Abstract: A method of adding gasses to, and removing gasses from a molten metal is disclosed. A molten metal is passed from a metal making furnace and cascaded through a gas or a flame. The flame is generated by a combustion burner and has an inner core of a first gas and an outer core of a second gas which jackets the first gas. As the metal is cascaded through the flame or gas, the first gas is passed into the molten metal. In the alternative, the cascade of molten metal may be passed through the first gas, or the first gas may be mixed with molten metal. The first gas may be used to sparge, react with, degassify, or otherwise dissolve within the molten metal. The device of the invention comprises a vessel for receiving the molten metal, a transfer trough extending from the furnace toward the vessel, and a combustion burner positioned with respect to the transfer trough and the vessel.

Abstract: A molten metal transfer pipe 52 for transferring an injection sleeve 51 has a bent pipe portion 3 thereof reduced in diameter to provide a throttle part 4 attaining a pressure loss effect. A melting and holding furnace 101 with a tilting mechanism has a melting and holding furnace section 101 and an electrical lifter 113 for holding the melting and holding furnace section 101 horizontally and for tilting the melting and holding furnace 101 together with a molten metal supplying apparatus 102 upwardly about the melting chamber 104 serving as a tilting fulcrum C to hold the same in the tilted position.

Abstract: Process and a device for producing metal powders from molten metal. The process includes directing at least three successive gas beams at a molten metal stream inside an atomization chamber, the at least three gas beams being oriented in different directions. The device includes a metallurgical vessel for holding molten metal provided with a nozzle element for discharging a molten metal stream into an atomization chamber as well as at least three gas nozzle elements for providing at least three gas beams of different orientation and directed at different points of the molten metal stream inside the atomization chamber.

Abstract: Fume dust is prevented when molten metal is poured into a vessel, and water or water mist is sprayed into the vessel or onto the molten metal, creating a reduced level of oxygen concentration of about 12% by volume, preferably about 8% by volume, inside the vessel or at the molten metal surface.

Abstract: The invention relates to a process for transferring liquid metal, in particular steel, between an upstream container and a downstream container through a tapping spout of a set of refractory assemblies. The assemblies include at least one mating surface having a shroud channel surrounding the tapping spout. The process includes injecting inert gas and, when desired or necessary, a sealing agent into the shroud channel. The sealing agent is adapted to seal leaks in the shroud channel, thereby reducing aspiration of air into the liquid metal.

Abstract: A stopper for continuous casting comprising a stopper rod and a spindle for actuating the stopper rod, wherein the stopper rod includes a joining nut integrally formed therewith, an upper end surface of the stopper rod being formed so as to be smooth, and a pin hole being provided in the upper end surface so as to prevent from rotating, while the spindle includes a gas introduction route, a male screw provided in a tip portion thereof for being engaged with the joining nut, a male screw provided in an upper portion thereof for being engaged with a fastening nut for fixing the spindle to the stopper rod, and a flange tightly adhered to the upper end surface of the stopper rod and provided with a hole, into which a pin for preventing rotation is inserted. The spindle is fixed to the stopper rod by the joining nut. The flange is fixed to the upper end surface of the stopper rod by the fastening nut so as to be hermetically sealed.

Abstract: A slide gate plate throttling mechanism for the continuous casting of molten metal includes a gate plate assembly. The gate plate assembly is connected to an upper nozzle disposed below a vessel for containing molten metal and is disposed above an elongated lower nozzle that directs flow of molten metal. Each plate of the gate plate assembly includes an opening that forms a portion of a passageway for the molten metal. The gate plate assembly comprises a gate plate that is moved so as to open and close the passageway, a lower plate connected to an upper surface of the nozzle, and a groove disposed in a bottom surface of the lower plate around the lower plate opening. The mechanism further comprises at least one control device for regulating flow of inert gas and graphite into the groove. The system may include a device for measuring back pressure in the groove to determine when to seal the groove by injecting graphite therein.

