Remote maintenance of in-vessel components in Tokamak Fusion Test Reactor

The Tokamak Fusion Test Reactor (TFTR) will generate a total of 3 × 10²¹ neutrons during its planned D-T operational period. A maintenance manipulator has been designed and tested to minimize personnel radiation during in-vessel maintenance activities. Its functions include visual inspection, first-wall tile replacement, cleaning, diagnostics calibrations and leak detection. To meet these objectives, the TFTR maintenance manipulator is required to be operable in the TFTR high vacuum environment, typically < 1 × 10^-8 torr, (< 10^-6 Pa). Geometrically, the manipulator must extend 180° either direction around the torus to assure complete coverage of the vessel first-wall. The manipulator consists of a movable carriage assembly, a non-articulated link section mounted on the carriage, and six movable articulated link sections which are driven by electrical actuators. The boom has vertical load capacity of 455 kg and lateral load capacity of 46 kg. The boom can either be outfitted with a general inspection arm or dexterous slave arms. The general inspection arm is designed to hold the leak detector and an inspection camera; it is capable of rotation along two axes and has a linkage system which permits motion normal to the vacuum vessel wall. All systems except the dexterous slave arms are operable in a vacuum.