Locking tube removal and replacement tool and method in a reconstitutable fuel assembly

摘要

A tool for removing a locking tube from a locking position in the upper end portion of a guide thimble inserted within a passageway in a removable top nozzle of a reconstitutable fuel assembly includes an inner tubular member attached at its upper end to a bail assembly and at its lower end to a tubular extension having an expandable and collapsable lower end. Also, an actuatable shaft assembly of the tool is mounted for axial movement within the inner tubular member and lower tubular extension and has a conical nose disposed on its lower end which extends beyond a rim formed on the lower end of the tubular extension and an actuating knob coupled to its upper end. Rotation of the knob in one direction causes insertion of the conical nose into the lower end of the tubular extension and thereby increase in the circumference of the rim such that it will engage a lower edge of the locking tube when the tool is forced in an upward direction. An outer tubular member of the tool is disposed about the inner member and mounted for slidable movement therealong. The outer tubular member is manually moved in a reciprocating manner to deliver a series of forceful impacts to the bail assembly of the tool which impacts are, in turn, transmitted via the inner member to the lower end of the tubular extension. When the latter is expanded into engagement with the lower edge of the locking tube, the force of each impact will displace the locking tube in an upward axial direction to remove the tube from its locking position.