Abstract: An anti-earthquake support device arranged between an element of large mass and a fixed support, comprising roller elements arranged between support parts forming roller tracks inclined with respect to the horizontal plane. The roller elements are cylindrical rollers (14,15,17) arranged horizontally in two superposed sets of rollers with perpendicular axes. The support parts (4,10 and 11) are entirely independent of one another and are arranged above one of the sets of roller for the first (4), between the two sets of rollers for the second (10) and beneath the second set of rollers for the third (11). The corresponding roller tracks (9, 20, 21 and 24) are formed on either the lower, or the lower and upper, or the upper surfaces of the three support parts (4, 10 and 11), respectively. The invention is used for the support of a fuel assembly rack for a nuclear reactor on the bottom of the storage pool of such reactor.

Abstract: A nuclear reactor containing assemblies having two caps and a framework inside which fuel rods are disposed vertically is reloaded by first inverting the assembly to be removed into a vertical position permitting the then lower cap to be demounted. The spent fuel rods are then identified and removed in sets and deposited in a suitable storage area, and replacement rods are placed in sets in the framework of the fuel assembly. Finally, the lower cap is replaced and the assembly is conveyed into the reactor vessel at its new location.

Abstract: Apparatus for charging a nuclear reactor disposed at the bottom of a pool. The reactor is constituted by a plurality of tiers of combustible assemblies having different stages of enrichment, each assembly having combustible rods and an auxiliary cluster associated with the particular tier of the assembly. The apparatus comprises a rolling bridge supported for movement in a plane above the pool, and carrying a turnable platform which supports a plurality of vertical telescopic manipulation arms arranged in angular spaced relation thereon. Each arm carries a respective grappling unit for respectively engaging a complete combustible assembly or at least one type of auxiliary cluster. The auxiliary clusters may include control clusters, sealing clusters and poison consumable clusters.