| 摘要 |
PROBLEM TO BE SOLVED: To provide a motor casing of a reactor coolant recirculation pump in which a pump nozzle and an opening end of a small diameter part of a motor casing are easily centered and welded and further in which an inner peripheral surface of a pump nozzle skirt and a protrusion for centering a lower side of the small diameter part of the motor casing contact with each other less strongly due to pressure rise and heat expansion in a reactor pressure vessel.SOLUTION: A motor casing 7A is provided with an almost annular protrusion 9A having a cutout part 9a at an opening angle A, for example, at a range of 100°, to a center line 5 in a radially outward side of a bottom of a reactor pressure vessel 1 of a small diameter part 7b. The almost annular protrusion 9A has the same radial height as a conventional annular protrusion. |
