Speaker
Paul Edwards
(Tokamak Engineering Department)
Description
The Final Design Review for the Blanket Manifold (BM) was successfully held in December 2015. Since the Conceptual Design Review, a concerted effort has been necessary on finalisation of the multi-pipe design, verification by analysis and practical validation to address challenging design requirements, and installation/maintenance processes.
During normal operating conditions the BM provide pressurised cooling water to the plasma facing Blanket System with a nominal inlet pressure and temperature of 4.0MPa and 70°C, respectively. The design complies with RCC-MR 2007 Construction Rules for Mechanical Components of Nuclear Installations -class 2.
The return circuits differ in temperatures by up to 40°C, which induce shear stress in neighbouring fixed pipe supports. The pipe to support interface has to accommodate conflicting requirements. On the one hand, it has to provide good thermal conductance in order to remove the neutronic heating. This would otherwise be conducted to the vacuum vessel (VV) attachment rails resulting in excessive thermal stresses. On the other hand, it has to be electrically insulated to mitigate excessive electromagnetic loads. For that purpose, a ceramic layer is used at each interface and VV attachment points.
Thermal expansion of the multi-pipe bundles due to the average increase of outlet water temperature is accommodated by compliant support attachment legs. RAMI analysis results in the majority of the BM classified as RH class3, necessitating conceptual maintenance studies to be undertaken. Customised design features for both initial installation and subsequent remote maintenance have been introduced to accommodate the as built mounting points and profile of the VV and other in-vessel components.
This paper provides details as to how the design has mitigated the conflicting requirements, the structural and EM verification of worst case operating scenarios, the practical validation to under pin design choices and the proven achievable build tolerances during the subassembly and installation processes.
Co-authors
Barbara Calcagno
(Tokamak Engineering Department, ITER, St Paul-lez-Durance, France)
Paul Edwards
(Tokamak Engineering Department, ITER, St Paul-lez-Durance, France)
Philippe Chappuis
(Tokamak Engineering Department, ITER, St Paul-lez-Durance, France)
Stefan Gicquel
(Tokamak Engineering Department, ITER, St Paul-lez-Durance, France)
