量研学術機関リポジトリ「QST-Repository」は、国立研究開発法人 量子科学技術研究開発機構に所属する職員等が生み出した学術成果（学会誌発表論文、学会発表、研究開発報告書、特許等）を集積しインターネット上で広く公開するサービスです。 Welcome to QST-Repository where we accumulates and discloses the academic research results(Journal Publications, Conference presentation, Research and Development Report, Patent, etc.) of the members of National Institutes for Quantum and Radiological Science and Technology.
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The JT-60SA Tokamak is provided with a cryogenic system with a refrigeration capacity of 9 kW (eqv.) at 4.5 K. Before commissioning and during occasional warm-up periods the total 3.6 t helium inventory (at ∼1.5 Mpa(g)) is stored in six pressure vessels. Each vessel is 22 m long, has a diameter of 4 m, 250 m3 volume, and weighs about 73 t. As the vessels will store pure helium, the tightness and cleanliness require- ments were quite demanding. One of the vessels is also used to receive the cold helium (20 K) from the cryogenic system quench line, following a fast discharge of the superconducting coils. A special 18 m long helium diffuser system and a thermal barrier connector at the quench line flange have been designed and manufactured to avoid local chilling of the vessel wall below the minimum allowed temperature of the material.
Manufacturing and installation of the JT-60SA helium storage vessels for the cryogenic plant
