| 摘要 |
Case 2989 APPARATUS FOR DEFUELLING A NUCLEAR REACTOR A defuelling arrangement for removing fuel bundles from the upstream end of a nuclear reactor, has a defuelling machine at the upstream end with an arm that can be positioned in axial alignment with a fuel channel in the reactor which has fuel bundles to be removed. The arm is capable of axial movement. A fuel grapple is positioned in alignment with the arm and has at one end a plurality of fingers for grappling a fuel bundle and at the other end a mushroom shaped spigot. The arm has mounted on the end a defuelling ram head which has at least two ram head latches mounted for pivotal movement in a plane at right angles to the axis of the arm. Each latch has a inner latching end and a releasing end, and is spring biased to move the latching end towards the axis. The latching end has a sloping edge which engages the end of the mushroom spigot when the arm is advanced to pass the latches against the spigot. The latches pivot to move the latching ends outwardly over the mushroom end of the spigot and then spring outwardly behind the mushroom end to couple the grapple to the ram head. The arm can now be advanced to grapple the end of a fuel bundle and withdraw it. |
