Patent Number: 044850689
Section: claims

1. An installation for the storage of nuclear fuel assemblies, wherein it comprises a storage enclosure having side walls and adapted to contain nuclear fuel assemblies therebetween, at least one station for loading and unloading said nuclear fuel assemblies from above said side walls by lowering and raising said nuclear fuel assemblies, and a plurality of storage station, each station for loading and unloading and each of said storage stations being located in said enclosure, modules each of which receives nuclear fuel assemblies, each of these modules being located in one of the stations, the number of modules being less than that of the stations, lifting means for creating a fluid cushion below at least some of the modules in order to raise the latter within the enclosure and means for moving the modules between the different stations when they are raised by the lifting means, lateral rollers located on each module to cooperate with the adjacent modules. 2. An installation according to claim 1, wherein the loading and storage stations are aligned in rows in two different directions, the lifting means act independently in each of the rows and the means for displacing the modules act simultaneously on all the modules of the same row. 3. An installation according to claim 2, wherein the loading and storage stations are aligned in rows in two orthogonal directions, the storage enclosure then being rectangular and the modules square. 4. An installation according to claim 2, wherein means are provided for guiding the modules during their displacements between the different stations. 5. An installation according to claim 4, wherein the module guidance means comprises guide rails positioned on the periphery of the storage enclosure and between certain of the said rows, except the ends of the rows, and lateral rollers located on each module to cooperate with the guide rails. 6. An installation according to claim 5, wherein each module is equipped with four rollers positioned at the four corners of the square which it defines in cross-section, two of the rollers adjacent to the same side of the square being located in a horizontal plane displaced with respect to the two other rollers. 7. An installation according to claim 1, wherein the means for displacing the modules are constituted by jacks positioned outside of the enclosure at least at one end of at least one part of the said rows. 8. An installation according to claim 1, wherein the lifting means comprise parallel pipes positioned level with the floor or base of the enclosure and comprising uniformly distributed lifting nozzles, the pipes being supplied with a pressurized fluid. 9. An installation according to claim 5, wherein it also comprises a cooled fluid circuit. 10. An installation according to claim 9, wherein each module comprises an upper plate, means for supporting the fuel assemblies, a lower plate whose lower face is flat so as to permit the raising of the module by lifting means and an intermediate ferrule surrounding the fuel assemblies and defining the vicinity of each of the plates a passage enabling the cooled fluid to circulate in the ferrule. 11. An installation according to claim 10, wherein the rollers are carried by the lower plate. 12. An installation according to claims 10 or 11, wherein the means for supporting the fuel assemblies comprise a drop or fall absorber system for each of the assemblies. 13. An installation according to claim 10, wherein the upper plate is centrally provided with gripping means permitting the manipulation of the module via a trapdoor located in the top or ceiling of the enclosure at the loading and unloading station. 14. An installation according to claim 10, wherein the intermediate ferrule carries interconnected bars preventing swinging or rocking of the fuel assemblies. 15. An installation according to claim 10, wherein the lower plate has edges defining a reservoir on its upper face.