Mobile tele-operator for removing a contaminated junction box

摘要

At the Savannah River Plant a leak of radioactive liquid in an equipment corridor had contaminated the inside of a junction box to a level of 200 R measured at the exterior surface. The box would have to be removed to allow normal maintenance and repair of equipment in this section of the corridor. It was estimated that a total exposure of 8 R would be required to remove the box manually, even with tools mounted on long poles. The Robotics group at the Savannah River Laboratory was asked to develop a method to remotely remove this junction box. The Robotics group, with assistance from the Interim Waste group, obtained a hydraulic cutter that was capable of making the 13 cuts required to remove the box. The cutter blades were of a special design that could cut through the 2-inch conduit with minimum force. A Pedsco mobile tele-operator was extensively modified to manipulate the cutter. A new upper arm assembly in the elbow-up configuration was installed, a tool-mounted camera was installed, and two additional degrees of freedom were added: a wrist rotate and a wrist pitch. The cutter attachment was designed to allow the cutter to be placed in threemore » different orientations on the wrist, so that it could make all the cuts. 1 ref., 6 figs.« less