Abstract: A lance for conducting a pyrometallurgical operation by top submerged lancing (TSL) injection, has inner and outer substantially concentric pipes. The lower end of the inner or at least a next innermost pipe is set at a level relative to the lower end of the outer pipe required for the pyrometallurgical operation. The relative positions of the inner and outer pipes are longitudinally adjustable to enable the length of the mixing chamber to be maintained at a desired setting during a period of use to compensate for the lower end of the outer pipe wearing and burning back.

Abstract: The invention relates to a cooling element for a pyrometallurgical furnace such as for a flash smelting furnace or for a flash converting furnace or for a suspension smelting furnace. The invention relates also to a method for manufacturing a cooling element for a pyrometallurgical furnace such as for a flash smelting furnace or for a flash converting furnace or for a suspension smelting furnace. The cooling element (2) has a fire surface (2) to be in contact with an interior of the metallurgical furnace. The cooling element comprises a base element (4) containing copper and a coating (5) at least partly covering the base element (4). The coating (4) forms the fire surface (2) of the cooling element (1). The coating (5) is at least partly applied by a laser coating process such as laser deposition, and the coating (5) contains a Ni based alloy.

Abstract: A tuyere for an iron making furnace, including a body unit having a blast passage passing through a central axis thereof, wherein the body unit includes: a frusto-conical body having a main body cooling passage; and a protruding part protruding from the body, wherein the tuyere further includes: a cover unit combined with the protruding part and defining a tip body cooling passage between the cover unit and the outer circumferential surface of the protruding part; and an outer unit combined with the cover unit while surrounding the cover unit and defining an outer cooling passage therein. When the outer unit is partially damaged, although the cooling water supply to the damaged part is cut off, the function of the tuyere can be continuously performed both by the remaining part of the outer unit and by the body unit, thereby providing a tuyere having a lengthened life span.

Abstract: An oxygen supplying apparatus of a melting furnace, in which waste contained within the melting furnace is stirred by using an oxygen supplying member of the melting furnace, includes an air cooling member provided in a through hole formed on the melting furnace and mounted on the oxygen supplying member to allow an outside air to enter thereto.

Abstract: A lance for injecting a solid material into a vessel, such as a direct smelting vessel for producing molten iron, has a core tube assembly comprising a passageway for solid material. The core tube assembly has an inlet for receiving solid material at a rear end and an outlet for discharging material at a forward end. The core tube assembly comprises an outer tube of a structural material and an inner tube of a wear resistant material that are bonded together. A method of manufacturing the core tube assembly may include spin casting the outer tube of the structural material; spin casting the inner tube of the wear resistant material onto the inner surface of the outer tube; and metallurgically bonding the tubes together.

Abstract: An injector insert pipe is arranged in the gas channel of a nozzle for injecting oxygen-containing gas into a pig iron production unit, wherein an interspace which surrounds the pipe is present over the entire pipe length between the wall of the gas channel and the pipe outer wall. The pipe extends at least as far as the nozzle end face which contains the mouth of the gas channel. The pipe space is connected to an oxygen-containing gas feed line, and the interspace is connected to a protective gas supply line. In a process, oxygen-containing gas is fed into the pipe space, which after it has flowed through the pipe, enters the production unit at an entry velocity, and the interspace is simultaneously flowed through by a gas which exits into the production unit at an exit velocity, wherein the entry velocity is greater than the exit velocity.

Abstract: A tuyere structure of a melting furnace includes: a tuyere main body which is covered on an outer periphery thereof with a ring member baked in advance, and is disposed in a hole portion provided in a tuyere brick; and a ramming material which fills a periphery of the ring member so as to fix the ring member.

