| 摘要 |
<p>The invention relates generally to a reconstitutable nuclear fuel assembly and, more particularly, to improved means for maintaining releaseble locking engagement between upper guide-thimble extensions and sockets in the adapter plate of the top nozzle of the fuel assembly.
<??>The improved means associated with each guide thimble comprises a locking tube (48) with a radial protuberance (80) on a lower portion thereof, and two circumferential bulges (76, 78) formed on the guide-thimble extension (44) and cooperable with the protuberance (80) on the locking tube to retain the latter in either a locking position for preventing release of the guide-thimble extension from the associated socket (50) in the adapter plate (40), or an unlocking position permitting release of the guide-thimble extension from the socket.
<??>As distinct from previous arrangements providing for withdrawal of the locking tubes from the guide-thimble extensions, the present arrangement provides for the locking tubes to be pushed farther into, and retained in, the associated guide-thimble extensions during removal of the top nozzle. </p> |