Abstract: The invention relates to a plant for transferring liquid metal, in particular steel, between an upstream container (2) and a downstream container (10), comprising: an upstream container (2); a tapping spout (28); a downstream container (10), a flow regulator (26) for regulating the flow of liquid metal through the tapping spout (28); a set of refractory assemblies (8, 12, 30, 32, 64, 66, 74) which are placed between the upstream container and the downstream container, delimiting the tapping spout (28) via which the liquid metal flows from the upstream container (2) into the downstream container (10), each refractory assembly of the tapping spout (28) having at least one mating surface (22) forming a joint with a corresponding surface of an adjacent refractory assembly; a shroud channel (18; 40) placed around the tapping spout (28) near at least one mating surface (22) between refractory assemblies (8, 12, 30, 32, 64, 66, 74), this shroud channel having an inlet (44) capable of allowing the introduction of mat

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: A process in which, during the flow of molten metal in a conduit an inert gas and oil are injected at the position of the joint plane between two refractory parts in such a manner as to prevent the introduction of gases from the atmosphere into this conduit at the position of the joint plane. Apparatus. Advantages: plugging of leaks at the position of the joint plane, lower inert gas consumption absence of degradation of the quality of the molten metal by the inert gas.

Abstract: A caster including a device for delivering a gas into a space created by the apparatus that define the mold of the caster and the nozzle of the caster. Introducing a gas into the space resists backflowing and freezing of the molten metal to the nozzle.

Abstract: A refractory slide-gate plate including a refractory base plate which is designed in a ring shape or so as to have a recess portion on a surface thereof, a refractory plate member which is fixedly engaged with the inside of the ring-shaped refractory base plate or with the recess portion of the refractory slide-gate to be integrated with the refractory base plate, and an inert gas supply groove comprising a step portion which is formed in 2 to 20 mm width and in 2 to 20 depth on at least one of the inner peripheral portion of the ring-shaped refractory base plate and the inner peripheral portion of the recess portion. The refractory plate member is preferably formed of Al.sub.2 O.sub.3 --ZrO.sub.2 --C-based refractory material or ZrO.sub.2 -based refractory material.

Abstract: A refractory block for continuous casting comprising: a unitary assembly comprising: a plate brick having a top, a bottom, sides and a passageway therethrough, and a submerged nozzle having a top, a bottom, sides and a passageway therethrough, the sides of the submerged nozzle having a shoulder portion, the bottom of the plate brick joining the top of the submerged nozzle; a metal casing surrounding the unitary assembly such that the metal casing surrounds and supports a portion of the sides of the plate brick, a portion of the bottom of the plate brick and a portion of the sides of the submerged nozzle including the shoulder portion, and an air cooling jacket surrounding the metal casing.

Abstract: The present invention pertains to a snorkel for a degassing vessel, with a refractory lining and a gas-purging device arranged therein with a plurality of channels, which, distributed over the circumference of the snorkel, extend through the refractory lining in the radial direction in relation to the central longitudinal axis of the snorkel and can be connected on the outside to at least one gas supply line.

Abstract: The invention provides continuously-cast product free of ambient atmosphere contaminants and free of nonmetal solid entrapment. Methods and apparatus are provided for flow of molten metal from ladle to tundish to mold machine, free of contact with ambient atmosphere; and, tundish slag cover is removed, by discharge of a nonreactive gas to provide a selected limited surface area of tundish metal, which is free of slag cover, for insertion of a ladle shroud to deliver molten metal, free of entrapment of nonmetal slag cover, for continuous casting. Transitional casts, before clean metal is obtainable with each new ladle of molten metal, are eliminated; and the duration of uninterrupted continuous casting of clean metal is extended.

Abstract: The present invention relates to a long nozzle used to prevent molten steel flowing out of a collector nozzle of a sliding nozzle from being oxidized by atmospheric air when molten metal, particularly molten steel is poured from a ladle into a tundish. This nozzle has a construction comprising: (a) the long nozzle (3) made of a refractory causes molten metal to flow down from the collector nozzle (2) and the head thereof is covered by a metallic shell (16); (b) a first gas passage is provided to blow inert gas to the vicinity of a fitting portion (7) between the collector nozzle (2) and the long nozzle (3) through a first gas inlet port (8) provided on the side wall of the metallic shell (16); and (c) a second gas passage is provided to blow inert gas into an inner hole (18) of the long nozzle through a second gas inlet port (10) provided on the side wall of the metallic shell (16).