Abstract: An apparatus for injecting particulate and/or gaseous material into a metallurgical vessel for use in a metallurgical process includes a duct to inject the material. The duct includes a duct wall of concentric annular passages for inflow of cooling water from a rear end to a forward end of the duct along a first of the annular passages and for outflow of cooling water from the forward end to the rear end of the duct wall along a second of the annular passages. The concentric annular passages are provided by concentric sleeves that consist of an inner sleeve, an outer sleeve, and an intermediate sleeve. The apparatus also includes a duct tip at a forward end of the duct joining at least the inner and outer sleeves so as to provide a water flow connection between the first and second water flow passages.

Abstract: This invention relates to a gas blowing nozzle for blowing a gas to a molten metal in a furnace, the gas blowing nozzle including: a first nozzle section including a plurality of first narrow metal pipes having open furnace-side tips exposed to an inside of the furnace and being in the state of capable of blowing a gas to the molten metal in the furnace, a first surge tank communicated with the first narrow metal pipes, and a first refractory protecting the first narrow metal pipes and the first surge tank; and a second nozzle section including a plurality of second narrow metal pipes, a second surge tank communicated with the second narrow metal pipes, and a second refractory protecting the second narrow metal pipes and the second surge tank.

Abstract: The present invention relates to an injector for an arc furnace. The injector comprises a head suitable to face into the furnace and a body suitable to support the head. The head and body are manufactured separately from each other, and are fastened by means of removable connection means in order to implement said injector.

Abstract: A novel blaster nozzle used for assisting in the pneumatic removal of cloggings and cakings during the transport of particulate matter through an enclosure housing is set such that it can be removed and replaced from outside the enclosure housing. The blaster nozzle includes a nozzle head having an orifice for the conduction of high-pressure fluid, wherein the nozzle head is composed of a refractory concrete having from about 4-20% by volume metal fibers therein. The blaster nozzle also includes a flange member connected to the nozzle head and a connection tube extends from the flange member for connecting the blaster nozzle to an air cannon.

Abstract: A method and apparatus for accessing a furnace melt are provided. Preferably, the method and apparatus provide for the safe and efficient access to the melt. According to one aspect of the invention used in a steel-making process in an electric arc furnace, a furnace aperture burner/lance provides a flame for heating the melt, a lance device for injecting oxygen into the furnace, or both. To access the melt, the furnace aperture burner/lance is disengaged, access is provided to the melt through the furnace aperture, and the furnace aperture burner/lance is reengaged when the access is concluded.

Abstract: A cooling system comprises serpentine cooling fluid passages cast into a work piece with carefully controlled turning radii and profiles. Individual interdigitated baffles are contoured in the plane of coolant flow to have walls that thicken and then round off at their distal ends. The outside radii at these turns is similarly rounded and controlled such that the coolant flow will not be swirled into eddies.

Abstract: An apparatus for injecting particulate and/or gaseous material into a metallurgical vessel for use in a metallurgical process includes a duct to inject the material. The duct includes a duct wall of concentric annular passages for inflow of cooling water from a rear end to a forward end of the duct along a first of the annular passages and for outflow of cooling water from the forward end to the rear end of the duct wall along a second of the annular passages. The concentric annular passages are provided by concentric sleeves that consist of an inner sleeve, an outer sleeve, and an intermediate sleeve. The apparatus also includes a duct tip at a forward end of the duct joining at least the inner and outer sleeves so as to provide a water flow connection between the first and second water flow passages.

Abstract: A tuyere for an iron making furnace, including a body unit having a blast passage passing through a central axis thereof, wherein the body unit includes: a frusto-conical body having a main body cooling passage; and a protruding part protruding from the body, wherein the tuyere further includes: a cover unit combined with the protruding part and defining a tip body cooling passage between the cover unit and the outer circumferential surface of the protruding part; and an outer unit combined with the cover unit while surrounding the cover unit and defining an outer cooling passage therein. When the outer unit is partially damaged, although the cooling water supply to the damaged part is cut off, the function of the tuyere can be continuously performed both by the remaining part of the outer unit and by the body unit, thereby providing a tuyere having a lengthened life span.

