摘要:
A pressure vessel includes upper and lower vessel sections joined by a flanged connection. A nuclear reactor core includes an array of fuel assemblies comprising fissile material. The nuclear reactor core is disposed in the lower vessel section. A side-entry vessel penetration is located at a side of the pressure vessel and passes through one of (i) a flange of the flanged connection and (ii) the lower vessel section. An incore instrument routing tube extends from the side-entry vessel penetration and enters the reactor core from above the reactor core. The incore instrument routing tube extends from the side-entry vessel penetration with a declination angle A E and includes a 90°-A E downward turn to enter the reactor core from above. The declination angle A E may be zero so that the routing tube extends horizontally from the side-entry vessel penetration and includes a 90° downward turn.
摘要:
A nuclear reactor core is disposed in a pressure vessel along with upper internals disposed in the pressure vessel above the reactor core. The upper internals include internal control rod drive mechanisms (CRDMs) mounted on a suspended support assembly. A hollow cylindrical central riser is disposed in the pressure vessel above the nuclear reactor core. A hollow cylindrical section is disposed in the pressure vessel below the hollow cylindrical central riser and surrounding the nuclear reactor core. A riser transition element connects with the hollow cylindrical central riser and the hollow cylindrical section to form a continuous hollow cylindrical flow separator. The suspended support assembly of the upper internals is suspended from the riser transition element. The pressure vessel may comprise upper and lower vessel sections connected by a mid-flange, with the riser transition element welded to the mid-flange by gussets extending outward and upward from the riser transition element to the mid-flange.
摘要:
A riser cone has a lower end sized to engage a cylindrical lower riser section of a nuclear reactor and an upper end sized to engage a cylindrical upper riser section of the nuclear reactor. The riser cone defines a compression sealing ring that is compressed between the lower riser section and the upper riser section in the assembled nuclear reactor. In some embodiments the riser cone comprises: a lower element defining the lower end of the riser cone; an upper element defining the upper end of the riser cone; and a compliance spring compressed between the lower element and the upper element. In some embodiments the riser cone comprises a frustoconical compression sealing ring accommodating a reduced diameter of the upper riser section as compared with the diameter of the lower riser section.