Abstract: A gas flushing device for a blowpipe of a degassing vessel, the blowpipe being cladded with a fire resistant material. The gas flushing device has a plurality of channels which are distributed around the circumference of the blowpipe and pass through the fire resistant cladding radially in relation to the central longitudinal axis of the blowpipe and can be connected on the outside to at least one gas feed pipe. The channels are between 0.5 and 2 mm in diameter, are spaced at intervals of less than 10 mm and can be pressurized in such a way that the gas on entering the blowpipe rises in the immediate vicinity of the blowpipe inner wall.

Abstract: Argon injection nozzles are provided in a close-spaced series lengthwise along a treatment trough, in which liquid aluminum is conveyed. The gas is blown in at high Reynolds No, whereby the jets break up into small bubbles. A high average bubble population density is achieved over the whole volume of liquid metal in the treatment trough. De-gassing is achieved in a metal residence time of 15 to 60 seconds, whereby the trough in which treatment takes place can be small.

Abstract: A sealing system for the engagement of a container (24) beneath a melting pot containing a molten material, comprising a shell (30) surrounding a nozzle (40), the nozzle being located in the axis of the neck of the container and permitting the pouring of the material from the melting pot into the container. The shell (30) has tight connection means with the nozzle (40), a base (32) having a bearing surface for the reception of a corresponding bearing surface on the container neck and at least one bellows (33, 34) surrounding the nozzle and connecting the tight connection means to said base, the bellows being able to render the shell retractable along the nozzle axis, means for introducing a gas flow between said bearing surfaces being provided in order to permit the circulation of part of said flow towards the nozzle.

Abstract: The present invention provides a nozzle for teeming molten metal, particularly molten steel, from a tundish or other receptacle, which nozzle comprises an inlet, an outlet, and inner and outer tubular members which define a bore through the nozzle between the inlet and outlet. The nozzle is characterised in that both of said inner and outer tubular members are constructed from refractory materials, and in that the inner member extends within the outer member to the inlet. The inner and outer ceramic layers thus form a "double-layer" of refractory material up to the extremity of the nozzle at the inlet end.

Abstract: A refractory nozzle assembly is provided that effectively prevents the accumulation of alumina deposits around its upper edge where it receives a stopper rod. The nozzle assembly includes a refractory nozzle body having an upper and a lower portion. A bore extends through both the upper and lower portions that has a receiving and a discharge end for receiving and discharging molten metal. An inert gas distributor circumscribes the upper portion of the nozzle body. A sleeve of gas-obstructing refractory material covers the walls of the bore, and defines a seat portion at an upper portion of the bore. A metal sheath substantially surrounds the outer surface of the upper portion. Pressurized inert gas conducted to the upper, gas permeable portion of the nozzle body by the gas-distributing assembly is guided by the gas-obstructing sleeve and the metal sheath so that it flows predominantly through the top edge of the upper portion.

Abstract: A closure and/or regulation apparatus for controlling the outflow of melt from a metallurgical vessel includes a stator and a rotor rotatable relative to the stator. Additional responsive control of outflow is provided by a chamber that is part of or is connected to an outflow channel that can be connected to a vacuum generator.

Abstract: A process for reducing dust emission and free air access in the tapping region of a blast furnace by applying CO.sub.2 in a solid and/or gaseous state to the molten material and or the runners and vessels associated therewith. This process reduces dust emissions, nitriding of the product and energy costs associated with conventional dust reduction operations as well as wear of the refractory materials.

Abstract: Ingress of gas such as air through the joint of a pour tube and tube holder of a continuous caster is prevented or inhibited by passing an inert gas into a circumferential channel around the orifice and at the interface of the joint; the gas is evenly distributed within the channel over the entire configuration of a porous refractory insert in the circumferential channel; the porous refractory insert assures even distribution of the gas to the desired location in the joint.

Abstract: In the continuous casting of steel, gas is prevented or inhibited from contacting molten steel through the valve slide plate by feeding inert gas through channels in the slide plate and adjacent parts; the channels contain porous refractory inserts and can be connected to outside sources through juxtaposed side channels.