Abstract: A forged copper burner enclosure capable of being mounted within the side wall of a steel melting furnace for the purpose of providing an improved cooling characteristic to a burner lance. The burner enclosure is provided with a central passage adapted to receive a burner lance for injecting oxygen into the batch of molten metal of an electric arc furnace. The forged burner enclosure is positioned such that only a solid forged copper face is on the furnace side when installed. The burner enclosure has an optional through hole which can be used for the purpose of treating the metal melt with particulate supply ranging from slag forming materials to metallurgical materials.

Abstract: The invention relates to a water-containing slip for producing a BN-containing coating on a substrate, which comprises, based on the solids content of the slip, a) 45-90% by weight of BN, b) 3-25% by weight of boehmite nanoparticles, c) 0.5-5% by weight of at least one borate, d) 2-30% by weight of at least one water-insoluble boron compound which is different from the components a) and c), e) 2-30% by weight of an organic compound, where the solids content of the slip is 15-60% by weight.

Abstract: The invention relates to a cooling element to be used in the structure of a pyromettalurgical reactor used in the manufacturing of metals, which cooling element comprises a housing element mainly made of copper, provided with a channel system for the cooling medium circulation, made of pipe that is mainly made of copper; on the outer surface of the pipes forming the channel system, there is arranged a coating that has a lower melting point than the material of the housing element and the pipe. The invention also relates to a method for manufacturing the cooling element.

Abstract: An apparatus for injecting particulate and/or gaseous material into a metallurgical vessel is disclosed. The apparatus includes a duct through which to inject the material, inner and outer water inflow and outflow passages extending through a wall of the duct and an annular duct tip disposed at the forward end of the duct. The duct tip is of annular formation and includes an annular inner end component, an annular outer end component, and an annular central component located between the inner and outer components. The duct tip also includes a plurality of radially extending dividers to divide a space between the outer end component and the central component into discrete radial passages to serve as the internal water flow passages of the tip.

Abstract: A method and apparatus for accessing a furnace melt are provided. Preferably, the method and apparatus provide for the safe and efficient access to the molten metal melt in a furnace. According to one aspect of the invention used in a steel making process in an electric arc furnace, a furnace aperture plug is reciprocated through a furnace aperture, the furnace aperture plug is retracted from the furnace aperture, access is provided to the molten metal melt in the furnace, and the furnace aperture plug is reinserted into the furnace aperture when the access is concluded.

Abstract: A composite sparger for use in elevated temperature and corrosive environments. The composite sparger is formed from a substrate tube with a thermally conductive interlayer on its surfaces exposed to the reactor environment. The thermally conductive interlayer is protected with a corrosion resistant layer. The corrosion resistant layer protects the interlayer from the corrosive environment of the reactor vessel and the interlayer material conducts heat away from the corrosion resistant layer to prevent combustion of the corrosion resistant layer. The interlayer material and corrosion resistant material may be selected so as to provide for sufficient thermal conduction to prevent combustion of the corrosion resistant material.

Abstract: A composite sparger for use in elevated temperature and corrosive environments. The composite sparger is formed from a thermally conductive non-combustible metal substrate. The surfaces of the conductive non-combustible metal exposed to the reactor environment are protected with a corrosion resistant layer. The corrosion resistant layer protects the substrate material from the corrosive environment of the reactor vessel and the substrate material conducts heat away from the corrosion resistant layer to prevent combustion of the corrosion resistant layer. The substrate material and corrosion resistant material may be selected so as to provide for sufficient thermal conduction to prevent combustion of the corrosion resistant material.

Abstract: A novel blaster nozzle (10) used for assisting in the pneumatic removal of cloggings and cakings during the transport of particulate matter through an enclosure housing is set such that it can be removed and replaced from outside the enclosure housing. The blaster nozzle includes a nozzle head (12) having an orifice for the conduction of high-pressure fluid, wherein the nozzle head is composed of a refractory concrete having from about 4-20% by volume metal fibers therein. The blaster nozzle also includes a flange member (14) connected to the nozzle head and a connection tube (18) extends from the flange member for connecting the blaster nozzle to an air cannon.

