The Blanket Module Project (L- 4)

The objectives of the blanket module project are:

• to assess the manufacturing feasibility by developing and fabricating prototype components for the shielding blanket
• to assemble modules together and develop bolting, welding and cutting tools for the remote removal of the components
• to demonstrate the performance by testing representative parts of the components under relevant conditions
• to obtain confirmation of the design choices through results from accompanying R & D on materials, joining techniques and neutronics using a fast neutron source

Figure 1:Front side view of the Shield
Prototyp fabricated by powder HIPping
(Powdermet/Sweden)

The European Home Team has lead responsibility for implementing the project.

In view of the fact that the shield blanket module represents a novel component for a fusion device, its development has been very successful. Modern technologies have been adopted and further developed to suit the requirements of the module, and in particular the First Wall manufacture.
Performance tests have demonstrated that these technologies provide comfortable margins against the expected operational loads and should thus provide sufficient reliability and enough flexibility to cope with potential operational uncertainties. Prototypical components have been manufactured on the basis of specifications which were more complex than required by the new ITER design, and hence provide full confidence in the manufacturing feasibility. Key engineering issues have been addressed and resolved. This confirms, together with the results from other complementary activities, that the shield blanket can be properly integrated into the ITER device.
Further developments are underway to qualify new and more cost effective solutions.

EU Shield Block Prototype

Figure 2:Rear Side view of the Shield
Prototyp fabricated by powder HIPping
(Powdermet/Sweden)

The Shield Prototype fabricated by the European Home Team was representative of the Primary Wall Module No. 11 as designed for the ITER 1998 Design. This module was selected because of its double curvature in poloidal and toroidal directions. It consists of a 316LN Stainless Steel block of about 4 tons, equipped with eight penetration holes through it and with all the features at the rear and side walls required for the module attachment system. All these requirements led to a complex cooling channel arrangement inside the module, making the fabrication by powder Hot Isostatic Pressing (HIPping) cost effective. Considering also the good mechanical properties of powder HIPped 316LN stainless steel obtained from the material development programme, powder HIPping showed to be a competitive alternative fabrication method for the manufacture of the Shield of ITER Primary Wall Modules.

EU Primary First Wall Panels

The extensive R&D programme implemented in Europe in the frame of the ITER Blanket Project has allowed developing and selecting the materials and the fabrication methods for manufacturing the Primary First Wall Panels for ITER. Joining of the Cu alloy heat sink material (DS-Cu or PH-Cu) onto 316LN stainless steel is done by HIPping and Beryllium tiles are joined onto the Cu alloy by HIPping or brazing. HIPped Primary First Wall mock-ups achieved 13,000 cycles at 0.7 MW/m² and 1000 cycles at 2.5 MW/m². Thermal fatigue testing of brazed mock-ups is still in progress.
The manufacture of Primary First Wall Panel prototypes with brazed and HIPped beryllium tiles will be completed in June 2001. After completion, they will be thermal fatigue tested at 0.8 MW/m².

Figure 3:Be/DS-Cu/SS mock-up fabricated
by CEA (F) and tested at Jülich (D) for
1000 cycles at 2.5 MW/m2

Figure 4:Be/DS-Cu/SS mock-up fabricated by Framatome (F)
and tested at JRC Ispra (I)
for 13,000 cycles at 0,7 MW/m2