Manufacture of the vacuum vessels and the ports of Wendelstein 7-X

In the Wendelstein 7-X (W7-X) stellarator, the superconducting magnet system is enclosed between two toroidal vacuum vessels, which function also as the inner and outer wall of the cryostat system. Several ports joining both vessels connect the plasma chamber with the auxiliary systems, provide a suitable access for maintenance and servicing the in-vessel components, and are used for the heating systems, the diagnostics and vacuum pumping. The manufacture of the plasma vessel (PV), the outer vessel (OV) and the ports is presently well in progress. The first components have already been delivered on site and are being prepared for the final assembly. This paper describes the manufacturing processes adopted and the problems encountered.