| 摘要 |
PURPOSE:To perform washing and heat treatment effectively by providing a pretreating chamber on the upper stream side of a heat treating chamber, heating and washing treating objects with a nonoxidative gas, thence transferring the objects together with the nonoxidative gas into the heat treating chamber and heat treating the same. CONSTITUTION:The vacuum door 9 of a pretreating chamber 5 is opened, and treating objects 11 are transferred by an insertion table 12 into the chamber 5, thence the door 9 is closed. The inside of the chamber 5 is evacuated to the highest possible vacuum by a vacuum pump 16a, and the objects 11 are washed under heating with heaters 4. Thence, gaseous nitrogen is supplied from a gaseous nitrogen vessel 18, and is kept under the pressure higher than the pressure in the chamber 2. The objects 11 are transferred together with the gaseous nitrogen from an intermediate door 7 into the chamber 2. The inside of the chamber 2 is heated to prescribed temps. by heaters 1, and gaseous nitrogen is supplied therein. If necessary, a carburizer, a nitriding agent or gaseous oxygen is suitably supplied from a heat treating agent supplying chamber 21, whereby heat treatment is accomplished. Next, the objects are conveyed into a cooling chamber 24, the inside of which is evacuated and is substituted with gaseous nitrogen, whereby cooling is accomplished. |
