Vacuum chambers provide bulk vacuum drying and degassing capability with the possibility of chamber air extrusion by inert gas. Vacuum ovens can be used not only for heat labile and oxidation sensitive substances (i.e. powders, granulates and others) but also for pieces with hardly accessible openings and threads. These units are ideal for drying of samples up to a constant mass. They are to be used especially in the field of polymer processing, in pharmaceutical, chemical, electrical and other industries.