摘要:
An apparatus for dispensing fusible material onto a surface, wherein the fusible material is in molten form, is provided. The apparatus comprises a dispensing assembly comprising a seal structure. The seal structure controls dispensing of the fusible material. One or more gas injectors are coupled to the dispensing assembly. Each of the one or more gas injectors is adapted to inject at least one gas to the dispensing assembly for controlling a gas environment surrounding at least a portion of the seal structure. An oxidation rate of the fusible material is controlled as a function of at least one characteristic of the at least one gas.
摘要:
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. The resulting inert gas flow shields the seat portion of the bore from ambient oxygen, thereby preventing the accumulation of alumina deposits on the seat portion that can interfere with the ability of the stopper rod to control the flow of molten metal.
摘要:
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. The gas-release device communicates with the channel and releases gas into the channel into the molten metal stream.
摘要:
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. The thermal resistance of the steel pipe substantially reduces the temperature that the coupling is exposed to. The invention also encompasses a method for facilitating the assembly and maintenance of the slide gate valve by the use of the unitized nozzle and top plate in lieu of the in situ mounting of such a nozzle on a top plate already installed in such a valve.
摘要:
An insert member including a plurality of strand members having first and second ends and being oriented in a relative spatial relationship representative of a predetermined path, first end portions for mounting the first ends of the strand members and second end portions for mounting the second ends of the strand members, wherein the first and second means are separated by a predetermined distance to provide the predetermined spatial relationship of the strand members. Also, a combination for making a ceramic gas distribution device which includes this insert member and at least one ceramic in an unfired or green state cast partially therearound. The invention also provides methods for making a ceramic gas distribution device by placing a plurality of strand members in a predetermined orientation representative of a plurality of gas passages; casting a first ceramic about the strand members; allowing the cast ceramic to set to an unfired or green state; and firing the ceramic material to a final state while vaporizing the strand material therein to thus provide gas passages therein. The invention also relates to the ceramic gas distribution devices formed by these methods.
摘要:
An immersion nozzle (2) for metallurgical recipients, in particular for a reservoir arranged upstream of a continuous casting ingot mould, has an interchangeable discharge pipe (2) which can be attached in a leakproof manner on or in a perforated brick (1). To improve the flow conditions and hence the efficiency of the casting, the inlet side of the nozzle comprises an upper elongated section (12) in the form of a tubular shaft (11) which expands conically downward to a given plane and which is narrow in a plane perpendicular to the given plane. A second elongate section (13) ends in an elongated transverse flow section of given dimensions.
摘要:
An assembly includes a discharge member of a metallurgical vessel and a pipe member connected to the discharge member at mutual surfaces thereof defining a seat therebetween. An annular recess is formed in the region of such seat, a seal seals such seat, and gas is supplied to the annular recess. The seal is in the form of a pair of compressible sealing rings positioned between the mutual surfaces of the two members on opposite sides of the annular recess. A pressure indicator is connected to a gas supply line supplying gas to the annular recess to provide an indication of the pressure of gas prevailing in the annular recess, and particularly of changes of such pressure.
摘要:
A nozzle for discharging molten metal from a vessel includes a porous inner sleeve surrounded by an impervious outer sleeve. The outer sleeve is cast in-situ around the inner sleeve, and is bonded in-situ to the outer surface of the inner sleeve in bonding areas adjacent its opposite ends. A gas chamber is defined between the inner and outer sleeves for receiving pressurized gas which passes through the inner sleeve to inhibit clogging and deterioration of the inner sleeve by molten metal and impurities. The gas chamber is formed by placing a heat fluidizable material around a portion of the inner sleeve before the outer sleeve is cast thereon. After casting of the outer sleeve, the assembly is heated to a temperature for fluidizing the fluidizable material which then escapes through the porous sleeve to leave a hollow gas chamber.
摘要:
A sliding closure unit includes a movable plate movable between open and closed positions to control the discharge of molten metal through an outlet opening of a metallurgical vessel. When the movable plate is in the closed position, a continuous flow of gas is injected from a gas supply system through the area of the movable plate confronting the outlet opening into the outlet opening. When a predetermined gas back pressure occurs in the gas supply system, indicative of solidification of molten metal in the outlet opening, at least one pressurized gas jet at a pressure of at least 12 bar is injected from a compressed gas supply system into the outlet opening, thereby clearing away any solidified metal from the outlet opening. This makes it possible to ensure that, when the movable plate is moved to the open position, the molten metal will be discharged through the outlet opening at a full flow rate of discharge.
摘要:
An apparatus for mounting a gas washing sink in a centered manner within an opening through a perforated brick in a wall of a metallurgical vessel and for removing the sink from the perforated brick includes a support assembly to be fixedly mounted on the exterior of the wall of the metallurgical vessel adjacent the opening in the perforated brick. A fastening assembly supports the sink and is mounted with respect to the support assembly for movement relative thereto between an operating position, whereat the sink is pressed into the opening through the perforated brick in a centered manner, and a maintenance position, whereat the sink is withdrawn from the opening through the perforated brick. Structures moves the fastening assembly relative to the support assembly to the operating position. A withdrawal apparatus moves the fastening assembly relative to the support assembly from the operating position to the maintenance position.