fireproof device for providing a passage for the casting of molten me language from a gietvat and a method for preventing the accumulation of oxydeinsluit systems on thestromingsoppervlak of a nozzle opening.

摘要

A description is given of a method in which, by means of a special structural configuration of the restriction orifice in the flow duct of a casting vessel, it is possible to avoid an accumulation of oxidic impurities. For this purpose, the restriction orifice is given an axial length which is shorter than the constriction of the casting stream which it causes, known as the "vena contracta". Provided above this restriction orifice is a chamber which slows down the flow of the molten metal and calms turbulence. A description is furthermore given of an apparatus for carrying out this method, in which use is made of a flat disc (40) which is provided with the restriction orifice (42) and is arranged in such a way in the through hole for the passage of the molten metal that a chamber (38) is formed above the flat disc (40). IMAGE