abstract: A metal melting closed furnace which includes a main chamber, a circulation wall connected to the main chamber by a communications passageway and a vortex well having a exit outlet for molten metal into the main chamber. A cover is emplaced over the vortex well. An inert gas bubble activated molten metal pump is provided in which there is an entry port in the circulation well and exit port tangentially arranged with respect to the periphery of the cavity. This exit port will typically be at or near the top of the vortex well. In order to reduce oxidation, inert gas bubbles are captured from this molten metal pump and are transported to an inert gas atmosphere or blanket above the molten metal vortex.

Abstract: An inert gas bubble-actuated molten metal pump, for the movement of molten metal in a molten-metal bath, which obviates the necessity of a heatproof and flameproof cover to counteract splashing and spattering at the surface of the molten metal bath above the pump, comprising an inert gas diffusion means at an upper end thereof, the diffusion means having an upper surface containing a multiplicity of small upwardly-opening apertures for the breaking up of large bubbles and the diffusion of small bubbles of inert gas upwardly therethrough. The pump includes a refractory block which comprises a conveying conduit which is preferably elongated in width and a spreader cavity in communication with both a passageway in the block for providing a source of inert gas and a lower end of the conveying conduit.

Abstract: The charge well of a metal melting furnace is provided with an internal cavity having a circular cross section when viewed from the top, preferably a cavity of cylindrical or conical configuration, and with a peripheral exit port located tangentially with respect to said cavity at a lower level thereof for exit of molten metal into the main chamber of the furnace. An inert gas bubble-actuated molten metal pump brings molten metal from a hotter section of the furnace, advantageously directly from the main chamber, and has its exit port located tangentially to the periphery of the cavity at an upper level thereof, thereby creating vortical flow of molten metal within the charge well for the more rapid and efficient melting of metal chips and scraps into the molten metal therein and for circulation of hotter molten metal throughout the furnace.

Abstract: An inert gas bubble-actuated molten metal pump is located between one section of a metal-melting furnace and a second section to pump molten metal from the one section, wherein the molten metal is at a higher temperature, into the second section, wherein the molten metal is at a lower temperature, and its effluent is directed into contact with metal chips being charged into the second section, thereby assisting in the more rapid melting of the chips into the molten metal mass in the second section. The inert gas employed to actuate the molten metal pump is captured beneath a heat-resistant and flame-resistant cover located above the exit port of the pump and over a substantial portion of the molten metal mass in the second section, thereby providing a non-oxidizing atmosphere at the surface of the molten metal mass or pool beneath said cover.

Abstract: Mass flow gravity feed furnace charger apparatus includes (1) a charge-well cover having an aperture and (2) an essentially vertical conduit for forming a substantially vertically-oriented column of metal chips or scrap within and above the aperture, and (3) structure for bringing both (1) and (2) into position above a charge well. The conduit is rapidly moveable up and down to force the metal chips or scrap into molten metal in the charge well even when the dross level at the surface of the molten metal is considerable, so that the apparatus and corresponding method permit charging when gravity feed alone is not sufficient or sufficiently rapid. In a preferred embodiment, the conduit has an interior surface provided with gripping means to assist with the downward movement of metal chips or scrap into the molten metal in the charge well when the up and down motion of the conduit is in effect.

Abstract: An inert gas bubble-actuated molten metal pump is located in a metal-melting furnace to effect circulation of molten metal throughout the furnace. The inert gas employed to actuate the molten metal pump is captured beneath a heat-resistant and flame-resistant cover located above the exit port of the pump and over a substantial portion of the molten metal, thereby to prevent splashing, spattering, and disruption of a thin protective layer or skin of oxidized metal at the surface of the molten metal as well as to provide a non-oxidizing atmosphere at the surface of the molten metal beneath said cover. In this manner and by this combination, the inert gas is employed most efficiently and economically.

Abstract: A method, for the conveyance of molten metal from one place to another, in a high-temperature molten metal pool in a metal-melting furnace or out of said molten metal pool, employing an at least partially-inclined elongated conveying conduit and gas feed means for feeding inert gas into the lower end of the conveying conduit and thereby inducing a flow of molten metal in and through said conveying conduit, is disclosed, along with suitable apparatus for carrying out the said method wherein the parts or elements coming into contact with the high-temperature molten metal pool are of a suitable refractory material. According to the present invention, the inert gas is fed into the conveying conduit at a supersonic velocity, thereby simultaneously effecting a degassing of the molten metal while it is being conveyed.

Abstract: A mass flow gravity feed furnace charger comprises a vertically-oriented elongated hollow conduit which is associated with an apertured heat-resistant charge-well cover adapted to lie essentially in contact with the upper surface of a molten metal pool in the charge well of a metal-melting furnace. Presized scrap metal charged into the conduit collects atop the surface of the molten metal pool, since the bottom opening of the conduit communicates with the charge-well cover aperture and permits the metal scrap to fall by gravity directly into the molten metal in the charge well. When the weight of the metal scrap column is sufficient to offset the resistance of the upper surface of the molten metal pool, the weight of the collected metal scrap gravitationally forces it into the molten metal mass where it melts and is assimilated.

