Liquid helium distribution system design for 10 MeV accelerator of C-ADS injector Ⅱ

The 10 MeV accelerator of C-ADS injector Ⅱ must be run under the liquid helium temperature, hence a helium distribution system has been designed according to the requirement of 10 MeV accelerator operating conditions. The system also has the function of regulating helium flow and providing liquid helium for vertical and horizontal testing of superconducting cavity and magnet test. The system has been applied to distribution and regulation of liquid helium for cryomodule of 5 MeV accelerator, as well as test of superconducting cavity, and it ran steadily. The paper focuses on the design of liquid helium distribution system, valve box structural design and debugging. (authors)