Abstract: A refractory roll cover is described that reduces the amount of noxious dust during the production of glass sheet. The roll cover comprises a plurality of segments, including low dusting millboard segments mechanically supported by highly rigidized compressed fiber segments. The millboard segments are adapted to contact the glass sheet. The millboard is chosen so that any dust produced has little affinity for the glass sheet or is not easily fluidized by convective currents. The highly rigidized compressed fiber has a fused surface that releases little dust. The resultant roll cover substantially eliminates dusting while providing a mechanically superior roll cover.

Abstract: The present invention relates to a ladle block for use in a bottom of a molten metal ladle. The ladle block reduces the amount of contaminants, particularly slag, exiting the ladle during casting operations. The ladle block includes a floor defining an outlet and sidewalls substantially orthogonal to the floor. The floor and sidewalls define a channel having dimensions of length, width and height. Channel dimensions are determined from the Froude number, which is based at least partially on the casting flow rate.

Abstract: The present invention relates to a metallurgical ladle and more particularly to the bottom of the ladle having an outlet through which the molten metal can drain. An object of the present invention is to increase the efficiency of a ladle draining operation, including reducing the amount of discarded metal, avoiding the premature flow of slag through the outlet, and reducing the contamination of slag in the molten metal effluent. The ladle bottom comprises a plurality of terraces and flow channels, ultimately directing the stream of molten metal to an outlet of the ladle. The terraces are described as capturing slag and the channels permit molten metal to flow preferentially through the outlet.

Abstract: The invention describes an article and method comprising a refractory article having an outer surface covered by an insulating coating over which a protective glaze is applied. The method includes applying a suspension of an insulating coating to a refractory piece, drying the suspension, applying a glaze slip over the coating, and drying the slip to form a protective glaze. In one embodiment, the article comprises a carbon-bonded alumina-graphite nozzle, an insulating coating containing hollow microspheres, and a protective glaze formed from a fusible frit. The invention is described as improving wetting to the refractory piece, reducing delamination of the glaze and insulating coating from the piece, and reducing oxidation of the piece.

Abstract: A permeable, resin-bonded composition is described, which finds utility as a porous element in a gas-injection nozzle. The permeable composition is notably useful in a canless, resin-bonded, gas-injection nozzle, characterized by an impermeable, resin-bonded composition replaces the metal can. Advantageously, the resin-bonded compositions include an oxygen getter for scrubbing oxygen before the oxygen can reach the molten steel. A method of manufacturing the nozzle is described and includes copressing a standard, resin-bonded composition around the permeable, resin-bonded composition. The pressed piece may be cured at temperatures below about 800° C.

Abstract: The present invention relates to a pouring nozzle (1) for a device for nozzle insertion and/or removal whose shape is adapted so as to better resist the stresses imposed by their use and notably the stresses linked to the maintain of the nozzle in the device. The pouring nozzle is provided with two bearing faces forming with the pouring channel an angle ? of 20° to 80°. The present invention also relates to a pushing device for the pouring nozzle and to a casting installation embodying said nozzle and device.

Abstract: A tundish impact pad for use in the continuous casting of molten metal is described that includes a base plate having an upper impact surface surrounded, at least in part, by a sidewall defining passageways. The impact pad is adapted to receive and deflect an incoming stream of molten metal, and permit outflow of the deflected stream through the passageways and the open top surface of the pad. Vaulted-stepped features surrounding the passageways and/or weir-like walls assist in directing the outflow. The division and distribution of the outflow facilitates the development of plug flow in the molten metal between the impact pad and the tundish outlet.

Abstract: The invention relates to a filter device for molten steel filtration and a process for the preparation thereof. The filter device (1) comprising a bonded network of graphitized carbon for molten steel filtration characterized by the presence of at least two sieve plates (2, 4) spaced apart to each other, in particular providing a reservoir chamber 7.

Abstract: The present invention relates to a fiber reinforced ceramic filter for molten metal filtration that comprises a bonded network of graphitized carbon and a method for producing such filters.

Abstract: The invention relates to an injection device for the reliable introduction of a fluid into a metallurgical vessel having a refractory lining, the device being removably insertable in the lining; comprising a refractory first body (2) and a refractory second body (3) fittingly assembled, the first body (2) being made of a refractory material less permeable to the fluid than the material of the second body (3), the first and second bodies having each a surface (4, 5) adapted to contact molten metal; and having each fluid passages (6, 7) extending from fluid feeding means (8) to a surface (4, 5) adapted to contact molten metal, the relative flow resistance of the fluid passages (7) in the second body (4) being higher than that of the fluid passages (6) in the first body (2), the fluid passages (6) in the first body (2) being constituted of slots or bores. According to the invention, the fluid passages (6) in the first body (2) are independent from the fluid passages (7) in the second body (3).