Abstract: A system and device for removing impurities from molten metal comprising a pump within a chamber having an outlet port. The pump creates a flow or stream of molten metal through the outlet port. One or more gas-release tubes are provided adjacent the outlet port, each gas-release tube having one or more gas-release openings adjacent the outlet port. Gas is introduced into the gas-release tube(s) whereby it escapes through the openings into the molten metal stream thereby removing impurities from the molten metal. The system may further comprise a gas-release block, having one or more openings, mounted adjacent the bottom of the outlet port, partially within the molten metal flow. Gas is introduced into the block through a gas-transfer device where the gas escapes through the openings and enters the lower portion of the molten metal stream. Finally, the system may further comprise a metal-transfer device for containing the molten metal stream.

Abstract: A bubble-operated pump for recirculating molten metal in a bath of such metal.

Abstract: An apparatus for mixing a particulate substance, which may be in chopped or short fibre form, with a matrix metal comprises a container (11) for molten metal (10) having an aperture (12) through which a stream of the metal can fall, a feed motor (20) for feeding the particulate substance into the metal stream, and one or more downwardly inclined nozzles (23) through which jets of atomizing gas are directed on to the combined flow of metal and particulate substance. The feed motor comprising a horizontal ring (20a) which extends about and is coaxial with the molten metal stream, and which has a radial vibration imparted to it so as to form a node on the axis of the ring. The upper surface of the ring may be horizontal or may be inclined downwardly towards the axis and may have annular grooves of ratchet tooth section with the steeper part of the section facing towards the axis.

Abstract: A refractory block for continuous casting is disclosed comprising a unitary assembly including a plate brick having a top, bottom, sides and a passageway therethrough; a gas permeable porous brick having a top, bottom, sides and a passageway therethrough, where the top of the porous brick is attached to the bottom of the plate brick, a gas pool for containing gas surrounds the sides of the porous brick, and a submerged nozzle having a top, bottom and sides, where the sides have shoulder portions, has the top of the submerged nozzle attached to the bottom of the porous brick. A metal casing surrounds the unitary assembly so that the metal casing surrounds and supports a portion of the sides of the plate brick, a portion of the bottom of the plate brick, the sides of porous brick, and a portion of the sides of the submerged nozzle, including the shoulder portions. The metal casing further includes gas feed and discharge pipes therethrough in communication with the gas pool.

Abstract: This invention relates to an inert gas injecting plate brick or nozzle brick for use in a sliding gate valve apparatus of molten metal, characterised in that said plate brick or insert nozzle brick is horizontally split into at least two parts, and a number of small diameter pipes are sealingly arranged and secured in said split surfaces. According to such a plate brick or nozzle brick, it is possible to prevent leakage of injection gas in such kind of apparatus, it is possible to carry out a stable casting working, and complicated, high cost, additional processes such as cutting working, boring working and connecting working of said bricks can be saved.

Abstract: Close-coupled atomization systems and methods employing axisymmetric fluid flow and non-axisymmetric melt guide tube exit orifice configuration have demonstrated superior efficiency in the production of fine superalloy powder, such as, for example, nickel base superalloys compared to conventional close-coupled atomization utilizing an axisymmetric annular gas orifice and an axisymmetric guide melt guide tube exit orifice configuration.

Abstract: Close-coupled atomization systems and methods employing non-axisymmetric gas flow have demonstrated superior efficiency in the production of fine superalloy powder, compared to conventional close-coupled atomization utilizing an axisymmetric annular gas orifice and an axisymmetric melt nozzle. A means has been devised for convening otherwise axisymmetric plenums into non-axisymmetric plenums that produce non-axisymmetric gas flow.

Abstract: The object of the present invention is to provide a gas injection nozzle which is used for pouring liquid metal and which is prevented from being blocked in the course of continuous casting. According to the present invention, a gas injection nozzle for pouring liquid metal is provided, wherein(a) the nozzle consists of a porous refractory,(b) the circumference of the nozzle is surrounded by an iron shell which has a gas injection pipe, a band-like space (referred to as a gas pool hereinafter) which extends along the circumference of the nozzle perpendicular to an axis of the nozzle between the porous refractory and the iron shell, and(c) the gas pool is formed as a wavy, band-like space along at least one portion of the circumference of the nozzle.

