Manufacturing of JT-60SA Cryostat Base

JT-60SA is a superconducting tokamak to be assembled and operated at the JAEA laboratories in Naka (Japan) [1]. The tokamak has been designed to prepare, support and complement the ITER experimental programme and will be manufactured and operated under the funding of the Broader Approach Agreement (between the government of Japan and the European Commission) and of the Japan Fusion National Programme. Within the European contribution to JT-60SA, Spain has to provide the cryostat. Due to functional purposes, the cryostat has been divided in two large assemblies: the Cryostat Base (CB) and the Cryostat Vessel Body the latter subdivided into Cryostat Vessel Body Cylindrical Section (CVBCS) and the Top Lid. Spain is committed to provide the design and subsequent manufacturing of the CB and CVBCS (excluding the Top Lid) through the National Laboratory of Fusion at Ciemat. The design of both components has been concluded and the CB is currently being manufactured by a Spanish company, IDESA. This paper aims to present the status of the manufacturing and pre-assembly at the factory of the CB that has to be delivered in November 2012.

► JT-60SA Cryostat Base has been fabricated in seven structures fastened by bolts.
► The pieces are fully welded structures further machined to get required tolerances.
► The pre-assembly of the Cryostat Base will be done at the factory to check final tolerances as well as to anticipate problems which could be encountered during final assembly.