Abstract: An apparatus and method is presented for emptying metallurgical vessels, and in particular steelmaking converters containing metal and slag, whereby the slag is effectively separated from the metal during pouring. The apparatus includes at least on permeable refractory element located near the flow hole. An agitating gas is fed through the refractory element thereby creating a bubbling froth which effectively obstructs most of the slag from being carried along by the vortex which forms above the vertical flow hole.

Abstract: A nozzle for refining metals or ferroalloys by oxygen blasting from above the melt is presented. The nozzle terminates at a nozzle head and includes at least one central blast pipe for directing a jet of oxygen having supersonic speed. A chamber is interposed between the mouth of the blast pipe and the mouth of the nozzle head. This chamber widens progressively from the mouth of the blast pipe, and narrows toward the mouth of the nozzle head. At least one opening from at least one lateral duct opens to the chamber in the vicinity of the blast pipe mouth. Each lateral duct is connected to a source of gas, and includes an inidividual flow control valve. Preferably, at least three lateral ducts are arranged symmetrically around the blast pipe mouth.

Abstract: A blast pipe for delivering refining oxygen to the space above a metal bath in a refining operation is presented. The blast pipe is positioned in a gas supply duct and is provided with a pressure regulating valve. The blast pipe comprises a fixed straight wall portion along which the gas flows in a linear path. The straight wall portion terminates at a sharp edge, constituting a portion of the blast pipe exit orifice. A bent wall segment is located adjacent to and downstream of the straight wall portion and connects the remainder of the straight wall portion to the exit orifice. The bent wall segment preferably has a convergent configuration, upstream of the sharp edge, and a divergent configuration downstream thereof. The exit orifice, in cross section, has the shape of a rectangle, one of the long sides of which constitutes the sharp edge.

Abstract: A nozzle for the refining of metals by oxygen blasting from above the melt is presented. The nozzle includes a nozzle head having a blast pipe therethrough upstream of the mouth of the nozzle. The blast pipe directs a jet of gas comprised, at least in part, of oxygen, having a supersonic speed onto the melt. The blast pipe includes an inner tube. The lower portion of the inner tube has a throat positioned between a convergent and divergent sections, this lower portion defining a laval nozzle. The blast pipe also includes an outer tube coaxial with the inner tube and having a greater cross section than the inner tube. The mouth of the inner tube is spaced back (downstream) from the mouth of the blast pipe. The inner and outer tubes are each provided with flow control valves, and are connected to sources of pressurized gas. Devices are provided to vary the cross sectional area of the mouth of the inner tube.

Abstract: A gas-permeable element of a refractory material for blowing gases into a metal treatment vessel through its lining has a body of a refractory material, a metal housing on the longitudinal sides of the refractory body, a free inner end surface at which the refractory material is exposed, an outer end surface provided with a gas distributing chamber for a gas supply, at least one local opening extending in the interior of the refractory body for a gas passage between the end surfaces and provided with a metal insert, wherein the metal insert is formed as a laterally closed small channel, the gas-distributing chamber is separated from the refractory material by a metal sheet plate, and the metal channel is tightly mounted in the metal sheet plate so that the refractory material is maintained free from loading with a gas pressure.

Abstract: Apparatus for closing the discharge aperture of a metallurgical vessel is presented. This apparatus includes a closure element attached to a pivoted lever in order to prevent undesirable discharge of slag at the beginning and end of the casting process and during refining. The lever pivotally opens and closes the aperture by means of a piston rod and pressure cylinder. The closure element, preferably made from wood, is temporarily attached to the lever by a friction fit and is designed to be used only once.

Abstract: A method of and an apparatus for the refining of a molten metal overlain by a slag and in which cold solids are introduced, e.g. in the form of metal scrap. According to the invention the heat necessary to melt the scrap and prevent undue cooling of the bath is generated by directing a jet of neutral gas entraining carbon against the surface of the melt perpendicularly thereto at Mach 1.5 to Mach 2.5, while refining oxygen is directed at the surface from jets inclined to the carbon entraining jet and the melt is bottomblown by neutral gas to prevent excessive foaming of the slag.