CLOSURE DEVICE FOR LIMITING THE CONVECTION CURRENTS IN AN ANNULAR SPACE AROUND A NUCLEAR REACTOR COMPONENT

摘要

The apparatus comprises an annular cup (5) solid with the component (1) and surrounding its outer wall, a frusto-conical support surface (9) having as axis the vertical axis (2) of the component (1) fixed at the perimeter of its large base to the passage (4) into which the component (1) passes and a closure element (14) with rotational symmetry. The closure element (14) has an upper part (15) which rests on the support surface (9) so as to totally close the annular space (18) at the top and a part directed downwards constituted by a sleeve whose lower part goes into the cup (5). The cup (5) fills up with liquid metal (17) which condenses when the reactor is operating, which ensures sealing between the sleeve (4) and the cup (5). The invention is particularly applicable to fast neutron nuclear reactors cooled by liquid sodium.