Abstract: This invention concerns a process for the reliable avoidance of slag contamination of the converter tapping steel by flush slag. In accordance with the invention a plastic, workable stopper made of fire-proof material containing silicic and oxidic components as well as suitable binding agents is used for this purpose. The stopper is introduced so far into the tapping channel with the help of a setting device that its front surface, terminated with a funnel-shaped compression plate, almost aligns flushly with the interior side of the converter, and it fills in the diameter of the tapping channel as a result of being compressed, creating such a plane that the flush slag occurring during tipping of the converter is reliably directed past the tapping channel. Stopper systems used up to now had the disadvantage that age-dependent enlargements of the tapping channel had a detrimental effect on the functioning of the stopper.

Abstract: A melting furnace for reforming steel-making slag so as to be available, for example, to roadbed ballast by mixing steel-making dust with the slag in molten states, which is provided with a fuel oxygen burner for melting the slag and the dust, a slag charging port for charging the slag in molten state into the furnace, a dust feeder for supplying the dust into the furnace, a slag feeder for supplying the slag in powdered state into the furnace, a storage portion for storing a molten mixture of the slag and the dust in a quantity corresponding to a tilting angle of the furnace body and an outlet port for discharging the molten mixture, and is possible to dispose the slag efficiently whether the slag is in the powdered or molten state.

Abstract: Tapping method for molten metal from containers (13) including at the lower part a tapping channel (14) associated at the end part with a discharge hole (15) substantially vertical or sub-vertical, the discharge hole (15) being associated at the lower part with a sliding interception device (19), wherein the tapping channel (14) comprises, associated with the walls, an electromagnetic device (17) with spirals (18) and a system for cooling the walls, wherein, during the end-of-tapping step of the liquid metal the sliding interception device (19) is activated by closing the discharge hole (15) and allowing the metal in the tapping channel (14) to solidify so as to form at least a layer which lines both the tapping channel (14) and the discharge hole (15) filling it completely, and that during the start-of-tapping step the sliding interception device (19) is activated by leaving the discharge hole (15) free and the metal which is blocking the discharge hole (15) is melted by means of the electromagnetic device (

Abstract: An apparatus and method relate to tapping a molten metal bath from a reactor. The apparatus includes a tapping pipe having a tapping pipe inlet and tapping pipe outlet for withdrawing a portion of the molten bath from the reactor. The molten bath can flow from the reactor through the tapping pipe inlet through tapping pipe to a tapping pipe exit. The tapping pipe is attached to the reactor at the tapping pipe inlet and the tapping pipe includes a susceptor, formed of a suitable material, such as graphite, which heats upon application of induction current. An induction coil assembly is annularly disposed about the tapping pipe, wherein the induction coil assembly can apply an induction current to heat the tapping pipe to a temperature that is higher than that of a solidified bath metal component within the tapping pipe. The induction current melts the solidified bath metal, whereby the molten metal bath can be tapped from the reactor.

Abstract: A process for closing a tap hole in a metallurgical vessel at least partially filled with a metal melt includes bringing a compressible fire-resistant material to the moth of a tubular closing element, providing a medium that substantially prevents contact between the fire resistant material and the metal melt, passing the closing element through the melt toward the bottom of the vessel, compressing the compressible material against the bottom of the vessel to form a seal between the outside of the closing element and the tap hole below the closing element, and moving a cut off device over the outside of the tap hole, thereby allowing the tap hole to be filled with a pourable refractory compound via the tubular closing element. A device for performing the process for closing a tap hole includes a tubular closing device with a groove at an end bottom facing the bottom of the metallurgical vessel.

Abstract: The invention relates to a tap-hole drilling machine comprising a separate guiding means for a tap-hole drill and a driving means to move this guiding means between a working position and a rest position. In the working position, the guiding means forms a guide for a tap-hole drill. In the rest position, the guiding means is in a protected position behind a protective shield. The guiding means and driving means are combined in compact cassette-form guiding and protection unit which is removably suspended at the front end of the mount. The protective shield is suspended on the front face of this cassette-form guiding and protection unit and has a through hole for a tap-hole drill.

