Progress on the ITER TF Coil Winding Pack in EU

A principal part of the ITER fusion reactor is the Toroidal Field magnet system which consists of 18 “D” shaped coils. Fusion for Energy, (F4E), the European Domestic Agency for ITER, is responsible for the procurement of 10 such coils. The completed coils, measuring approximately 14 m × 9 m and weighing 300 tons, comprise an outer structural case into which a “winding pack”, itself made up of 7 conductor double pancake and radial plate assemblies, is inserted. The winding packs will be the largest ever built using Nb₃Sn conductor and their manufacture, using a wind, react and transfer process, presents significant technological challenges. In particular, the conductor double pancakes must be wound with high accuracy and their change in dimension during heat treatment correctly predicted in order to facilitate the transfer to their associated radial plates. These processes require novel and sophisticated tooling to be constructed on a large scale. The contract for the manufacture of 10 ITER TF Coil Winding pack was awarded in July 2010 by F4E to a consortium of three main partners-Iberdrola IC, ASG Superconductors and Elytt Energy and in this paper we present the progress made to date. Particular reference is made to the design and procurement of major items of tooling, including the winding line, heat treatment furnace and transfer tool, and the steps taken to minimize risk by design are described.