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The ITER thermal shield is actively cooled by 80 K pressurized helium gas. The helium coolant flows from the cold valve box to the cooling tubes on the TS panels via manifold piping. This paper describes the final design of thermal shield manifold. Pipe design to accommodate the thermal contraction considering interface with adjacent components and detailed design of support structure are presented. R&D for the pipe branch connection is carried out to find a feasible manufacturing method. Global structural behavior and structural integrity of the manifold including pipe supports are investigated by a finite element analysis based on ASME B31.3 code. Flow analyses are performed to check the flow distribution.

The final design of ITER vacuum vessel thermal shield (VVTS), which is planned to be procured completely by Korea, has been implemented after the procurement arrangement was signed. In this paper, the design and the supporting analysis are described for the key components of the VVTS such as joint, panel, support, and stopper. The VVTS design is revised and finalized based on the manufacturing feasibility, interface requirement and assemble feasibility. The inboard and the outboard supports of VVTS are designed in detail considering structural rigidity and assemble feasibility. The shape of in-pit joint, which is installed every 40° sector in toroidal direction for compensation of possible misalignment during sector assembly, is determined. Three types of joints are developed in accordance with their locations and assemble feasibilities are checked through the R&D. Stopper design is developed in order to prevent direct contact against adjacent components such as vacuum vessel and magnets. Structural rigidity of the whole VVTS is also validated by finite element analysis under various kinds of operating conditions, such as deadweight, electro-magnetic load, seismic load and load combinations.