Molten metal flow control

Abstract

Metal flow control for a continuous casting process is provided by providing a gas back pressure bubble to block the flow of molten metal above the casting nozzle. Pressurized gas is provided to a cap positioned upstream of the nozzle and including a depending skirt that cooperates with a dam. When the gas pressure offsets the head pressure of the molten metal, the flow of molten metal into the nozzle is blocked. By terminating the control pressure, the flow of metal over the dam may be reestablished. The cap including the skirt and the dam form a weir assembly defining a channel along one side or around the periphery of the nozzle. The cap may be supported and fed with gas pressure through a duct from the side, or along the center of the crucible.

Dependencies are inferred from the claim text.