Abstract: A two stage reaction for the production of steel from iron carbide is carried out in two separate but interrelated reactors. In the first reactor, iron, carbide, with slag formers, is fed into a feed end and the reaction is well-mixed by the vessel geometry, the stirring action below-surface injection of oxygen and iron carbide feed, and the evolution of gases from the liquid metal bath. The product, containing about 0.5-2% carbon, is fed into the second reactor where it is refined with subsurface-injected oxygen. The second reaction is autogenous, and the evolved carbon monoxide is fed to the first reactor where it is burned with oxygen in a foamy slag, which, with post-combustion burning in the slag of CO evolved in the first reactor, and with iron carbide preheating with the sensible heat of the off-gas from the first reaction, makes that reaction also essentially autogenous.

Abstract: A two stage reaction for the production of steel from iron carbide is carried out in two separate but interrelated reactors. In the first reactor, iron carbide, with slag formers, is fed into a feed end and the reaction is well-mixed by the vessel geometry, the stirring action below-surface injection of oxygen and iron carbide feed, and the evolution of gases from the liquid metal bath. The product, containing about 0.5-2% carbon, is fed into the second reactor where it is refined with subsurface-injected oxygen. The second reaction is autogenous, and the evolved carbon monoxide is fed to the first reactor where it is burned with oxygen in a foamy slag, which, with post-combustion burning in the slag of CO evolved in the first reactor, and with iron carbide preheating with the sensible heat of the off-gas from the first reaction, makes that reaction also essentially autogenous.

Abstract: Ingress of gas such as air through the joint of a pour tube and tube holder of a continuous caster is prevented or inhibited by passing an inert gas into a circumferential channel around the orifice and at the interface of the joint; the gas is evenly distributed within the channel over the entire configuration of a porous refractory insert in the circumferential channel; the porous refractory insert assures even distribution of the gas to the desired location in the joint.

Abstract: In the continuous casting of steel, gas is prevented or inhibited from contacting molten steel through the valve slide plate by feeding inert gas through channels in the slide plate and adjacent parts; the channels contain porous refractory inserts and can be connected to outside sources through juxtaposed side channels.

Abstract: Undesirable deposits of precipitated alloying materials are avoided in a sliding gate valve apparatus of the type in which gates are sequentially moved to and from operative position between the pour opening of a teeming vessel and a pour tube assembly for conducting molten metal from the valve apparatus, by forming the gates with through-openings whose axes are inclined in the direction of gate movement to and from their operating position in the valve apparatus, and forming the flow passage in the tube holder of the pour tube assembly with an opening extended in the direction of gate movement. The configuration of the particular gate and pour tube holder constructions are also disclosed.

Abstract: A vessel used for transfer of molten metal having a refractory filter wall with filters for removing inclusion from molten metal as it flows through the vessel. The refractory filter wall having passages sized according to a predetermined volume of molten metal that is to be filtered, the desired flow rate of molten metal through the vessel and the limiting characteristics of the filters. In another aspect of the invention, protrusions are provided on refractory walls of the vessel to enhance deposition of non-metallic inclusions on the protrusions by disrupting the boundary layer flow in the molten metal.

Abstract: A refractory article is provided for the prevention of vortexing in molten metal as it is drained through a nozzle in a metallurgical vessel. The article has at least one rib extending substantially radially outwardly from an opening therein for draining of molten metal from the vessel, said rib protruding upwardly from an inner surface of the article so as to prevent the formation of rotating boundary layer flow within the molten metal.

Abstract: A pouring pad is provided for use in a tundish during sequence continuous casting. The pouring pad has a plurality of concentric primary ridge portions adjacent to the location of impact of a pouring stream from a ladle with the pad. The primary ridge portions are of a height within a range for creating pockets of recirculation so as to dissipate turbulence without deflection of molten metal from its radially outward flow along the pad. The radial spacing between adjacent primary ridge portions as measured between top inner edge surfaces at corresponding radial points is at least 2.0 times the height of the inner of the adjacent primary ridge portions.

Abstract: A feed system is provided for conveying molten metal to a thin section caster having mold surfaces moving exclusively in the direction of casting. The feed system has a passage of circular cross section adjacent to one end thereof for receiving molten metal and a rectangular cross section at the delivery end thereof adjacent to the caster. The feed system is designed for supplying molten metal to the caster at low pressure for "closed-pool" type caster operation. The point of highest elevation in the metal flow passage of the feed system is on the upper surface of a transition portion where the cross section changes from circular to rectangular adjacent to the nozzle. The level or height of the high point above the centerline of the nozzle exit is selected so as to be less than the pressure of the metal measured in inches at the nozzle exit. This feature enables the maintenance of positive pressure in the metal within the feed system so that ingress of air into the metal is prevented.

Abstract: A refractory article is provided for the prevention of vortexing in molten metal as it is drained through a nozzle in a metallurgical vessel. The article has at least on rib extending substantially radially outwardly from an opening therein for draining of molten metal from the vessel, said rib protruding upwardly from an inner surface of the article so as to prevent the formation of rotating boundary layer flow within the molten metal.