| 摘要 |
PURPOSE:To recover the creep deterioration without scraping the surface of the hole in the center by cold- or hot-rolling the inner surface of the center hole of the steam turbine rotor wherein the creep deterioration is progressing. CONSTITUTION:The inner surface 2 of the center hole of the steam turbine rotor 1 which is experiencing a creep deterioration by being exposed to high temperature and high pressure is rolled while cold or hot. Thus, voids produced between grains are eliminated, and the inherent strength of the metal is recovered. Further, as the inner surface of the center hole is not scraped, its surface can stay smooth so that any stress concentration can be suppressed. |
