| 摘要 |
PURPOSE:To contrive to improve the producibility without requiring a vacuum furnace and the like by a method wherein a space is formed by welding a member surrounding the brazing part of an exhaust valve and the like with an exhaust valve and the like in periphery direction, then the brazing is performed by adjusting the atmosphere of said space. CONSTITUTION:A covering plate 15 is welded in circumferential manner to surround a seat member 14 extending over a stem part 11 of an exhaust valve A and a seat part 13. An air removing pipe jointed with a vacuum pump is jointed to the covering plate 15. A nickel brazing material and the like are inserted in the space between the seat part 13 and the seat member 14. An air is removed from the space surrounded by the seat 13, the seat member 14 and the covering plate 15 under above condition, then the air removing pipe is sealed. Thereafter, the brazing is performed under heating condition kept by an electric furnace in the open air, then the covering plate 15 is removed. Thus, the expected object can be achieved by brazing the local part to be brazed under the vacuum, inactive gas or reduced gas atmosphere condition. |
