Robotics take heat out of reactor

The Windscale prototype reactor is being decommissioned and dismantled. The stages are outlined. The first phase began in 1985 and included construction of a waste packaging plant annexed to the steel dome. The boilers will be cut up and, once decontaminated, probably sold for scrap. The second phase involves dismantling the reactor itself. Much of this will be done by a semi-automatic robot which is being specially built and tested. The robot will have an extendable arm with a manipulator which will be equipped with bolt croppers, shears, a saw and oxypropane cutter. This robot will cut up the pressure vessel in sections ready for encasing in concrete. Lessons learnt from the dismantling will be used in future reactor designs and specifications (eg the need to use steels with fewer impurities, especially cobalt). Ultimate disposal of the concrete waste blocks is undecided. (U.K.)