Abstract: A method, for the conveyance of molten metal from one place to another, in a high-temperature molten metal pool in a metal-melting furnace or out of said molten metal pool, employing an at least partially-inclined elongated conveying conduit and gas feed means for feeding inert gas into the lower end of the conveying conduit and thereby inducing a flow of molten metal in and through said conveying conduit, is disclosed, along with suitable apparatus for carrying out the said method wherein the parts or elements coming into contact with the high-temperature molten metal pool are of a suitable refractory material. According to the present invention, the inert gas is fed into the conveying conduit at a supersonic velocity, thereby simultaneously effecting a degassing of the molten metal while it is being conveyed.

Abstract: A method, for the conveyance of molten metal from one place to another, in a high-temperature molten metal pool in a metal-melting furnace or out of said molten metal pool, employing an at least partially-inclined elongated conveying conduit and gas feed means for feeding inert gas into the lower end of the conveying conduit and thereby inducing a flow of molten metal in and through said conveying conduit, is disclosed, along with suitable apparatus for carrying out the said method wherein the parts or elements coming into contact with the high-temperature molten metal pool are of a suitable refractory material. According to the present invention, the molten metal is alloyed simultaneously with its conveyance, the same inert gas being employed for both conveying the molten metal and for entrainment of the alloying metal.

Abstract: A method, for the conveyance of molten metal from one place to another, in a high-temperature molten metal pool in a metal-melting furnace or out of said molten metal pool, employing an at least partially-inclined elongated conveying conduit and gas feed means for feeding inert gas into the lower end of the conveying conduit and thereby inducing a flow of molten metal in and through said conveying conduit, is disclosed, along with suitable apparatus for carrying out the said method wherein the parts or elements coming into contact with the high-temperature molten metal pool are of a suitable refractory material. According to the present invention, the molten metal is alloyed simultaneously with its conveyance, the same inert gas being employed for both conveying the molten metal and for entrainment of the alloying metal.

Abstract: A method, for the conveyance of molten metal from one place to another, in a high-temperature molten metal pool in a metal-melting furnace or out of said molten metal pool, employing an at least partially-inclined elongated conveying conduit and gas feed means for feeding inert gas into the lower end of the conveying conduit and thereby inducing a flow of molten metal in and through said conveying conduit, is disclosed, along with suitable apparatus for carrying out the said method wherein the parts or elements coming into contact with the high-temperature molten metal pool are of a suitable refractory material. According to the present invention, an intermittent or pulsating inert gas feed is employed to produce essentially spherical or cylindrical bubbles within the conveying conduit, thereby resulting in greater efficiency and economy because of the possibility of reducing the quantity of inert gas employed to induce the flow of an identical amount of molten metal.

Abstract: Utilization of metal chips, especially scrap metal chips, particularly brass and aluminum, by introduction of the metal chips into a pool of molten metal of which they are formed or an alloy thereof, with minimization of fuel cost, heat loss, and minimal conversion of the metal at the surface of the molten metal pool to metal oxide, as well as an increase in the yield of utilizable metal from the remelting or recycling operation, by maintaining a non-oxidizing atmosphere at the surface of the molten metal pool and optionally utilizing vaporized residual impurities from chips being recycled such as oil, lacquer, or similar vaporizable impurity to assist in maintaining the non-oxidizing atmosphere, thereby permitting elimination of impurity-removal steps previously required for preparation of the chips for recycling by introduction into such a molten metal pool, and thereby also conveniently and simultaneously substantially reducing environmental pollution from vaporizable contaminants, fumes, and decomposition

Abstract: A method, for the conveyance of molten metal from one place to another, in a high-temperature molten metal pool in a metal-melting furnace or out of said molten metal pool, employing an at least partially-inclined elongated conveying conduit and gas feed means for feeding inert gas into the lower end of the conveying conduit and thereby inducing a flow of molten metal in and through said conveying conduit, is disclosed, along with suitable apparatus for carrying out the said method wherein the parts or elements coming into contact with the high-temperature molten metal pool are of a suitable refractory material.

Abstract: Apparatus and method for charging metal chips into a molten bath of the metal from which the chips are formed, comprising a compacting extruder and a delivery conduit which is resistant to the mass of molten metal and which is pivotable to dip into the molten metal bath when chips are being charged thereinto and out of contact with the bath when charging is to be discontinued, are disclosed. The chips are forced through the delivery conduit in the form of a compacted or densified mass preferably having a density between about 30 and 60 percent of the density of the solid metal and preferably between about 55 and 80 pounds per cubic foot. Feed is continued while the delivery conduit is in the molten metal bath and until it is removed therefrom to prevent entry of molten metal into the delivery conduit. The method is preferably conducted on a continuous basis and various sensors with appropriate wiring may be employed for safety and for making the method substantially automatic in operation.