Abstract: A cooling system comprises serpentine cooling fluid passages cast into a work piece with carefully controlled turning radii and profiles. Individual interdigitated baffles are contoured in the plane of coolant flow to have walls that thicken and then round off at their distal ends. The outside radii at these turns is similarly rounded and controlled such that the coolant flow will not be swirled into eddies.

Abstract: An apparatus for injecting particulate and/or gaseous material into a metallurgical vessel is disclosed. The apparatus includes a duct through which to inject the material, inner and outer water inflow and outflow passages extending through a wall of the duct and an annular duct tip disposed at the forward end of the duct. The duct tip is of annular formation and includes an annular inner end component, an annular outer end component, and an annular central component located between the inner and outer components. The duct tip also includes a plurality of radially extending dividers to divide a space between the outer end component and the central component into discrete radial passages to serve as the internal water flow passages of the tip.

Abstract: A lance for injecting a solid material into a vessel, such as a direct smelting vessel for producing molten iron, is disclosed. The lance has a core tube assembly comprising a passageway for solid material. The core tube assembly has an inlet for receiving solid material at a rear end and an outlet for discharging material at a forward end. The core tube assembly comprises an outer tube of a structural material and an inner tube of a wear resistant material that are bonded together.

Abstract: A forged copper burner enclosure capable of being mounted within the side wall of a steel melting furnace for the purpose of providing an improved cooling characteristic to a burner lance. The burner enclosure is provided with a central passage adapted to receive a burner lance for injecting oxygen into the batch of molten metal of an electric arc furnace. The forged burner enclosure is positioned such that only a solid forged copper face is on the furnace side when installed. The burner enclosure has an optional through hole which can be used for the purpose of treating the metal melt with particulate supply ranging from slag forming materials to metallurgical materials.

Abstract: A smelting apparatus includes a vessel and a solids injection lance extending through an opening in the wall of a vessel barrel into the interior space of the vessel. The lance includes a central core tube through which to pass solid particulate material into the vessel and an annular cooling jacket surrounding the central core tube throughout a substantial part of its length. The lance has a mounting structure including a tubular part extended about the cooling jacket and about twice the diameter of the cooling jacket. The tubular part fits within a tubular lance mounting bracket welded to the shell of the vessel barrel to extend outwardly from the vessel. The lance is held within the mounting bracket by clamping bolts acting between flanges on the tubular part and the tubular bracket.

Abstract: A method and apparatus for accessing a furnace melt are provided. Preferably, the method and apparatus provide for the safe and efficient access to the molten metal melt in a furnace. According to one aspect of the invention used in a steel making process in an electric arc furnace, a furnace aperture plug is reciprocated through a furnace aperture, the furnace aperture plug is retracted from the furnace aperture, access is provided to the molten metal melt in the furnace, and the furnace aperture plug is reinserted into the furnace aperture when the access is concluded.

Abstract: A method and apparatus for testing characteristics of a furnace melt are provided. Preferably, the method and apparatus provide for the safe and efficient testing of metal temperature and composition of molten metal during the melt cycle of the metal. According to one aspect of the invention used in a steel making process in an electric arc furnace, a furnace probe is reciprocated through a furnace probe plug aperture, the furnace probe is retracted from the furnace probe plug aperture, a furnace probe is inserted through the furnace probe plug aperture, the furnace probe is retracted from the aperture, and the furnace probe aperture plug is inserted into the furnace probe plug aperture.

