F. Elio

Design Improvements and R&D Achievements for Vacuum Vessel and in-Vessel Components Towards ITER Construction

During the preparation of the procurement specifications of ITER for long lead-time items, several detailed vacuum vessel (VV) design improvements are being pursued, such as elimination of the inboard triangular support, adding a separate interspace between inner and outer shells for independent leak detection of field joints, and revising the VV support system to gain more structural performance margin. Improvements to the blanket design are also under investigation, an inter-modular key instead of two prismatic keys and a co-axial inlet?outlet cooling connection instead of two parallel pipes. One of the most important achievements in the VV R&D has been demonstration of the necessary assembly tolerances. Further development of cutting, welding and non-destructive tests for the VV has been continued, and thermal and hydraulic tests have been performed to simulate the VV cooling conditions. In FW/blanket and divertor, full-scale prototypical mock-ups of the FW panel, the blanket shield block, and the divertor components, have been successfully fabricated. These results make us confident in the validity of our design and give us possibilities of alternate fabrication methods.

Design and R&D progress of blanket attachments

The ITER blanket is built of small regular modules attached to the vacuum vessel by an insulated mechanical support system, an electrical connector for grounding and a hydraulic connector for the coolant manifolds. An attachment has been developed which satisfies the demanding load conditions and which includes the handling features to enable the removal of the module for repair in the hot cells. Latest improvements are presented with the comprehensive R&D activities used to validate the design.