| 摘要 |
PURPOSE:To prevent crack generation at a key seat on impeller side owing to stress corrosion by setting a blocking plate firmly between impeller and an axle on which the impeller is fitted by means of hot pressure process and by equipping this blocking plate with a nozzle and plug for encapsulation of inert gas. CONSTITUTION:Impellers 2, 3 are fitted on an axle 1 by means of hot pressure process, and a blocking plate having expansivity 8 is set firmly between these impellers 2, 3 by welding 9, 10. Further, this blocking plate 8 is furnished with a nozzle 12 and plug 13 for the purpose of encapsulating inert gas. Thereby flowing-in of steam into a gap 6 between the axle 1 and impellers 2, 3 is hindered as well as crack generation at the key seat owing to stress corrosion, prevented. |
