Patent ID: 8302656

Claim:
A method of casting a molten metal into a mould using an apparatus which has a casting chamber which includes a mould into which molten metal is introduced when the casting chamber is at least partially evacuated, to fill the mould, a tundish connected to the casting chamber, the tundish having an opening in register with an inlet aperture of the casting chamber to provide an inlet flow path for the molten metal from the tundish into the casting chamber, a plug which includes a sealing part of a material with a melting temperature not greater than the temperature of the metal being cast, and an interchangeable nozzle in the inlet aperture which has a through opening of a fixed size, the method including selecting a nozzle for engagement in the inlet aperture in order to achieve an optimum flow rate of molten metal into mould, locating the plug to close the molten metal flow path, at least partially evacuating the casting chamber, pouring a volume of molten metal into the tundish sufficient to fill the mould whereby at least the sealing part of the plug melts to permit molten metal to flow along the flow path through the nozzle into the casting chamber.