A nozzle assembly, for a metal casting apparatus selected from a sliding gate and a tube exchange device, comprises a first refractory element comprising a first coupling surface which includes a first bore aperture, and a second refractory element comprising a second coupling surface, which includes a second bore aperture, the first and second elements being coupled to one another in a sliding translation relationship through their respective first and second coupling surfaces such that the first and second bore apertures can be brought into and out of registry to define, when in registry, a continuous bore for discharging molten metal from a molten metal inlet to a molten metal outlet of said nozzle assembly. A sealing member is provided between the first and second coupling surfaces of the first and second elements. The sealing member comprises a thermally intumescent material.

A nozzle assembly, for a metal casting apparatus selected from a sliding gate and a tube exchange device, comprises a first refractory element comprising a first coupling surface which includes a first bore aperture, and a second refractory element comprising a second coupling surface, which includes a second bore aperture, the first and second elements being coupled to one another in a sliding translation relationship through their respective first and second coupling surfaces such that the first and second bore apertures can be brought into and out of registry to define, when in registry, a continuous bore for discharging molten metal from a molten metal inlet to a molten metal outlet of said nozzle assembly. A sealing member is provided between the first and second coupling surfaces of the first and second elements. The sealing member comprises a thermally intumescent material.

In an electric arc furnace system for making steel, a method and structure (1) for eliminating teeming hang-ups and ensuring temperature homogeneity in a ladle which teems into an ingot mold by gas purging at all possible steps under both atmospheric and vacuum conditions, and (2) for preventing non-metallic inclusions from appearing in the final product by deflecting the granular material in the teeming ladle well block away from the ingot mold by a heat resistant but combustible deflector just prior to entry of the teeming stream into the ingot mold.

In an electric arc furnace system for making steel, a method and structure (1) for eliminating teeming hang-ups and ensuring temperature homogeneity in a ladle which teems into an ingot mold by gas purging at all possible steps under both atmospheric and vacuum conditions, and (2) for preventing non-metallic inclusions from appearing in the final product by deflecting the granular material in the teeming ladle well block away from the ingot mold by a heat resistant but combustible deflector just prior to entry of the teeming stream into the ingot mold.

An alumina-based filling sand for sliding nozzle comprising at least 50 wt % of mixed sand including 20 to 90 vol % of alumina sand and 80 to 10 vol % of silica sand, wherein the alumina sand has surface irregularities of 1.3 or less and comprises 50 wt % or more of an Al.sub.2O.sub.3 component.

An alumina-based filling sand for sliding nozzle comprising at least 50 wt % of mixed sand including 20 to 90 vol % of alumina sand and 80 to 10 vol % of silica sand, wherein the alumina sand has surface irregularities of 1.3 or less and comprises 50 wt % or more of an Al.sub.2O.sub.3 component.

A system for metal powder atomization comprising a refractory lined melting furnace (1) configured to melt metal into a liquid metal bath (6), in which furnace (1) a drain (3) is arranged for draining liquid metal from the bottom of the furnace. The drain (3) is configured to be closed by a stopping member. The system comprises an atomization chamber (2) configured to receive and atomize liquid metal from the melting furnace (1). The system also comprises removal means controllable from the bottom region of the furnace (1) for removing the stopping member without interfering with the surface of the liquid metal bath (6). The removal means and the stopping member are configured such that the stopping member is removable independently of the temperature of the liquid metal bath (6) using the removal means.

A system for metal powder atomization comprising a refractory lined melting furnace (1) configured to melt metal into a liquid metal bath (6), in which furnace (1) a drain (3) is arranged for draining liquid metal from the bottom of the furnace. The drain (3) is configured to be closed by a stopping member. The system comprises an atomization chamber (2) configured to receive and atomize liquid metal from the melting furnace (1). The system also comprises removal means controllable from the bottom region of the furnace (1) for removing the stopping member without interfering with the surface of the liquid metal bath (6). The removal means and the stopping member are configured such that the stopping member is removable independently of the temperature of the liquid metal bath (6) using the removal means.

A dual-chambered molten metal holding furnace is for low pressure casting; producing cast products such as aluminum alloys using a low pressure casting method; and prevention of the gas release to the molten metal and the occurrence of air bubbles in the molten metal even when pressurized gas enters a material constituting the molten metal storage container. The part of a pressurizing chamber excluding a pressurizing pipe and a molten metal output pipe is opened to the atmosphere via an air passage gap positioned above a fixed molten metal surface level position L3. The air passage gap is positioned above the fixed molten metal surface level position L3. Even if pressurized gas is seeped into the material constituting a molten metal storage container via cracks or cracking subsequently occurred in the pressurizing pipe or minute gap originally present in the pressurizing pipe, the pressurized gas seeped from the air passage gap is released to the outside of the furnace.

A dual-chambered molten metal holding furnace is for low pressure casting; producing cast products such as aluminum alloys using a low pressure casting method; and prevention of the gas release to the molten metal and the occurrence of air bubbles in the molten metal even when pressurized gas enters a material constituting the molten metal storage container. The part of a pressurizing chamber excluding a pressurizing pipe and a molten metal output pipe is opened to the atmosphere via an air passage gap positioned above a fixed molten metal surface level position L3. The air passage gap is positioned above the fixed molten metal surface level position L3. Even if pressurized gas is seeped into the material constituting a molten metal storage container via cracks or cracking subsequently occurred in the pressurizing pipe or minute gap originally present in the pressurizing pipe, the pressurized gas seeped from the air passage gap is released to the outside of the furnace.