Abstract: An erosion resistant refractory mortar composition is described which is suitable for bonding a zirconia insert in an alumina graphite plate of a sliding gate valve. The refractory mortar is made from a mix consisting of, in weight percent, about 50%-85% zirconia; about 15%-50% alumina; up to 5% chromium oxide; up to 6% phosphoric acid plus an effective amount of a binder. Sufficient water is added to provide proper plasticity to the mix.

Abstract: The invention concerns a material for covering the metal contacting surfaces of casting elements such as slide gate valves and casting nozzles and shrouds to resist steel erosion and alumina deposition during the continuous casting of aluminum killed steel.It is comprised of a fused mixture of calcium oxide and zirconia, with a calcium oxide content of between about 20% and about 60% by weight and preferably between about 20% and about 50% by weight, the composition may include a binder producing carbon/carbon bonds by sintering. The material may also include a ceramic bond or may be applied as a fused layer by plasma spraying.

Abstract: The invention concerns a material for the covering of casting shrouds.It is comprised of a calcareous composition capable of liberating calcium oxide at a temperature at least equal to 1400.degree. C., its calcium content, expressed in calcium oxide, is between ca. 10% and ca. 60% and preferably between ca. 20% and ca. 50%, the said calcareous composition is bound by a binder chosen in the group comprised of those utilizing carbon/carbon bonds by sintering.Application to the metallurgy of ferro-alloys.

Abstract: A one-piece refractory stopper rod has an axial bore formed therein for the introduction of inert gas into molten steel within a tundish. A metal bushing insert is copressed into the refractory stopper rod and has a threaded bore which is positioned coaxially with the bore of the stopper rod body. A metal attachment rod having an axial bore therethrough and a threaded lower shank portion is secured within the threaded bore of the metal bushing insert. The metal attachment rod has an upper threaded shank which is adapted to be secured to a stopper rod lifting mechanism associated with the tundish. The metal rod further includes a flanged portion intermediate the upper and lower shank portions which carries an annular chamfered surface. The annular chamfered surface faces a like annular chamfered surface formed in the bore of the stopper rod to define a gas-tight seal at a sealing interface therebetween.

Abstract: A one-piece refractory stopper rod has an axial bore formed therein for the introduction of inert gas into molten steel within a tundish. A metal bushing insert is compressed into the refractory stopper rod and has a threaded bore which is positioned coaxially with the bore of the stopper rod body. A metal attachment rod having an axial bore therethrough and a threaded lower shank portion is secured within the threaded bore of the metal bushing insert. The metal attachment rod has an upper threaded shank which is adapted to be secured to a stopper rod lifting mechanism associated with the tundish. The metal rod further includes a flanged portion intermediate the upper and lower shank portions which carries an annular chamfered surface. The annular chamfered surface faces a like annular chamfered surface formed in the bore of the stopper rod to define a gas-tight seal at a sealing interface therebetween.

Abstract: The invention is directed to improved carbon containing refractory compositions and sintered bodies made therefrom which are particularly resistant to slag and metal erosion and to thermal shock. This is achieved by combining grains or powders of SiAlON and/or silicon nitride with elemental carbon in the form of graphite, carbon black or charcoal. The particulate materials are mixed with a carbonaceous binder such as resin or pitch, pressed to shape and fired in a reducing atmosphere. Small amounts of antioxidants are also added to protect the carbon bond phase against slag attack. Additional amounts of a less expensive refractory grain or powder are also optionally added to the mix to dilute the more expensive SiAlON and/or silicon nitride.

Abstract: A ladle shroud has a co-pressed porous ring for the introduction of an inert gas at the sealing joint between the ladle shroud and a mating ladle collector nozzle. The dense body of the ladle shroud and the co-pressed porous ring are of similar carbon-bonded graphite refractory grain compositions and have similar carbon containing binder systems to improve the bond between the ring and body components. The dense body further includes a continuous integral ledge portion which, abuts a top surface of the porous ring to seal the top of the ring against unwanted inert gas leakage.

Abstract: A one-piece carbon-bonded graphite refractory stopper rod for use in continuous casting of molten metal includes a copressed body portion with an integral porous nose section. Through a gap grain sizing technique, the mean pore size of the nose is controlled to preferably about 10 microns to permit an inert gas introduced into the rod to permeate therethrough as a fine dispersion of bubbles in the melt while preventing reverse permeation of molten metal in the event of depressurization of the gas supply. Improved erosion resistance of the nose and lower alumina deposition in the casting nozzle are also achieved.

Abstract: The present invention provides a refractory tube through which a stream of molten metal is passed during continuous casting which includes an inner refractory member of relatively low thermal expansion and thermal conductivity characteristics and an outer refractory member of high erosion resistance. The cooperation of the inner and outer refractory members results in an end product with a prolonged useful casting life and which does not require preheating prior to use. In a preferred embodiment, the inner refractory member is formed of fused silica and the outer refractory member is formed of alumina graphite and/or zirconia graphite.

Abstract: An elemental carbon-containing refractory composition having superior erosion and oxidation resistance due to the addition of prescribed amounts of boron carbide.

Abstract: A nozzle is provided having an elongated conduit extending therethrough for delivering molten metal below the surface of a pool of molten material. The nozzle includes facilities for passing a fluid medium, e.g., argon, through its wall members transverse to the direction of molten metal flow into the elongated conduit to retard the accumulation of undesirable formations, e.g., metal oxides, on the inner wall surfaces of the conduit during molten metal flow. In a first embodiment, gas permeable wall members define portions of the conduit through which the fluid medium percolates. In a second embodiment, a plurality of small ports are provided in the wall members defining the conduit through which the fluid medium is emitted in the conduit. Preferably, the nozzle also includes a base portion that directs the molten metal flow in an upwardly direction and which has facilities for retarding the accumulation of undesirable formations thereon.