FIXTURE FOR RECTIFYING GUIDE-THIMBLE DAMAGE IN RECONSTITUTABLE NUCLEAR FUEL ASSEMBLY

摘要

The invention relates to a fixture (82) for rectifying different types of damage to upper end portions (44a-c) of guide thimbles (14a-c) of a reconstitutable fuel assembly (10) while the latter is being held in a work station (68) and has its top nozzle removed. The fixture comprises a base (84) having tool-positioning openings (90) arrayed the same as the guide thimbles (14) of the fuel assembly; means (92,70) for mounting the base on the work station (68) so that its tool-receiving openings are aligned with the guide-thimble upper end portions (44); and different kinds of tools (94,96,98) selectively mountable in the tool-positioning openings (90) of the base for operation thereof correcting the respective types of guide-thimble damage. The tools include a compressing socket (94) for reshaping outwardly bent guide-thimble end portions (44a); an expander tool (96) for reshaping inwardly bent guide-thimble end portions (44b); and a precision tube cutter (98) for severing irreparably damaged sections of guide-thimble end portions (44c). Any severed section is replaced with an adapter sleeve (136) rigidly connected to one, and slip-fit to the other, of the top nozzle and the shortened guide-thimble of the fuel assembly.