SPACER GRID DEVICE FOR A BEAM OF COMBUSTIBLE ELEMENTS OF A NUCLEAR REACTOR ASSEMBLY ASSEMBLY

摘要

A spacer grid assembly provides elastic support and secure positioning of fuel elements in a nuclear reactor. This spacer grid assembly comprises two families of thin perforated sheets, the sheets of one family being parallel to each other and perpendicular to the sheets of the other family. The interlaced assembly of these interfitting sheets forms a three-dimensional lattice of square-sectioned cells for positioning and securing the fuel elements vertically. This spacer grid assembly comprises large recesses within the cell walls that define the spring means. The spring means comprises two plates shaped as a flexible vault, a sheet stud connecting these plates, and two triangular strips integral with this sheet stud on one side and opposite each other on this same side, and ending in circular and protruding pads. These pads contact the fuel element and transmit the bearing power of the spring means to the fuel element. The fuel element is also in contact with rigid bosses on the face of the cell opposite the spring means. After the fuel element is fitted in the cell, the spring means move within the cell wall.