The Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP) has developed a large-scale vacuum electron beam welding (EBW) system, including China Fusion Engineering Test Reactor (CFETR) vacuum vessel collar as a pre-research part completed by this system, and it has passed the expert acceptance test recently.
The acceleration voltage of the system is 150kV, with the rated power 60kW, and the volume of the vacuum vessel is 66.5m3. The pre-research collar composed of Austenitic stainless steel 316L is about 4.2m multiply by 2.7m in dimension, and contains different welding thickness, 50mm, 60mm, and from 50mm to 160mm variable cross-section welding line.
With the intact surface after welding, the welding quality meets EN ISO 13919-1: 1996 Quality Level B Standard.
The completion of the EBW system and the breakthrough of welding technology of CFETR vacuum vessel collar demonstrate the ability of ASIPP in electron beam welding of large welding components, which lays the technical foundation for the future collar welding in CFETR vacuum vessel, and provides a solution for welding new, refractory and dissimilar materials used in CFETR.