| 摘要 |
PURPOSE:To enhance the productivity of heat treatment, by a method wherein an elastic expansible bag is provided in a heat treating furnace and the exhausion of an existing gas in the furnace and the supply of a treating gas are carried out through the expansion and the contraction of said bag to shorten a gas replacing time. CONSTITUTION:To a pair of rubber elastic expansible bags 6 provided in a furnace body 2, a nitrogen gas B is gradually supplied through a solenoid valve 7 and the rubber bags 6 are gradually expanded to exhaust an existing gas A to the side of a exhaust port 4. Further, the rubber bags 6 are fully expanded to completely exhaust the existing gas A. In the next step, the expanded rubber bags 6' are contracted to be restored to the original states while the nitrogen gases in the bags 6' are gradually exhausted and a treating gas such as a carburizing gas C is supplied from a gas supply port 3 to fill the interior of the furnace body 2. By this method, the heat treating gas can be infiltrated into the furnace body 2 without mixing the existing gas. |
