ITER vacuum vessel sector manufacturing development in Europe

The ITER vacuum vessel, to be constructed on site from nine toroidal sectors, places as-welded manufacturing tolerances on the surfaces several times smaller than usual, in relation to its large size. Framatome ANP has proposed a manufacturing route for the sector construction, accepted as the reference by the ITER International Team. To facilitate the achievement of the required tight tolerances, EFDA has implemented a development programme, including the manufacturing part of the sector and the analysis of its distortion using SYSWELD computer modelling. This paper describes the manufacturing route and the results of the development programme so far.