Kompaflex was commissioned by ITER to design, build and test a full scale prototype bellows that could withstand the extreme operating conditions of the tokamak fusion reactor.
The prototype large rectangular bellows measures 3.6 x 3.2 metres and is made of multiple thin layers of Inconel 625 alloy which can absorb dynamically the thermic expansion movements between the different structures and withstand the full vacuum.
The ITER bellows prototype was tested for helium leakage tightness, squirm, burst pressure test and spring rates. All results confirmed the parameters calculated during the design phase and required by the ITER specification.