Abstract: An apparatus and method for atomizing liquid metal are disclosed. A liquid metal supply is coupled to a nozzle for atomizing a stream of liquid metal in an atomizing zone extending from the nozzle. A viewing instrument provides a field of view extending to the atomization zone. A sensor coupled with the viewing instrument generates an image of the atomizing zone, and a control adjusts a flow rate of the stream responsive to the image.

Abstract: An apparatus, system and method for viewing an industrial process in an obscuring environment, such as molten metal atomization, is disclosed. An enclosure defining a chamber for containing a particulate form from atomized liquid metal has a nozzle for atomizing liquid metal mounted thereon in communication with the chamber whereby particles recirculate throughout the chamber. The nozzle being comprised of a cylindrical plenum means and a melt guide tube extending axially therethrough to an exit orifice. The plenum means is configured to provide a jet of atomizing gas converging in an atomizing zone extending from the exit orifice. A viewing means extends through the enclosure to a viewing orifice adjacent the atomization zone, the viewing means being configured to extend a field of view through the chamber to the atomization zone.

Abstract: A method and apparatus for blanketing the surface of material, e.g. molten metal contained in an open top vessel, e.g. induction furnace, by establishing a swirling flow of an inert gas having a density greater than air at the top of the vessel. Inert gas exits the swirl flow through an opening in a flow controlling apparatus having an exit opening with a diameter that is smaller than the base diameter of the swirl adjacent the open top vessel.

Abstract: A regulating gas flow valve is operatively connected to an oscillating molten metal spray forming ring converter through which a molten metal stream passes. The passing metal stream is impacted by gas jets from the converter which breaks up the metal stream into a spray pattern of small molten metal droplets. The valve regulates the flow of gas into the converter as a function of the converter oscillation which also operates the valve.

Abstract: A reinforced ceramic tube for refractory use comprises a settable slurry cast inside a metal sleeve with longitudinal, compliance. In use the sleeve moves with ceramic under thermal stress to avoid major cracking.

Abstract: A nozzle for an electric dispersion reactor includes two concentric electrodes, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode.

Abstract: A unitized nozzle and top plate assembly for use in a slide gate valve is disclosed which comprises a nozzle having porous, gas permeable walls, a top plate having an opening through its thickness for regulating a flow of molten metal, such as steel, and a recess circumscribing the opening for receiving and securing the discharge end of the nozzle to the top plate. The depth of the recess is at least 50%, and preferably 70-80% of the thickness of the top plate in order to minimize the contact between molten metal and the surface of the top plate opening, which in turn reduces the amount of flow-obstructing alumina deposits which accumulate in this area of the slide gate valve. To prevent leaks from occurring in the system supplying pressurized argon through the porous nozzle walls, the gas coupling that is normally welded directly to the steel can surrounding the nozzle is instead mounted on the end of a steel pipe connected to the can.

Abstract: Melt atomizing apparatus comprising a melt supply orifice for supplying the melt for atomization and gas supply orifices proximate the melt supply orifice for supplying atomizing gas to atomize the melt as an atomization spray. The apparatus includes a sensor, such as an optical and/or audio sensor, for providing atomization spray data, and a control unit responsive to the sensed atomization spray data for controlling at least one of the atomizing gas pressure and an actuator to adjust the relative position of the gas supply orifice and melt supply in a manner to achieve a desired atomization spray.

Abstract: A gas-shielded siphonic valve for controlling the flow of molten metal from one vessel to another. The valve includes a hollow conduit extending between the vessels above the surfaces of the metal therein with opposite ends thereof immersed in the metal in both vessels. An exhaust port permits evacuation of the inside of the conduit sufficiently to draw enough metal up into the conduit to effect a siphoning action between the vessels. A housing surrounding the conduit defining a chamber about the conduit for holding an inert gas. Any leaks in the system will neither break the siphoning action nor contaminate the metal. Varying the amount of vacuum applied to the system can be used to control the rate of flow of metal therethrough.

Abstract: Reactive metal granules, especially of magnesium and/or magnesium alloys, are produced directly from molten metal. The metal is fed under pressure to a granulation nozzle which forces the metal to acquire a circular motion of increasing velocity before it reaches the outlet of the nozzle and disintegrates successively into small fragments and droplets. These fragments and droplets are formed in an inactive gas atmosphere in an enclosed system and are thereafter solidified and cooled in a nonoxidizing cooling bath. An apparatus includes a granulation chamber made up of two parts which can be fitted to each other at various positions with an air tight locking system.

