Research on welding deformation of CFETR 1/16 vacuum vessel mockup

Abstract The 1/16 prototype sector of China Fusion Engineering Test Reactor (CFETR) vacuum vessel is being manufactured by Institute of plasma physics, Chinese academy of sciences (ASIPP). Welding deformation assessment and reduction are the major issues which need to be resolved since they will directly affect the overall contour of the vacuum vessel. In this paper, welding deformation finite element method (FEM) analysis of the 1/16 vacuum vessel was performed with ABAQUS based on the inherent strain theory. The welding shrinkage was compensated by reserving welding allowance, while the angular deformation was decreased by adding the restraints near the welds, as per analysis results. The welding deformation was finally measured by the laser tracker with fixed fiducial points distributed around the 1/16 vacuum vessel. The measurement results met the technical requirements and validated the FEM analysis, which can provide useful engineering instructions and guidelines for series production of vacuum vessel.