Remote handling tools for hydraulic connections of divertor cassettes in JT-60SA

摘要

Two types of alignment tools has been developed for hydraulic connection between cooling pipes in divertor cassette and vacuum vessel in JT-60SA. These tools were designed to be used by a remote handling system that are planned for the maintenance and repair of the divertor cassette in the latter research phase of JT-60SA. Plasma facing components on the divertor cassette will be actively cooled because they are exposed to high heat flux. Before connecting two cooling pipes by a laser welding tool, an alignment of the groove is required. Here, the outer diameter, thickness and material of the cooling pipe are 59.8 mm, 2.8 mm and SUS316 L, respectively. The axial misalignment at the groove position is predicted to be 3 mm as the maximum owing to the installation accuracy of the pipes in the vacuum vessel. The axial misalignments were successfully aligned less than the welding range of < 0.5 mm by these alignment tools. These alignments were achieved by a simple z-motion by bolting that were to be applicable to a remote handling tool.