Abstract: A nozzle or tube which is useful for pouring molten metal, especially aluminum killed molten steel. The nozzle is formed from a blend of doloma and graphite which is bonded together in a carbonized matrix. Nozzles or tubes made in accordance with this invention have enhanced thermal shock resistance. Furthermore, the nozzles or tubes of this invention resist the formation of aluminum oxide therein when they are used for pouring molten aluminum killed steel. Consequently, these tubes or nozzles can be used in a continuous casting process for a long period of time without having to periodically stop the procedure and change the tubes as they become blocked with aluminum oxide. As a result of the thermal shock resistance, the usual preheating step prior to contacting the nozzle with the molten metal is greatly reduced.

Abstract: A tundish of improved flow characteristics for molten metal has an outlet in its base. The outlet is spaced longitudinally of the tundish from a pour zone. The pour zone is positioned to receive a stream of molten steel from a ladle. An impact pad is provided on the floor of the tundish in the pour zone, the impact pad comprising a base having an impact surface, an upwardly extending side wall along the periphery of the base, the side wall having an inner surface with an undercut portion to face the incoming steel stream, and the undercut portion having a surface shape to receive and reverse the direction of flow of the incoming stream. A dam is positioned between the impact pad and the outlet. The dam has one or more holes to allow through-passage of a proportion of the steel, and the dam extends upwardly from the tundish floor about 40-60% of the height of the uppermost level of steel in the tundish.

Abstract: A metallurgical vessel having a sloping bottom surface which includes a tapered upper surface terminating at a vertical surface, wherein the vertical surface terminates at a lower tapered surface for forming a pocket block reservoir such that the pocket block reservoir has a volume of less than or equal to about five percent of the total volume of the metallurgical vessel is disclosed. This pocket block reservoir provides an area for the accumulation of residue metal and slag when the metallurgical vessel is discharged, therefore resulting in a significant increase in the quantity of usable pure metal discharged from the metallurgical vessel and thus contributing to improved volumetric efficiency of the vessel. A method for improving the yield efficiency in the production of metal employing this vessel is also provided.

Abstract: A chamber for receiving a downward flow of liquid metal includes a generally horizontal base having a generally planar impact surface. A first faceted sidewall having a plurality of facets formed therein, generally extends upwardly from and encompasses the planar surface to define an interior space. The interior space has an upper opening for receiving the downward flow of liquid metal. A second wall extends inwardly and upwardly from the first faceted wall toward the upper opening. A plurality of buttresses are spaced along the first faceted wall. Each of the buttresses extends between the impact surface and the second faceted wall. The buttresses form a plurality of discrete pockets including at least one facet. The pockets are defined by the buttresses, the impact surface, the first faceted wall and the second wall. The buttresses laterally deflect and divide the radial outward flow into a plurality of discrete flow patterns associated with the plurality of pockets.

Abstract: In a petroleum coking drum, a drill stem guide latches internally to a structure adjacent the drum opening, rather than externally to a flange about the drum opening. In preferred embodiments, the latching mechanism is spring loaded, and operated automatically as a function of raising and lowering the guide.

Abstract: By a method that may be used for transferring molten metal by using pressurized gas, molten metal in a metal furnace is automatically sucked into a molten metal chamber installed within the metal furnace through a fluid suction pipe by a balanced pressure inside the chamber. Then, when the molten metal sucked into the chamber is transferred to a specified position through a fluid feed pipe by applying a pressurized gas from an upper part of the chamber, the flow rate of the molten metal at the junction part between the fluid suction pipe and feed pipe or at the opposed part of an open end of the fluid suction pipe against that of the fluid feed pipe is accelerated, creating a higher flow rate at other parts of the fluid feed pipe. A molten metal transfer apparatus includes a molten metal chamber installed in a metal furnace and having a tightly closed upper part.

