Reactor vessel and method of mounting a nozzle of such reactor vessel

摘要

To facilitate mounting of a nozzle, is provided a nozzle mounting structure for mounting a nozzle (20) penetrating through a reactor vessel (10) having a hemispherical concave inner surface, the nozzle mounting structure includes a removed concave portion (17) in which a base material (12) on an inner surface side of the reactor vessel (10) is removed in a symmetrical shape around a normal line (N) on the hemispherical concave inner surface of the reactor vessel (10), a flange (25) provided on the nozzle (20), formed in a same symmetrical shape as that of the removed concave portion (17) around the normal line (N), and inserted into the removed concave portion (17), and a weld part (18) provided around the normal line (N) for welding the flange (25) to the reactor vessel (10).