| 摘要 |
PROBLEM TO BE SOLVED: To easily and surely cool a reactor pressure vessel when a water level in the reactor pressure vessel of a boiling water reactor lowers a critical level. SOLUTION: A differential pressure measuring pipe (8) is provided outside the reactor pressure vessel and a reverse U-shape pipe is formed by connecting the first pipe leg (8A) and the second pipe leg (8C) of the pipe at above the critical water level (K). The first pipe leg is let pass a inner room (4) of the reactor pressure vessel at the critical level height. The differential pressure measuring pipe is fully filled with water during normal operation. When the water level lowers the critical level, water is automatically drained out of the differential pressure measuring pipe. In this manner, the differential pressure between the first pipe leg and the second pipe leg is raised and the differential pressure is measured with a measuring device (18) to initiate immersion into an outer room (6) of reactor pressure vessel with the device. COPYRIGHT: (C)2003,JPO
|