Abstract: A belt for sealing a discharge device of a ferrous-metallurgical vessel is formed by two concentric grooves formed in one and/or the other of a pair of superimposed sliding plates. A first, outer, groove (8) is connected to a vacuum source and a second, inner, groove (1) is connected to an inert-gas source.

Abstract: A sealing apparatus for shielding air from a path of molten steel in a laddle to a tundish in continuous metal casting facilities to prevent oxidation of the molten metal, the apparatus including a seal box lift mechanism mounted on a tundish body through a bracket and including a drive member and a lift rod member to be vertically moved up and down by the drive member; a seal box including an outer cylinder fixedly mounted on a tundish cover and extending into the tundish, and an inner cylinder telescopically fitted in the outer cylinder and connected to the lift rod member through a lever; a first seal member fixed at the upper end of the inner cylinder and pressed against a nozzle mounting surface of the laddle when the inner cylinder is lifted up by the lift rod member; a second seal member fixed on the outer cylinder to seal gap space between the outer and inner cylinders; and an inert gas inlet provided in the wall of the inner cylinder.

Abstract: The invention relates to a plug made of refractory material for a metallurgical casting vessel. The plug 5, which can be formed with a central axial channel 5b, has an axial channel 5d which terminates eccentrically in front of the plug cap 5a and which is disposed in an axially extending rib 5c formed on the plug 5. A thermocouple 6 with its measuring cables is accommodated in said further axial channel 5d.

Abstract: A method for the electroslag refining of titanium base alloy is provided. The method involves providing a refining vessel to contain an electroslag refining layer floating on a layer of molten refined metal. An ingot of unrefined titanium base alloy having a higher nitrogen content is lowered into the vessel into contact with the molten electroslag layer. A refining current is passed through the slag layer to the ingot to cause surface melting at the interface between the ingot and the electroslag layer. As the ingot is surface melted at its point of contact with the slag, droplets of the unrefined metal are formed and these droplets are refined as they pass down through the slag and are collected in a body of molten refined metal beneath the slag. The refined metal is held within a cold hearth. At the bottom of the cold hearth, a cold finger orifice is provided to permit the withdrawal of refined metal from the cold hearth apparatus.

Abstract: A pressure-casting machine that contains a delivery system, which comprises: a molten metal pouring pipe made of a refractory, having a length of at least 4 m and an outside diameter of at least 350 mm, and arranged such that an upper end thereof is attached substantially vertically from below to an opening in a bottom wall of a mold for a pressure-casting machine, and a lower end thereof extends through a lid of a closed vessel arranged below the mold and is immersed into molten metal received in a ladle arranged in the closed vessel. The molten metal pouring pipe comprises at least two pipe sections connected to each other in series and in a liquid-tight manner by means of a threaded joint, tapered surfaces provided with screw threads of which have an inclination angle within a range of from 2.0.degree. to 15.0.degree. relative to the center axis of the molten metal pouring pipe.

Abstract: A gas flow distribution system for a solder dispensing head includes a base member adapted to be connected to the solder dispensing head and a structure connected to a source of an inert gas for distributing at least one continuous stream of the inert gas radially and axially below the solder dispensing head to exclude oxygen in the surrounding air therefrom.

Abstract: A method of atomization of refined metal is taught. The method starts with the introduction of unrefined metal into an electroslag refining process in which the unrefined metal is first melted at the upper surface of the refining slag. The molten metal in the form of droplets is refined as it passes through the molten slag. The refined metal droplets are collected in a cold hearth apparatus having a skull of refined metal formed on the surface of the cold hearth and protecting the cold hearth from the leaching action of the refined molten metal. A cold finger bottom pour spout is formed at the bottom of the cold hearth to permit dispensing of molten refined metal from the cold hearth. The rate of flow of molten metal through the cold finger apparatus is controlled principally by controlling the rate of melting of the unrefined metal. The metal flowing from the cold finger apparatus is introduced to the upper end of a ceramic melt guide tube.