Reinforcement for a nuclear fuel assembly
AssigneeWestinghouse Electric Corp.
InventorsAlan Savinell, John D. Wood, Larry C. Montgomery, Ralph W. Tolino
Life of this patent
Estimating the term…
Abstract
A tie rod for reinforcing a nuclear fuel assembly. The tie rod includes an outer, hollow tubular member that extends from above the top nozzle through the bottom nozzle of the fuel assembly and has an axially split lower tip with an enlarged end and an upper portion having a circumferential threaded region. An inner rod extends axially through the hollow of the outer tube and has a slightly enlarged tip which spreads the split tip of the outer tube to lock the split tip below the lower nozzle of the fuel assembly. A nut is turned down on the upper threaded portion of the outer hollow tube and staked in position to lock the tie rod in position.
Claims15
A reinforcing member for a nuclear fuel assembly having a tube extending between a top nozzle and a bottom nozzle, comprising:
- a hollow tie rod having a threaded upper end and a flexible, compressible lower end, an outer surface and a length that will extend into and between the top nozzle and the bottom nozzle;
- an inner rod disposed within the hollow of the tie rod that will spread the flexible, compressible lower end when fully inserted;
- and
- a locking mechanism engaged with the tie rod outer surface and locked in place to prevent the locking mechanism from loosening when the locking mechanism is fully positioned.
A reinforced nuclear fuel assembly having a tube extending between a top nozzle and a bottom nozzle, comprising:
- a hollow tie rod having a threaded upper end and a flexible, compressible lower end, an outer surface and a length that will extend into and between the top nozzle and the bottom nozzle;
- an inner rod disposed within the hollow of the tie rod that will spread the flexible, compressible lower end when fully inserted;
- and
- a locking mechanism engaged with the tie rod outer surface and locked in place to prevent the locking mechanism from loosening when the locking mechanism is fully positioned.
A method of reinforcing a nuclear fuel assembly, having a tube extending between a top nozzle and a bottom nozzle, with a tie rod comprising the steps of:
- inserting a hollow tie rod assembly comprising a tie rod having an elongated axial dimension, threaded upper end, a flexible, compressible lower end and an outer surface and an axially moveable inner rod disposed within the hollow of the tie rod situated above the flexible, compressible lower end, the tie rod assembly being inserted through the top nozzle, through the tube that extends between the top nozzle and the bottom nozzle and through the bottom nozzle;
- driving the inner rod axially to the flexible, compressible lower end of the tie rod to expand the lower end of the tie rod below the bottom nozzle;
- pulling upwardly on the tie rod until the expanded lower end of the tie rod makes contact with a lower surface of the bottom nozzle;
- and
- engaging a locking mechanism with the tie rod outer surfaced just above an upper surface of the top nozzle.
Dependencies are inferred from the claim text.