Tool for retracting fuel rods from and inserting fuel rods into a nuclear fuel assembly and methods therefor
AssigneeGeneral Electric Company
InventorsWilliam C. Peters, David G. Smith, Edward G. Apple, Jr.
Life of this patent
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Abstract
The extraction tool includes an inner rod pivotally mounting at its distal end a pair of collet sections having mechanical clamping jaws. An outer tube may be advanced and retracted axially relative to the inner rod by a locking tube nut threaded on a sleeve forming part of the inner rod. The inner rod and outer tube are non-rotationally engaged with one another. By axially displacing the outer tube relative to the inner rod, the collet sections are movable between collet-open and closed positions such that the jaws of the collet can respectively grasp and release the barbed end of the end plug of the fuel rod.
Claims7
A method of extracting elongated fuel rods having end plugs terminating in end caps from a nuclear fuel assembly employing an extractor tool having an inner rod, an outer tube coaxially about and axially movable relative to said inner rod and a collet at an end of said tool having end cap engaging sections positively pivotable by a camming action about a pin carried by the inner rod between an open position spaced from the end cap and a closed position engaging about said end cap, comprising the steps of:
- (a) inserting said extractor tool into the fuel assembly with said collet sections in a closed position;
- (b) relatively displacing said inner rod and said tube in a first axial direction to positively cam and thereby pivot said collet sections about the pin into an open position;
- (c) advancing the extractor tool into the fuel assembly to enable the open collet sections to straddle said end cap;
- (d) relatively displacing said inner rod and said tube in a second opposite axial direction to positively cam and thereby pivot said collet sections about the pin into said closed position engaging about said end cap;
- and
- (e) jointly displacing said inner rod and said tube in an axial direction to withdraw the engaged fuel rod from said fuel assembly.
A method of inserting an elongated fuel rod having a first end plug terminating in an end cap into a nuclear fuel assembly employing an insertion tool having an inner rod, an outer tube coaxially about and axially movable relative to said inner rod and a collet at an end of said tool having end cap engaging sections positively pivotable by a camming action about a pin carried by the inner rod between an open position spaced from the end cap and a closed position engaging about said end cap, the fuel rod having a second end plug at an end thereof opposite said first end plug, comprising the steps of:
- (a) relatively displacing said inner rod and said tube in a first axial direction to positively cam and thereby pivot said collet sections about the pin into an open position
- (b) relatively displacing the tool and fuel rod to enable the open collet sections to straddle said end cap of said first end plug;
- (c) relatively displacing said inner rod and said tube in a second opposite axial direction to positively cam and thereby pivot said collet sections about the pin into said closed position engaging about said end cap;
- (d) inserting said tool and engaged fuel rod axially into the fuel assembly with said collet sections in said closed position about said end cap;
- and
- (e) inserting said second end plug into an opening in a tie plate of the fuel assembly.
Dependencies are inferred from the claim text.