Nuclear reactor fuel element grid

Claim 1

A spacer member for holding nuclear fuel rods in spaced relation with their axes parallel, comprising a pair of substantially parallel and spaced-apart upper and lower grids formed from a plurality of intersecting metal strips so as to define a plurality of generally rectangular fuel rod cells, the cells of the two grids being aligned in pairs to allow a nuclear fuel rod to pass thorugh each pair and to retain the fuel rod within the aligned pair of cells, the metal strips being deformed to provide a plurality of stop members at least one of which protrudes into each of said cells to contact a fuel rod placed therein, means defining a plurality of bow springs at least one of which projects into each space that extends between each aligned pair of cells, said means comprising a plurality of elongate ladder-shaped members each having two parallel edge portions joined at intervals with transverse portions, said transverse portions forming said bow springs, one of said parallel edge portions of each of said ladder-shaped members being releasably connected to the upper parallel grid and the other edge portion being releasably connected to the lower grid, with the bow springs extending between upper and lower grids, each of said transverse portions being deformed as a bow spring to resiliently urge a fuel rod into engagement with the stop members, each ladder-shaped member extending in one direction across each grid structure and spanning a plurality of cells in each grid structure.