Cryogenic mechanical testing of ITER prototype axial breaks

Within the superconducting magnet program for ITER, cryogenic components need to be tested to verify their design. Especially for the helium supply of the magnet system, feeders are needed integrating at the same time high voltage insulation to separate the inner magnet system electrically from the outer cryostat shell. Beside of high voltage and helium flow properties, these axial breaks will be exposed to a limited mechanical loading during operation of the magnet system. Therefore, mechanical tests needs to be performed at room temperature as well as at cryogenic temperature of 77 K.A possible breaker design was provided by Babcock Noell. To verify this design mechanically quasi-static and fatigue tests under bending, torsion and axial loading were done. Results on the performance of the prototypes are presented approving a superior mechanical quality.