Abstract: Moulding flask adapted to be used in a process for forming a mould comprising steps of disposing, at the opening of the moulding flask, a pattern having a shield membrane of synthetic resin on the outer surface thereof, filling the space defined between the moulding flask and the pattern with particulate filler material such as sand, and applying negative pressure to the filler material so that the filler material is subjected to an external pressure to make a mould, said moulding flask having at least one surface on an intermediate partition surface formed by an impervious resilient membrane which is supported by a support member whereby, when the filler material is subjected to the negative pressure, the external pressure is applied to the resilient membrance which then presses the filler material so as to enhance compacting of the mould thus producing a strong and precise casting mould.

Abstract: A vacuum sealing for the discharge nozzle of a casting ladle as for liquid steel is disclosed. The vacuum sealing, which prevents the penetration of atmospheric gases through the porous refractory discharge nozzle, is arranged in a vacuum-tight manner below the discharge nozzle. The vacuum sealing consists of clingy plastic films or thin metal sheets.