Process and apparatus for the compression of foundry mould material

摘要

In a process for the compression of foundry mould material, which is poured loosely over a model in a closed mould space, compressed gas acts on the surface of the mould material with a pressure of at most 8 bar, which is decompressed into the mould space from a pre-pressure space at a higher pressure through a closable opening between this and the mould space with a gas mass throughput of more than 50 kg/s and at a rate of pressure increase of more than 300 bar/s, the pressure in the pre-pressure space being at most 20 bar. An apparatus for performing the process consists of a pressure container, a mould box arranged below it with filling frame and model plate with model, and a valve, between the pressure container and the mould space, having an opening cross-section amounting to 50-150 % of the horizontal mould box cross-section and released by a closure element in a few milliseconds.