Liquid metal storage tank

The present invention concerns a liquid metal storage tank used for an FBR type reactor plant. It comprises a tank main body disposed in a pit chamber, a sealing tub disposed at an upper outer circumferential surface of the tank main body, a roof portion which closes the opening a the upper end of the pit chamber, a sealing partitioning cylinder suspended from the lower surface of the roof and having its lower end extended to the inside of the tub and a sealing liquid metal filled in the tub. The tank main body is kept at a high temperature by the liquid metal while the roof in the upper portion of the pit chamber is kept at a low temperature. Further, since the tank main body and the inside of the pit chamber are sealed by the sealing partitioning cylinder, no large thermal stresses are caused to the wall of the tank main body. Even if hydrogen gases are generated in the tank main body, since they can be released to the inside of the pit chamber, the integrity of the tank can be maintained, even if abrupt pressure elevation is caused in the tank main body. (I.S.)