Abstract: The mould (10) includes at least one part (20), intended to be in contact with the component (12) being moulded, made from sintered vitreous silica. According to the process, said component (12) is formed by the superplastic forming in the mould (10) of a plate (18) made of a material capable of undergoing superplastic deformation, for example titanium or titanium alloy, aluminium or aluminium alloy, or any material exhibiting superplastic properties. Preferably, a barrier is formed between at least a part of the contact surfaces of the mould (10) and the component (12) being moulded, for example by coating with boron nitride, at least partially, the contact surfaces of the mould (10) and the component (12) being moulded, before placing the plate (18) in the mould (10), and/or by injecting an inert gas, notably helium or argon, between the contact surfaces of the mould (10) and the component (12) being moulded.

Abstract: There is provided a refractory mono-block stopper of substantially cylindrical configuration having an upper end, a lower end and an axial bore extending downwardly from the upper end, means being provided in the axial bore at a distance d from the upper end for attachment of the stopper to a lifting mechanism, the stopper being divided into three portions (A,B,C); a first portion (A) extending from the upper end towards the lower end until a distance greater than d, a second portion (B) extending from the first portion (A) towards the lower end and a third portion (C) extending from the second portion (B) and comprising a stopper nose ending at the lower end of the stopper. The stopper of the invention is characterized in that the average section of the second portion (B) is lower than the section of the first portion (A) and the highest section of the third portion (C) is higher than the lowest section of the second portion (B).

Abstract: The present invention relates to a metallurgical ladle and more particularly to the bottom of the ladle having an outlet through which the molten metal can drain. An object of the present invention is to increase the efficiency of a ladle draining operation, including reducing the amount of discarded metal, avoiding the premature flow of slag through the outlet, and reducing the contamination of slag in the molten metal effluent. The ladle bottom comprises a plurality of terraces and flow channels, ultimately directing the stream of molten metal to an outlet of the ladle. The terraces are described as capturing slag and the channels permit molten metal to flow preferentially through the outlet.

Abstract: The invention relates to a refractory plate (1) for a slide gate valve, having a pouring hole (3), circumscribed by a circle C of center (4), at least a portion of the edges (15, 16, 17, 18) of the plate (1) are angularly oriented so as to focus the clamping forces optimally in the throttling area and around the pouring hole.

Abstract: A metering gate for liquid metal flow control with reduced clogging with a top plate, having a first flow channel bore with an inlet having an inlet axis and an outlet having an outlet axis. The inlet axis and the outlet axis are offset. A throttle plate slidably mounted on the top plate selectably receives flow from the top plate. The metering gate provides a less tortuous and more symmetrical flow path when the gate is partially open, but provides a relatively straight downward flow channel allowing full flow when the gate is fully open.

Abstract: The present invention relates to a clamping device including at least two assemblies each composed of a clamp (10) pivoting about a horizontal axis (11) and fitted with a groove (12) receiving a shoe (13) generally cylindrical in shape incorporating a flat surface (14) parallel to the axis of said cylinder, said shoe being capable of pivoting in the groove. The present invention also relates to a one-piece inner nozzle (2) particularly adapted for use with this clamping device. The one-piece inner nozzle according to the invention is thus composed of a tubular part (6) defining a pouring channel (4) and a flat part or plate (7) providing contact with the downstream component (8) of the pouring channel.

Abstract: The invention relates to a refractory bearing and in particular to a bearing for use in contact with molten metal, such as zinc and aluminum. The bearing includes a housing with a working surface and at least one wear-resistant insert secured to the working surface. The insert is secured to the housing by mechanically interlocking with a retainer assemblage. In one embodiment, the retainer assemblage engages a relief in the insert to secure the insert to the housing despite dimensional changes caused by thermal expansion. The insert preferably comprises sialon.

Abstract: The present invention relates to a grooved refractory pouring tube for pouring a molten metal between an upper metallurgical vessel and a lower metallurgical vessel, a refractory assembly incorporating such a pouring tube, and a casting installation incorporating such an assembly.

Abstract: The present invention provides a composite pressure-sintered material comprising a continuous phase of hexagonal boron nitride and, dispersed therein, a second material comprising (a) at least one metal nitride selected from the group consisting of silicon, aluminium and titanium nitrides and (b) at least one stable metal oxide; wherein the amount of metal oxide is such that the second material does not contain more than 35% by weight of oxygen. This material possesses a low thermal expansion coefficient and therefore reveals good thermal shock resistance. Another characteristic of this material is its low wettability by molten steel which is thus responsible for excellent chemical resistance to liquid metal. Finally, this material is exceptionally mechanical wear resistant.

Abstract: A nozzle for transferring a flow of liquid metal between metallurgical vessels or molds comprising an entry portion for receiving the liquid metal. A flow regulator, such as a stopper rod, is movable from an open position to a closed position with respect to the entry portion for respectively permitting and prohibiting flow through the nozzle. The entry portion and the flow regulator define a control zone therebetween. A pressure modulator, downstream of the control zone, is adapted to minimize a pressure differential across the control zone. The pressure modulator constricts flow downstream of the control zone.