| 摘要 |
A tool for protecting a boiling water reactor component against damage by a shroud repair assembly suspended from a cable and lowered into the downcomer annulus. The tool has a roller with an outer surface made of a material which will not scratch the surface of a tie rod of the shroud repair assembly as the latter is lowered relative to the roller. The tool has sets of opposing grippers made of aluminum alloy which are pressed against opposing surfaces of the shroud and the reactor pressure vessel with sufficient force to clamp the tool in the annulus. The pressing force is generated by air-actuated cylinders which are actuated remotely. In one embodiment, the roller is fixed and acts as a stop to limit tangential travel of the suspended assembly. In another embodiment, the roller is displaceable in a tangential direction in response to remote actuation of a pair of air-actuated positioning cylinders. The roller is displaced to push the contacting portion of the shroud repair assembly in a tangential direction, e.g., to a position where the suspended assembly will avoid a reactor component upon further lowering of the assembly.
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