Vacuum drying appts. with programmed control of temp. - is subject to adaptive control allowing for mathematical relationship between residual pressure and surface temp. variation

摘要

An infrared radiator (4) is heated continuously to a basic temp. and after starting of the vacuum pump the b.pt of water is attained quickly as pressure in the vessel (1) falls. A pressure transducer (7) starts the stored-program control (6) of heating so that the articles (2) are dried at a constant temp. measured by a probe (3). For porous articles heat is produced by microwave electrodes with regulated field strength. USE/ADVANTAGE - With heat-sensitive capillary and porous filter elements or metal-plastics composites, drying time is shortened and overheating prevented with less complex vacuum appts.