Guide tube retainer

In a reconstitutable fuel assembly having an upper end fitting with a plurality of bores therethrough each sized to receive a guide tube and at least one control rod guide tube with the guide tube including an upper end sleeve having a radially extending first shoulder at the lower end for engagement with the lower surface of said upper end fitting, an integral reusable locking arrangement between the guide tube and upper end fitting comprising:

• a. said upper end sleeve having a groove around the circumference adjacent the upper end of said sleeve;
• and
• b. said upper end fitting having a counterbore in each of said bores sized to receive a guide tube, the diameter of said counterbore being larger than the diameter of said bore so as to define a second shoulder therebetween;
• and
• c. a cylindrical tube concentric with said sleeve, said cylindrical tube having a plurality of flexible tabs extending outwardly and circumferentially spaced apart around the lower end and substantially at the mid section of said tube such that the tabs at the mid section of said tube are received in the counterbore in the upper end fitting and for engagement with said second shoulder, a plurality of flexible tabs extending inwardly and upwardly and circumferentially spaced apart adjacent the upper end of said tube whereby said inwardly facing tabs are sized to be received in the groove around said sleeve, the lower end surface of said tube being engaged with said first shoulder.