| 摘要 |
PROBLEM TO BE SOLVED: To provide a nuclear reactor coolant pump capable of controlling circulation of pressurized water of high temperature and high pressure in abnormal circumstances.SOLUTION: A nuclear reactor coolant pump is provided with a rotary shaft 1, a housing which surrounds the rotary shaft 1, and a leakage preventing seal 30 which is installed so as to demarcate a gap between the rotary shaft 1 and the housing and controls the circulation of high temperature pressurized water at abnormal circumstances. The leakage preventing seal 30 includes: a C-shaped seal ring 31 extending in a circumferential direction of the rotary shaft 1 so as to surround the rotary shaft 1, and having a first end part 41 and a second end part 51 which are independent of each other; and a thermal actuator 60A which is driven by the high temperature pressurized water as heat source and reduces a diameter of the seal ring 31 by changing relative positions of the first end part 41 and the second end part 51 in the circumferential direction. |