Abstract: A cooled elongated, preferably threaded and, tapered, metallurgical taphole plug and a method for using it are described. The plug is inserted into a taphole to cause a plug of molten material to freeze in the taphole such that molten material flow within the taphole is stopped. In one embodiment, the plug is comprised of an externally threaded, elongated member having a first end and a second end with a taper extending at least partially therebetween. The first, narrower end, which is inserted into the taphole, is cooled by a fluid flowing through an internal passage extending at least partially between the first and second ends. As the first end is cooled, the molten material adjacent the first end freezes around the tip of the first end, effectively plugging the taphole. The device is removed by discontinuing fluid flow and applying a rotational moment about the second end such that the threaded, tapered device backsout of the taphole.

Abstract: Slag from a pool of molten slag floating on molten metal in a plasma arc treatment chamber is removed by providing a slag container located inside the chamber which has a slag intake pipe extending from a bottom of the container downwardly into the slag pool. A vacuum line is connected to the top of the container and a vacuum source. When a vacuum is applied to the inside of the container, the pressure prevailing in the chamber pushes the slag from the pool through the intake pipe into the container. When the container becomes filled with molten slag, the latter enters a section of the line communicating the top of the container with the vacuum source. As the slag enters the pipe section, it is cooled and solidified to prevent further slag flow into or gas (air) flow through the vacuum line so that the container can be lifted out of the chamber while the slag in the container is still in its molten state without causing slag spillage.

Abstract: The present invention is concerned with an apparatus for supply of molten metal including a holding furnace pivotable about an axis having a metal chamber for holding molten metal, an outlet for supplying molten metal from said chamber and an inlet well communicating with said metal chamber, said inlet well being positioned on or adjacent the pivot axis of the holding furnace and displaced along the pivot axis from said outlet, a charging means for intermittently supplying a controlled flow of molten metal to the inlet well of the holding furnace, and a control means for varying the degree of pivot of the holding furnace to maintain a predetermined supply of molten metal. Also claimed as a holding furnace for the supply of molten metal, and a method for supplying molten metal using such apparatus.

Abstract: A heating element comprising:a body having a heating section;heating means inserted in or adjacent to said body, said means capable of generating heat, having a heat flux Q.sub.1 at a temperature T.sub.1 ; andheat transfer and concentration means capable of transferring said heat from said heating means to said heating section and concentrating said heat in said section such that said section has a heat flux Q.sub.2 at a temperature of T.sub.2, where Q.sub.2 is greater than Q.sub.1 and where T.sub.2 is equal to or less than T.sub.1.

Abstract: A flow control device for the outlet of a molten metal handling vessel is provided for use towards the end of the pouring of molten metal through the outlet. The flow control device has a head portion and a tail portion with flow channels defined between the head and tail portions to reduce vortex effects in the molten metal, the tail portion being contoured to fit into a correspondingly contoured entrance to the outlet with the flow channels leading into the outlet and the device being attached to a refractory positioning device so that it can be fitted into the outlet during flow of the molten metal through the outlet. The head includes a baffle plate covering the outlet.

Abstract: A cover is provided for a launder, or an equivalent open-topped vessel for containing molten metal, the cover including a heat-insulative layer spanning the open top of the vessel, with a spacer arrangement to maintain a gap of uniform width between the heat-insulative layer and the open-top. A housing defines an evacuation plenum, and connections are made to allow an exhaust device to remove gaseous materials from the plenum. Adjacent the gap is an air-guide arrangement which directs outside air into the evacuation chamber along a path which is intercepted by any gaseous materials exiting through the gap, whereby such gaseous materials are entrained into the evacuation chamber.

Abstract: A flow control device for the outlet nozzle for a molten metal handling vessel, such as a ladle, includes a plug that fits in the outlet nozzle to define a gap between the plug and a closure for the nozzle. The plug has a plurality of apertures which are closed by steel plates, or other material, that melts under the influence of the molten metal in the vessel. When molten metal is placed into the vessel and the closure for the outlet is opened, the molten metal flows into the apertures, melting the meltable material in the apertures, and out the outlet. Using a device and method described allows the amount of molten metal in a ladle to be reduced to about 0.5%, and a greater than 99% free opening rate can be provided.