Abstract: The present invention relates to an apparatus for injecting gas into a vessel. The apparatus may include a gas flow duct and a central body within a forward end region of the duct. The central body and the gas flow duct form an annular nozzle for the discharge of gas from the duct. A plurality of flow directing vanes are disposed about the central body to impart swirl to a gas flow through the nozzle. The flow directing vanes have substantially straight leading end portions radiating outwardly from the central body and extending along the duct. The vanes also have substantially helical trailing end portions extending helically about the central body toward the front end of the duct and transition portions joining the leading end portions to the trailing end portions. The transition portions are shaped so as to merge smoothly with both the leading end portions and the trailing end portions and to smoothly and progressively change shape between them.

Abstract: An apparatus for injecting particulate and/or gaseous material into a metallurgical vessel for performing a metallurgical process is disclosed. The apparatus comprises a duct and an annular duct tip at a forward end of the duct. The apparatus also comprises inner and outer cooling water flow passages configured such that out flowing water passing from the duct tip to a rear end of the duct must travel through a longer flow path than inflowing water passing from the rear end of the duct to the duct tip.

Abstract: An apparatus for injecting gas into a vessel includes a gas flow duct which receives hot gas through a gas inlet structure at a rear end of the duct. The forward end of the duct has an annular duct with an internal cooling water passage. Cooling water supply and return passages are formed within the wall of the duct such that water flows to and from a tip through the supply and return passages. The tip includes a hollow shell and a partitioning structure that has a ring and a plurality of circumferential flanges that project outwardly from the ring to the shell to form a series of water flow galleries, each extending circumferentially around the tip and interconnected for flow of cooling water sequentially through the galleries from the water supply passages to the water return passage. The circumferential flanges also serve as buttress supports for the shell.

Abstract: A double chamber single directional spiral tuyere for blast furnaces is disclosed. The tuyere includes a body unit, a spiral unit and a cover unit, with a body chamber having a body nose passage and a body main passage defined in the body unit, and a nose chamber having first, second, third and fourth spiral passages defined in both the spiral unit and the cover unit. The tuyere further includes a tunnel, which is formed in the spiral unit and the cover unit and connects a cooling water inlet to the first spiral passage. Thus, efficient circulation of cooling water and maximum cooling performance can be provided.

Abstract: A tuyere device for introduction of gaseous media under a liquid metal layer comprises a nest block made of refractory material provided with a sleeve incorporated therein, Coaxial metal tubes with at least one central channel and at least one annular channel which are arranged on the side thereof for entering a liquid metal and separately connected to inlets for supplying gaseous media to the metal. The coaxial tubes consist of two sections having different diameters. The first section has a smaller diameter and is used for supplying the gaseous media to the liquid metal. The second section has a larger diameter and is connected to the inlets for supplying gaseous media to the channels of the first section. The second section is also provided with an additional internal tube. The internal tube of the first section is closed on the both ends and filled with a refractory material. The invention provides a possibility to exclude metal break through the operating channels.

Abstract: A metallurgical lance (27a) to extend through an opening in the wall of a smelting vessel barrel (16) and into the interior space of the vessel. Lance (27a) includes a central core tube (31) through which to pass solid particulate material into the vessel and an annular cooling jacket (32) surrounding the central core tube (31) throughout a substantial part of its length. Lance (27a) has a mounting structure (61) comprising an outer annular part (60) extended about cooling jacket (32) and about twice the diameter of the cooling jacket. The outer annular part (60) fits within a tubular lance mounting bracket (62) welded to the shell (16a) of vessel barrel (16) to extend outwardly from the vessel. The lance is held within mounting bracket (62) by clamping bolts acting between flanges (63,65) on the outer annular part (60) and mounting bracket (62).

Abstract: A composite sparger for use in elevated temperature and corrosive environments. The composite sparger is formed from a substrate tube with a thermally conductive interlayer on its surfaces exposed to the reactor environment. The thermally conductive interlayer is protected with a corrosion resistant layer. The corrosion resistant layer protects the interlayer from the corrosive environment of the reactor vessel and the interlayer material conducts heat away from the corrosion resistant layer to prevent combustion of the corrosion resistant layer. The interlayer material and corrosion resistant material may be selected so as to provide for sufficient thermal conduction to prevent combustion of the corrosion resistant material.

