HOT TEMPERATURE HEAT TREATMENT PROCESS AND HOT TEMPERATURE HEAT TREATMENT FURNACE

摘要

PURPOSE:To reduce a required amount of inner gas for carrier by a method wherein a controlled pressure is applied to a lid of muffle which can be opened or closed and then the lid is abutted against a main body of the muffle. CONSTITUTION:A lid 23 of a muffle 21 having a processed material fed therein is abutted against a main body 22 with a controlled pressure from a compressed air supplying source 59. Inert gas for carrier fed from the supplying source 16 through a control valve 15 and a feeding port 14 passes through a small clearance between the main body 22 of the muffle and the lid 23, flows into the muffle 21 and then is discharged out of the furnace from a discharging port 24 together with harmful gas generated in the muffle. In turn, as the main body 22 is thermally expanded, the lid 23 is moved smoothly while keeping its abutted state against the main body 22 with a controlled pressing pressure and then it discharged a compressed air corresponding to a surplus pressure. With such an arrangement, it is possible to eliminate the required amount of inert gas more than that in the conventional system.