Start of Party Qualification Process for ITER Divertor

ITER components need to satisfy the highest quality standards. To guarantee this, a qualification process is foreseen for critical items, such as the plasma-facing components in the ITER divertor. A Party participating to the procurement package of such a component must demonstrate its technical capability through the successful and timely manufacturing of a medium-size “qualification prototype”.

The work to create these prototypes is covered by so-called “Task Agreements”, which is an agreement between ITER and a Party to do a certain amount of work or research. The Divertor Qualification Task Agreements have recently been signed by the European, Japanese and Russian Federation Participant Teams, and kick-off meetings with the EU and Russian Federation Participant Team have already taken place. The meeting with the Japanese Participant Team is scheduled early in July.

“After more than one year of negotiations to resolve all the technical and formal details, that’s an important step forward towards the procurement of the divertor”, said Mario Merola of the ITER Divertor Section, “and it’s equally important that it could start according to the planned time schedule”.

A Party is considered qualified if:

• It delivers at least two qualification prototypes, which meet all the prescribed acceptance criteria. The delivered prototypes can be manufactured via different technologies and/or different suppliers.
• At least one of the delivered prototypes withstands all the specified performance tests, which will be carried out in the high heat flux test facility located at the Efremov Institute in St. Petersburg, Russia.

Fig 1 (left): Vertical Target Qualification Prototype (procured by EU and Japan) Fig 2 (right): Dome Qualification Prototype (procured by Russian Federation)

The prototypes have a length of about 400 mm, and consist of three high heat flux units mounted onto an actively cooled fabricated supporting structure. They include all the most technically challenging features of the corresponding ITER design (Figs. 1 and 2).

The due date for the delivery of the prototypes is June 2008 and the completion of the high heat flux testing is planned by December 2008. This schedule should allow the divertor procurement packages to be delivered to the qualified Parties by February 2009 so that manufacturing can start in September 2009 as required by the present schedule.