Abstract: Charging device for supplying liquid metal to an electric furnace with a shaft 15, the device consisting of a balcony 19 extending the shaft 15 of the furnace 10 laterally and communicating with the hearth of the furnace 10.

Abstract: An apparatus and method for tapping a reactor containing a molten fluid are disclosed. A conduit extending from the reactor is heated to a temperature which causes fluid extracted from the reactor to remain molten while in the conduit. Molten fluid is removed from the reactor by reducing the pressure in a receiving vessel attached to the conduit. As the pressure is reduced in the receiving vessel, molten fluid flows out of the reactor and into and through the conduit, discharging into the receiving vessel. The flow of molten fluid can be terminated by repressurizing the receiving vessel, thereby directing molten fluid in the conduit back into the reactor.

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: In tapping method in which molten iron (16) and molten slag (18) are discharged from a blast furnace, a conducting pipe (30) is connected to the external side of a molten iron taphole (12), and an electromagnetic energy supply body (32) is disposed around the outer periphery of the conducting pipe (30), whereby a turning motion or a magnetic pressure due to an electromagnetic repulsive force to the molten iron flowing in the conducting pipe (30) for separating the molten iron (16) from the molten slag (18) thus controlling the discharge rates thereof. With this tapping method, it becomes possible to keep substantially constant the discharged amounts of molten iron and molten slag from the blast furnace during a period from the starting to the completion of the tapping and significantly reduce the number of drilling/blocking upon tapping, and hence to stabilize quality of products and save the tapping work.

Abstract: A spout-filling composition has from about 50% to about 70% by weight magnesium-aluminate spinel aggregate, from about 50% to about 30% by weight quartz sand, and lampblack in an additional amount of from about 0.25% to about 5.00% by weight of the magnesium-aluminate spinel aggregate and quartz sand admixture.

Abstract: An apparatus and a process are provided for transferring molten metal. The disclosed apparatus includes a vessel having a cylindrical wall, a closed end, and an open end. An opening is provided in the cylindrical wall for pouring molten metal into the vessel. A spout is formed over the open end of the cylindrical wall and provides an orifice from which the molten metal can be discharged from the vessel. The cylindrical wall, the closed end, and the spout define an enclosure for holding the molten metal.The disclosed process employs a vessel as described above for holding molten metal. The vessel is positioned adjacent to a first processing station containing molten metal from which the molten metal is cast into the vessel. The molten metal is then transported directly to a second processing station in the vessel and discharged from the vessel directly into the second processing station for further processing.

Abstract: A method is disclosed for the semi-continuous melting of ceramic material by means of inductive melting in high-frequency and medium-frequency induction melting furnaces whose melting coil surrounds a sintering crust crucible and contains a run-out channel. In the method, melt is periodically run out and material to be melted is supplied to the crucible so as to replace the material removed preferably so as to maintain a constant level. An intensively cooled channel is used as a run-out device. For the melt broaching, the melt nose is grasped from below by way of an automatically controllable broaching lance of a broaching device and raised. The broaching lance is then advanced between the bottom of the channel and the solidified melt until the sintering crust is pierced. The method permits a reliable and economic management of the process and the maintenance of the quality of the melted products.

Abstract: An electric arc furnace or convertor is provided with a taphole collector nozzle which is provided, for at least a portion of its length, with an offset bore enlargement. The furnace may be a tilting arc furnace, and may be provided with a sliding gate taphole valve having a collector nozzle with an offset bore enlargement attached to the sliding gate.

Abstract: A method and apparatus are provided for controlling slag in a trough of a tilting furnace or in a free-standing tilting vessel. On a tilting furnace, the apparatus is mounted on a trough extending from the furnace tap hole and has a reservoir for receiving flow of molten metal and slag from the trough. The reservoir has a slag opening. One of its walls functions as a dam with a bottom opening. A passage extends from the bottom opening along a weir which terminates at an elevation above the bottom opening but below the slag opening. The molten metal flows over the weir and out of the device. The slag is retained in the reservoir and is discharged from the reservoir through the slag opening. In the free-standing tilting vessel, there is a reservoir, slag opening, dam portion, bottom opening, passage and weir, of a substantially similar design as that of the apparatus attached to a trough of a tilting furnace.

