Joint structure of pedestal for supporting reactor pressure vessel and vent pipe

摘要

(57) [Summary] [Purpose] To reduce the stress concentration points in the vent pipe and the thermal effects on the bottom concrete. [Structure] The vent pipe 12 is opened at the upper end of the pedestal 3 and extends downward in the pedestal 3 to a height position where a predetermined space is provided on the bottom concrete 2, and the pedestal 3 is provided at one position on the lower end of the vent pipe 12. Extends substantially horizontally in the radial direction of Further, the vent pipe horizontal portion 13 opening to the outer peripheral surface, the vent header 14 extending along the outer periphery of the pedestal 3 so as to cover the tip opening portion of the vent pipe horizontal portion 13, and the vent header 14 And a plurality of nozzles 15 that radially project from the nozzle. [Effect] Since the vent pipe horizontal portion 13 is provided at one place, there is one stress concentration place, and since the lower end portion of the vent pipe 12 is separated from the bottom concrete 2, there is no thermal influence.