Back diffusion preventer for tubular - furnace

摘要

The arrangement blocks diffusion of atmospheric air into open processing tube which is swept by a stream of protective gas. Tubular furnace of this kind is used for making of semi-conductor materials. The gas outlet end of the tube is screened by a flow of gas issuing from a number of holes in a toroidal ring which is placed in an adaptor for extending tube length. A gap in the toroidal ring allows passage of crucibles used in the process.