Abstract: Apparatus for delivering molten metal such as lead to a receiver comprising a variable speed pump and a delivery pipe leading from the pump. The delivery pipe has an upwardly extending portion which leads to a discharge orifice from which molten metal may be discharged. A variable speed motor drives the pump. A controller causes the motor to drive the pump selectively at a first speed sufficient to raise molten metal and maintain it at a predetermined level in the upwardly extending portion of the delivery pump and at a second speed sufficient to force molten metal in the delivery pipe from the discharge orifice.

Abstract: A machine is provided for piercing a taphole for a shaft furnace for applying the piercing rod method. The machine comprises a mounting (20), a drive means (42, 44), a clamp (34) for coupling the drive means to the rod (26) during its extraction. It is characterised by a push-member (34) transmitting the said thrust force to the rear end of the rod (26) during the insertion of the rod (26) into the taphole clay and by intermediate guides (55i) surrounding the rod (26) at several places during the insertion of the rod (26) into the taphole clay. The said guides (55i) being successively placed in a position in which they do not hinder the advance of the said push-member (34, 78) on the mounting (20).

Abstract: A method and apparatus are provided for separating molten metal and slag from a rotating furnace. The apparatus includes a vessel having a reservoir which is positioned to receive a free-falling flow of molten metal and slag as it exits a tap hole in the furnace. The reservoir has a predetermined flow path therethrough, a molten metal outlet, a slag opening and a drain hole. The flow path includes a first portion having an open top for receiving the flow of molten metal and slag. The first portion is configured to eliminate turbulence caused by the free-falling flow of molten metal and slag into the reservoir and to permit separation of the molten metal from the slag wherein the slag floats on top of the molten metal. The molten metal is collected from the metal outlet for further processing and the slag is collected for disposal.

Abstract: A tilting device for a direct current arc furnace and a process are disclosed for completely emptying the furnace while the furnace is operated with a continuous scrap supply through a lateral opening in the furnace vessel and removal bottoms. The scrap chute should remain in the opening of the furnace during the loading, melting, deslagging and tapping operations; it should be swiveled away only during the emptying of the furnace. The disclosed tilting device has a cam on the rolling cradle, so that the rolling mid-point remains at the zero position in a tilting range from .+-.5.degree. to .+-.15.degree., and when the furnace is completely emptied it moves to another position in a parallel direction to the bottom tapping opening. The position of the bottom tap opening changes only insignificantly in order to protect the parts of the bottom electrode located outside the vessel of the furnace from heat radiated by steel in the casting ladle.

Abstract: Molten (M) is poured into a receiver (8,28) designed to reduce fume and then out into an open area (P) via an outlet (9,29) designed to cause the metal (M) to flow in a laminar flow. A hood (11) may be present above the receiver (8,28).

Abstract: This method comprises injecting a first primary plugging mass (4), mixed with a binder, having given composition and physico-chemical properties, and allowing this primary mass to thermically solidify; after a baking of this primary mass, drilling a hole (8) of a given length and thereby achieving a degassing, and injecting in this hole a second plugging mass, termed secondary mass, having suitable composition and physico-chemical properties which is mixed with a binder and is more fluid than the primary mass and has a hardening speed lower than the hardening speed of the primary mass, so that the secondary mass can diffuse into cracks in the primary mass before solidifying. The secondary mass reinforces the zones of the primary mass which have been rendered fragile by microcracking, and thereby again provides a suitable length of the tapping hole.

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: A method and apparatus for inserting a nozzle into the discharge bore of a steelmaking vessel including a carriage and a clamp means for demountably attaching the nozzle to the carriage. The apparatus further includes means to move the carriage toward or away from the steelmaking vessel while at the same time rotating the nozzle about its longitudinal axis as it is pressed into the discharge bore.

