Development of Divertor Remote Maintenance System
Nobukazu Takeda, Kiyoshi Oka, Kentaro Akou and Yuji Takiguchi
Naka Fusion Research Establishment, Japan Atomic Energy Research Institute, 2-4 Shirakata-shirane, Tokai-mura, Naka-gun, Ibaraki 319-1195, Japan
The ITER divertor is categorized as a scheduled maintenance component because of extreme heat and particle loads it is exposed to by plasma. It is also highly activated by 14 MeV neutrons. Reliable remote handling equipment and tools are required for divertor maintenance under intense gamma radiation. To facilitate remote maintenance, the divertor is segmented into 60 cassettes, and each cassette weighing about 25 tons and maintained and replaced through four maintenance ports each 90 degrees. divertor cassettes must be transported toroidally and radially for replacement through maintenance ports. Remote handling involving cassette movers and carriers for toroidal and radial transport has been developed. Under the ITER R&D program, technology critical to divertor cassette maintenance is being developed jointly by Japan, E.U., and U.5. home teams. This paper summarizes divertor remote maintenance design and the status of technology development by the Japan Home Team.