Abstract: Smelting apparatus comprises a vessel (11) and a solids injection lance (27a) extending through an opening in the wall of vessel barrel (16) into the interior space of the vessel. Lance (27a) includes a central core tube (31) through which to pass solid particulate material into the vessel and an annular cooling jacket (32) surrounding the central core tube (31) throughout a substantial part of its length. Lance (27a) has a mounting structure (61) comprising a tubular part (60) extended about cooling jacket (32) and about twice the diameter of the cooling jacket. Tubular part (60) fits within a tubular lance mounting bracket (62) welded to the shell (16a) of vessel barrel (16) to extend outwardly from the vessel. The lance is held within mounting bracket (62) by clamping bolts acting between flanges (63,65) on tubular part (60) and tubular bracket (62).

Abstract: An apparatus for injecting particulate and/or gaseous material into a metallurgical vessel for performing a metallurgical process is disclosed. The apparatus comprises a duct and an annular duct tip at a forward end of the duct. The apparatus also comprises inner and outer cooling water flow passages configured such that out flowing water passing from the duct tip to a rear end of the duct must travel through a longer flow path than inflowing water passing from the rear end of the duct to the duct tip.

Abstract: A tuyere assembly for directing air and one or more fluid hydrocarbons into a cavity in a blast furnace. The tuyere assembly includes a blowpipe portion with a conduit defining a bore through which the air is directed. The tuyere assembly also includes a tuyere with a chamber defined by one or more walls thereof, the chamber being in fluid communication with the cavity of the blast furnace, and the chamber of the tuyere and the bore of the blowpipe portion form an internal cavity of the tuyere assembly. Also, the tuyere assembly includes one or more injector subassemblies having one or more outlet ends, each outlet end being adapted for directing the hydrocarbon into the internal cavity for combustion thereof to provide a flame substantially having a preselected flame configuration.

Abstract: A metallurgical lance for injecting particulate material into a liquid comprises a main gas tube 6 defining an axial main gas passage terminating at its outlet and in a first Laval nozzle 38 downstream of the throat of said nozzle. A shrouding gas passage in the form of a combustion chamber 36 surrounds the main gas tube and terminates in a second Laval nozzle 42. A particulate material transport tube 4 defines a passage for the particulate material to be introduced into the first Laval nozzle 38 downstream of its throat. The first Laval nozzle 38 is provided with a passage 40 for the flow of coolant.

Abstract: A tuyere cooling system which includes a coolant circuit for a body section and nose section. A valve is operable to connect the coolant circuits in series or to disconnect flows to the nose section of the tuyere so that if the nose of the tuyere tears during operation, the flow of coolant to the nose section of the tuyere may be cut off without affecting the overall operation of the blast furnace.

Abstract: A check valve assembly for the forced gas cooling system of a vacuum heat treating furnace is disclosed. The check valve assembly includes a check valve for installation on the exterior of a hot zone wall in a vacuum heat treating furnace. The check valve includes a valve body forming an inlet, an outlet, and a channel extending longitudinally through the valve body. The valve body has an inner wall that forms a recess near the inlet. The channel contains a flap pivotally supported on a shaft that extends through the recess. The flap pivots in and out of the channel to permit a cooling gas to flow through the valve body in one direction while substantially preventing the flow of gas through the valve body in the opposite direction. The flap is operable between a closed position in which the flap extends into the channel to obstruct the channel, and an open position in which the flap is pivoted out of the channel and into the recess.