Abstract: A method is provided for facilitating the introduction of a piercing rod into a taphole previously closed by a taphole clay. The rod is gripped by a clamp which imparts to the rod a powerful axial force and an oscillatory movement about its longitudinal axis.

Abstract: A method and product improve the positioning of loose anti-skulling material in the outlet nozzle zone of a metallurgical pouring vessel. The formation of skull in the outlet nozzle zone of a metallurgical pouring vessel is inhibited by positioning in the outlet nozzle zone an elongated container containing loose anti-skulling material, the container being formed of an intumescent material so that when heated it expands to fill the gap between itself and the walls of the nozzle and releases the anti-skulling material.

Abstract: A machine for piercing a taphole for a shaft furnace in the so called "lost rod" method is presented. After the taphole is blocked with a taphole clay but before the taphole clay has fully hardened, a piercing rod is driven into the taphole clay by this machine so that at the desired time the taphole can be opened by extracting the piercing rod by this same machine. This piercing machine comprises a mounting, a first carriage which can be displaced along the mounting, a drive mechanism for this first carriage, guide mechanism to guide the piercing rod and finger mechanism capable of exerting axial thrust upon the piercing rod. The guide means define a guide channel for the piercing rod, which guide mechanism also has a longitudinal opening that gives access to the inside of the guide mechanism, the guide channel being perpendicular to the axis of the longitudinal opening.

Abstract: A machine and method is provided for piercing a taphole for a shaft furnace. The machine comprises a mounting, with a support installed on the mounting so as to support a rod at the front of the mounting, a rear support which can move on the mounting and is provided with means for being coupled to the rear end of the rod and a clamp mounted in a sliding manner on the mounting and designed to grip the rod at any place between the front support and the rear support. A powerful rotary motor installed at the rear of the mounting drives an endless chain installed axially in the mounting. A clamp attached to the endless chain moves during the insertion of the rod into the taphole clay by reversal of the direction of rotation of the motor in a to-and-fro motion between a position (B) at the front of the mounting and a position (A) which is located at a distance L from the position (B).

Abstract: A machine for boring a tap hole of a shaft furnace is presented for use in conjunction with a lost-rod process. In this process, a metal rod is driven into a botting mass, before it has completely hardened, and is removed later for opening a tap hole. Driving-in of the rod is performed with the aid of a to-and-fro movement of a clamp which can move over a mount through action of a first jack. Removal is performed with the aid of a continuous reverse movement of the clamp through the action of the first jack and of a powerful drive means, for example a second jack, driving the first jack towards the rear of the mount.

Abstract: A bottom pour casting apparatus (100) includes a vessel (114) having a bottom nozzle (118). A stopper rod (112) is coupled to a programmable controller (250) by linkage mechanism (250) for controlling the movement of the stopper rod (112) according to a pouring schedule. An LDT position sensor (216) is coupled to the stopper rod (112) by a cable (238) and also electronically to the controller (250) for sensing the actual position of the stopper rod during a pouring cycle and conveying this information directly to the controller (250) thereby bypassing any backlash present in the linkage mechanism (116) to enable precise control of the stopper rod movement. A method includes rezeroing the position sensor (116) at the beginning of each pouring cycle to account for slag build-up on the nozzle (118).

Abstract: A tapping pipe is provided for a melt vessel having a predetermined melt maximum bath level X.sub.m. The tapping pipe defines a flow passage therethrough which has a discharge zone having flow cross-sections approximately the same as the cross-sections of the flow profile of a free flowing stream of the melt from a melt bath level X.sub.0 between 30% and 70% of the maximum melt bath level X.sub.m. The discharge zone can be provided by a brick defining the discharge zone, together with additional bricks defining a feed zone and a transition zone between the feed zone and the discharge zone. In making a number of replacements of the tapping pipe in a converter, the length of the brick defining the transition zone can be gradually reduced so as to compensate for the wear of the converter lining.

