Reactor container

In a nuclear reactor container of a BWR type power plant facility, the exterior of a reactor pressure vessel, main steam pipelines and feedwater pipelines has a double-walled structure. The gap formed between the inner side of the outer wall and the outer side of the inner wall of the exterior of the double-walled structure is in communication with pool water in a pressure suppression chamber by a transfer path. When rapture is caused in the reactor pressure vessel, the main steam pipelines or the feedwater pipelines, leaked coolants and main steams flow out to the gap formed between the inner side of the outer wall and the outer side of the inner wall of the exterior of the double-walled structure, led through the transfer path and flow into pool water in the pressure suppression chamber. The elevation of the pressure in the dry wall is moderated since the leakage does not pass the dry well. With such a constitution, cost for the reactor container can be minimized, and pressure and the temperature inside can be reduced upon occurrence of an accident of leakage of coolants. (I.N.)