The background field coil, as an important part of
the CFETR superconductivity test platform, provides a constant magnetic field
environment for performance and stability testing of superconducting coils.
However, the background field coil is subject to multiple loads during
operation, such as gravity, preload, thermal, electromagnetic, etc. so its
integrity and stability must be ensured by the preload system. To verify the
reliability of the preload system under multi-load cases, based on the
homogenization theory, the mechanical properties of the preload system are
analyzed by simulation under four working conditions, namely independent
preload, integral assembly, integral cooling and coil excitation, and the
different types of stresses are evaluated by using the ASME standard. The
evaluation results show that the stress peaks of each preloaded component are
below the stress threshold and have sufficient safety margins, and the analysis
will provide theoretical references for the optimal design of the subsequent
background field coils as well as their processing and manufacturing.