Abstract: A furnace for heat treating of metal parts includes a hot zone enclosure defining a hot zone therein. The hot zone enclosure has a side wall, a first end wall, and a second end wall. The side wall has slots formed therethrough and along the length thereof. The heat treating furnace also includes a system for injecting a cooling gas into the hot zone through the hot zone enclosure. The heat treating furnace further includes a damper arrangement for directing the cooling gas over a selected portion or portions of the workpiece load and through one or more of the slots. In one embodiment of the invention, all actuated components in the furnace are located outside of the hot zone to minimize damage to moving parts that are caused by exposure to extreme heat.

Abstract: A blowing lance nozzle (1) having: a central tube (2) supplying stirring gas, an inner tube (5) for intake of a cooling liquid, an outer tube (10) for evacuation of the cooling liquid, a heat exchanging space (13), and an outlet conduit (15) for the stirring gas exiting from each orifice (4) in the front wall (3). The front wall (12) has a central recess (16) which is oriented towards the central orifice (8) and has a recess height/recess base ratio not less than 0.35. The heat exchanging space has a section for allowing passage of the cooling liquid through the space at a speed which is substantially constant, so as to obtain a cooling liquid passage speed, through the space, which is more or less constant.

Abstract: A convection heating system includes a hot zone enclosure defining a hot zone and a plurality of gas injection nozzles for injecting a cooling gas into the heat treatment zone of furnace. Each gas injection nozzle may include a flap disposed and pivotally supported therein for substantially preventing the escape of heat from the hot zone during a heating cycle, but for permitting the injection of the cooling gas into the furnace hot zone during a cooling cycle. A gas exit port may be provided and may include a flap pivotally mounted therein for impeding the unforced outward flow of a gas from the heat treatment zone during a heating cycle.

Abstract: An injection lance (26) for injecting hot gas into a vessel includes an elongate gas flow duct (31) which receives hot gas from a gas inlet structure (32) and an elongate central tubular structure (33) which extends within gas flow duct (31) from its rear end to its forward end. Adjacent the forward end of duct (31), central structure (33) carries a series of flow directing vanes (34) for imparting swirl to the hot gas flow exiting the duct. The wall of duct (31) downstream from gas inlet (32) is internally water cooled by flow of water through annular passages (43,44). The cooling water also flows through the interior of a duct tip (36) at the forward end of duct (31). The front end of central structure (33) which carries the swirl vanes (34) is internally water cooled by cooling water supplied forwardly through a central water flow passage (52) from a water inlet (53) at the rear of the lance through to a nose (35) of the central structure.

Abstract: A direct smelting process for producing iron and/or ferroalloys is provided, which involves forming a molten bath in a metallurgical vessel, supplying feed materials, injecting oxygen containing gas, generating upward movement of the molten material from the molten bath, wherein the oxygen-containing gas is injected by three or more lances, and entraining into the jets of oxygen containing gas a volume of top space gas that is 2-6 times the volume of the injected gas.

Abstract: The invention relates to a method for producing a metal melt in a metallurgical vessel, in particular an iron or steel melt, feed substances which contain metals and/or metal oxides, being charged in solid and, if appropriate, molten form into the metallurgical vessel, the main part of the energy necessary for the melting and, if appropriate, finish-reduction of the feed substances being applied electrically and/or by the combustion and/or gasification of carbon-containing materials. The invention relates, further, to multi-functional lances for use in a method according to the invention.

Abstract: A nozzle for injecting a cooling gas in a vacuum heat treating furnace is described. The cooling gas injection nozzle according to the present invention has a forward portion with a first central opening formed therethrough. The cooling gas injection nozzle also has a rear portion with a second central opening formed therethrough. A flap is disposed in and pivotably supported in the first central opening. The flap operates to substantially prevent the escape of heat from the hot zone during a heating cycle, but permits the injection of the cooling gas into the furnace hot zone during a cooling cycle. The cooling gas injection nozzle is supported from the hot zone wall by any appropriate means. A vacuum heat treating furnace and a hot zone therefor incorporating the cooling gas injection nozzle are also described.