Patent Number: 050948032
Section: claims

1. A steam generator utilized for a liquid-metal coolant reactor comprising: an outer body shell of hollow cylindrical structure provided with a water inlet chamber disposed at a lower portion of the body shell, an outlet steam chamber disposed at an intermediate portion of the body shell, and a liquid metal inlet portion disposed at an upper portion of the body shell;  a heat transfer tube arranged in an annular space formed by an inner wall of the body shell so as to connect said water inlet chamber and said outlet steam chamber;  a liquid metal outlet rising pipe axially extending along substantially a central portion of said body shell and  an electromagnetic pump arranged at an upper portion inside said liquid metal outlet rising pipe;  said electromagnetic pump comprising a hollow cylindrical iron core provided with a comb-shaped portion at an outer peripheral surface thereof and an annular stator coil assembled in the comb-shaped portion of the cylindrical iron core, a main passage of liquid metal being formed on a side on which said stator coil of the iron core is assembled, a cooling bypass passage being formed at substantially the central portion of said cylindrical iron core in a vertically penetrating fashion; and  wherein said cylindrical iron core comprises an inner iron core portion and an outer iron core portion disposed proximate an outer peripheral surface of said inner iron core portion with a concentric space formed therebetween and said coil is assembled in an outer peripheral surface of said inner iron core portion and in an inner peripheral surface of said outer iron core portion. 2. A steam generator according to claim 1, further comprising additional cooling bypass passages formed at a central portion of said inner iron core portion and on an outer peripheral side of said outer iron core portion. 3. A steam generator according to claim 1, further comprising a reaction pressure suppressing cylinder disposed outside of said outlet rising pipe concentrically therewith with a space formed therebetween for the communication of liquid metal, and a reaction pressure releasing pipe arranged in association with said reaction pressure suppressing cylinder.