Development of in-vessel pipe alignment tool for ITER blanket remote maintenance

Highlights: • A prototype of pipe alignment tool for ITER First Wall cooling pipe welding operation was designed and fabricated. • Allowable misalignment for cooling pipe was estimated as 1.5 mm in lateral misalignment and 0.25° in angular misalignment. • Testing suggests 1.5 mm in lateral misalignment and 0.5° angular misalignment can be corrected by in-bore pipe alignment. - Abstract: ITER blanket modules must be handled remotely because the radiation levels inside the vacuum vessel after DT experiments will be too high to allow for hands-on access to the in-vessel components. Remote tools for cutting, welding, and weld inspection of hydraulic pipes within the blanket modules are necessary. We designed an in-bore pipe alignment tool that can be integrated with other laser welding and weld groove observation tools because the pipe weld grooves must be aligned with the utmost precision when welding remotely to ensure a good quality weld. This paper presents the development of the pipe alignment tool, including FEM analysis and mock-up testing to define the specification of the pipe alignment tool and to confirm the in-bore pipe alignment concept.