Abstract: A machine is provided for piercing a taphole for a shaft furnace for applying the piercing rod method. The machine comprises a mounting, with a support for supporting the rod at the front of the mounting, a sliding support for supporting the rod at the rear of the mounting and a clamp, mounted in a sliding manner on the mounting and designed for gripping the rod at any place between the front support and the rear support. A travel multiplier is connected between a jack and the clamp so that the clamp may be moved. Means for controlling the jack make it possible to move the clamp in a to-and-fro motion between a position (B) at the front of the mounting and a position (A) which is located at a distance L from the position (B).

Abstract: A process and apparatus carries out the direct removal of slag floating on the molten metal within a metallurgical furnace via vacuum suction-tube which is inserted from above through a furnace discharge opening. The tube discharge is connected into an evacuated external slag-cooling chamber, within which the slag stream exiting the suction-tube is granulated by impinging water jets. The water and entrained slag granules descend by gravity through a communicating water-column vacuum-leg, terminating in an atmosphere-exposed pool, within which the granules are collected on a conveyor which dewaters the granules while carrying the slag out of the pool to an external pile or bin. The invention is capable of realizing slow slag discharge at controlled rates over long time periods, as well as in conjunction with the simultaneous and continuous metal withdrawal by a somewhat analagous metal siphon tube into an evacuated metal withdrawal chamber for casting.

Abstract: A sliding gate valve having a frame, a sliding carrier within the frame, means for securing the carrier in reciprocating relationship to the frame, a stationary plate secured at the upper portion of the valve, and a slide gate secured at the lower portion of the valve is disclosed. In one embodiment a spring plate is provided with beam springs cantileverly mounted on its under side having their end portions oriented in surrounding relationship to the teeming opening of the valve, and in addition, providing a cluster of such springs at the shut-off portion of the slide gate which underlies the teeming opening to the vessel in the shut-off position. As to the spring plate, the springs extend downwardly to engage a spring pressure raceway ring formed in the interior portion of the carrier throughout its length and width and partially surrounding the teeming opening of the valve. In addition, a spider-like cluster of springs is provided underneath the shut-off portion to load it when in the shut-off position.

Abstract: A water-cooled plasma torch specially designed to drill into a refractory material is used in a method for opening a tap hole closed by a plug in a wall of a furnace. This method which is particularly well adapted for robotization, includes the step of melting and breaking up the plug closing the tap hole by means of a jet of swirling gas of high speed and high temperature, generated by the plasma torch. The main advantage of this method is that the stream of plasma gas leaving the torch has a well defined outline ensuring precise and reproducible tapping of the plug and, as a result, efficient closing of the tap hole with a new plug after the furnace has been emptied.

Abstract: A method is provided for botting a tap hole of a shaft furnace using a botting gun fitted with a first hydraulic actuating cylinder holding the botting gun in bearing contact against the wall of the furnace, while a second actuating cylinder actuates a piston which injects the botting mass into the tap hole. In order to limit the contact pressures between the tip of the botting gun and the wall of the furnace, the supply pressure P.sub.1 of the first actuating cylinder is modulated as a function of the supply pressure P.sub.2 of the second actuating cylinder.

Abstract: A method and apparatus are provided for controlling slag in a tilting furnace. The apparatus is mounted on a trough extending from the furnace tap hole and has a reservoir for receiving the flow from the trough. The reservoir has a slag opening and a bottom opening. A passage extends from the bottom opening along a weir which terminates at an elevation above the bottom opening but below the slag opening. The molten metal flows over the weir and out of the device, and the slag is retained in the reservoir and is discharged from the reservoir through the slag opening.

Abstract: A plant for the production of molten metals, includes a melting vessel and a metallurgical vessel receiving the melt from the melting vessel for aftertreating the melt and closed by a lid. The melting vessel has a tap opening for the melt provided on the bottom level of the melting vessel and located on the periphery of the melting vessel. The tap opening is positioned above a pour-in opening of the metallurgical vessel. In order to ensure a continuous melting procedure, the pour-in opening of the metallurgical vessel following the melting vessel is provided above a melt guiding chute arranged within the metallurgical vessel.