Abstract: A wall electrode includes a metal bar adapted to extend through the wall of the furnace, a water-cooled sleeve composed of a material which is a good conductor of heat and electricity, an end member composed of a material which is a good conductor of heat and electricity, and an annular member such as a ring composed of a metal which is heavy and has a low melting point surrounding the bar so that the heavy metal in the liquid state spreads in the space between the bar and the sleeve when the annular member is made to melt during use of the electrode.

Abstract: The electric connection device comprises an electrode (5), a sleeve (19) mounted around a projecting end part (8) of the electrode (5), and an arrangement for cooling the sleeve (19) with a cooling fluid comprising at least one system (20, 20') of nozzles (21) spraying cooling fluid onto the outer surface of the sleeve (19).

Abstract: This guniting nozzle end piece for projecting a refractory powder through a flame, the nozzle being connected to a combustive gas, fuel gas and refractory powder feed, one of the gases being the gas carrying the powder in the end-piece, is characterized in that, generally cylindrical in shape, it comprises a plurality of individual tubes (9) disposed in at least one ring (9a,9b) of tubes coaxial with the end-piece (1), opening on the one side at the level of the nose (11) of the end-piece and connected on the other side to the refractory powder and carrier gas feed (20), the plurality of tubes (9) being disposed between two coaxial substantially cylindrical walls respectively internal (12) and external (13), the gaps (24) between the tubes and between the tubes and the cylindrical walls forming a passage space opening on the one side at the level of the nose (11) of the end-piece and further connected to the non carrier gas feed (18).

Abstract: In a process for forming the bottom of a metallurgical container, especially the bottom of a converter for refining pig iron, of the type which comprises a metallic base, at least one layer of refractory material superimposed on the metallic base, a first layer of refractory bricks superimposed on the layer of refractory material, and a second layer of refractory bricks on said first layer, the steps of placing, spaced from each other, on said first layer a plurality of refractory elements permeable to gas and each enclosed in a metal casing open at the top, circumferentially surrounding the metal casing of each of the elements with bricks of a material which expands during rise of the temperature and thereafter completing the second layer with refractory bricks.

Abstract: A process of pneumatic stirring of a bath of molten metal according to which a stirring fluid is injected through permeable refractory elements arranged at the bottom of a crucible containing the bath, in which the used stirring fluid is, at least temporarily, an organic liquid such as hydrocarbon.The process is advantageously used on a bath of molten pig iron during refining of the same by oxygen, and in which the organic liquid is replaced immediately after decarburization of the bath by an inert gas such as argon or nitrogen.The process thus permits an efficient stirring of the bath of molten metal without the risk of polluting the metal either by hydrogen or nitrogen.

Abstract: A process for periodically and pneumatically stirring a bath of molten metal, wherein during the periods in which no stirring effect is required a fluid in gaseous state is injected through injection devices below the surface of the bath of molten metal in an amount sufficient to prevent blockage of the devices, whereas during the periods in which a stirring effect is required a fluid in liquid state which will vaporize quickly upon contact with the liquid metal is injected to provide an optimum amount of mixing gas with a minimum of injection devices.The process is advantageously used in converters for pneumatically converting pig iron into steel and in which oxygen is blown from above onto the bath of molten metal.

Abstract: Process of refining of a metal bath in a crucible with oxygen blast at the top and crucible used.The invention consists essentially of providing in the bottom (15) of the crucible agitating gas injectors (15) located at least in a peripheral circular ring situated in immediate proximity to the refractory side wall. The injectors are preferably concentrated opposite the journals. Secondary injectors are, also preferably, provided in the bottom zone, intermediate between the ring and the center of the crucible.The invention makes it possible, in relation to the prior injection practice, to reduce the rate of dissolution of the agitating gas in the molten metal and then makes it possible to use a low-cost agitating gas, such as nitrogen, without risk of excessive nitridation of the bath.

Abstract: A device for blowing gas under pressure into a bath of liquid metal comprises a mass of refractory material which is porous at least at an inner portion thereof and placed into a metallic container constituted by an outer metallic envelope closed at one of the ends thereof by a bottom member through a central portion of which a conduit extends for feeding a gas under pressure to the porous inner portion of the mass. A deflector is provided fluid-tightly connected to the bottom inwardly of the envelope in which the wall of the deflector extends parallel to that of the envelope but short of the length of the latter. This permits, on the one hand, to avoid penetration of liquid metal between the envelope and the mass of refractory material to a point where it would block the gas feeding conduit and, on the other hand, to canalize the gas through the porous portion of the mass. The present invention relates likewise to a method of making the above device.

Abstract: The refractory piece permeable to gases according to the invention is designed to be incorporated in the inner refractory lining of a metallurgical container so that one of its surfaces will be in contact with the molten metal bath in said container, the opposite surface being equipped with means for introducing a gas under pressure.This piece, whose shape is generally hexahedral, consists essentially of a mass of nonporous refractory material that has a number of local discontinuities 8 extending throughout the piece along its height h between the surface in contact with the molten metal and the opposite surface. In an advantageous method of embodiment, the local discontinuities 8 are obtained by an assembly 1, in a metal casing, of nonporous refractory elements 2, in the form of plates and which are placed side by side along their large lateral surfaces, without any material gaskets or seals between them.The piece according to the invention is easy to make.

Abstract: Stainless steel is produced in a converter with a tuyere defining a central conduit and a peripheral conduit concentrically surrounding the central conduit, by blowing an oxidizing refining gas through the central conduit into a molten metal bath, the refining gas initially consisting of pure oxygen and being subsequently diluted by gaseous argon, and injecting liquid argon into the converter through the peripheral conduit, to refine the molten metal bath until it has attained a desired level of carbon.

Abstract: The refractory piece permeable to gases according to the invention is designed to be incorporated in the inner refractory lining of a metallurgical container so that one of its surfaces will be in contact with the molten metal bath in said container, the opposite surface being equipped with means for introducing a gas under pressure.This piece, whose shape is generally hexahedral, consists essentially of a mass of nonporous refractory material that has a number of local discontinuities 8 extending throughout the piece along its height h between the surface in contact with the molten metal and the opposite surface. In an advantageous method of embodiment, the local discontinuities 8 are obtained by an assembly 1, in a metal casing, of nonporous refractory elements 2, in the form of plates and which are placed side by side along their large lateral surfaces, without any material gaskets or seals between them.The piece according to the invention is easy to make.