Abstract: An apparatus is provided for the automatic assembly of nuclear fuel rod bundles in a predetermined coordinate array. Each fuel rod is identified during its travel and positioned according to an identifying code carried on its lower end plug which designates the fuel enrichment and additive level of the rod.

Abstract: In a fuel assembly for a nuclear reactor a fuel element spacer formed of an array of laterally positioned cojoined tubular ferrules each providing a passage for one of the fuel elements, the elements being laterally supported in the ferrules between laterally oriented spring members and oppositely positioned rigid stops, the wall thickness of the ferrules being relatively large and the height of the ferrules being relatively small to reduce hydride concentration in the ferrule material while maintaining relatively low flow resistance.

Abstract: A spacer for use in a fuel assembly of a nuclear reactor having thin, full-height divider members, slender spring members and laterally oriented rigid stops and wherein the total amount of spacer material, the amount of high neutron cross section material, the projected area of the spacer structure and changes in cross section area of the spacer structure are minimized whereby neutron absorption by the spacer and coolant flow resistance through the spacer are minimized.

Abstract: In the processes of nuclear fuel manufacture, scrap material such as uncontaminated reject powder and reject pellets, which would previously have been reprocessed chemially in conversion of the uranium values by dissolution into liquid form, is now mechanically reduced by crushing in a substantially inert atmosphere and converted to a slurry having between about 70 to 85 weight per cent solids, and then attrition milled utilizing scrap sintered UO.sub.2 pellets as the reducing medium. Grinding swarf generated during the centerless grinding of UO.sub.2 pellets may also be recycled provided it is sufficiently pure.

Abstract: A storage module or rack is disclosed for storage of nuclear fuel assemblies in a water-filled pool comprising an array of storage tubes arranged in a checkerboard pattern and attached to one another along their corners. Each tube thus forms a storage cell for a fuel assembly and the spaces between each four adjacent tubes form intermediate fuel assembly storage cells. The storage tubes are formed with spaced double walls between which is contained a layer of neutron absorbing material to assure that the array of stored fuel assemblies remains subcritical. Provision is made for free circulation of water through the storage cells to extract heat from the stored assemblies. The storage module maximizes the number of fuel assemblies that can be stored in a given space while minimizing the material used in its construction.