| 摘要 |
PURPOSE:To enhance an economical property and to prevent the generation of sooting by a method wherein a mixed gas of nitrogen and oxygen is purified by using nitrogen gas generator using an adsorbing agent and a hydrocarbon such as propane or the like is added to said mixed gas to form a carrier gas. CONSTITUTION:A door 4 of a front purge chamber 3 is opened to convey an article 11 to be treated thereinto and closed. A pressure in the chamber 3 is reduced by a vacuum pump and a mixed gas consisting of, in a volume ratio, 95-99% Nitrogen and 1-5% Oxygen purified in a nitrogen gas generator is introduced into the chamber 3 to replace air with the introduced gas. Subsequently, a door 2 and an heat insulation door 4a are opened to communicate the front purge chamber 3 and a heat raising chamber 5 and the article 11 to be treated is sent to the heat raising chamber 5 to be heated therein. The heated article 11 to be treated is sent to a carburizing chamber 6 by opening the heat insulation door 4b and, after said carburizing chamber 6 is hermetically closed, a gas prepared by adding a hydrocarbon such as propane or the like to the aforementioned mixed gas is filled in said chamber 6 to carry out the carburization. |
