Plasma and Fusion Research

Volume 14, 3405062 (2019)

Regular Articles

Study on Butt Weld Joint of Thick Plate Superconducting Coil Structure to Reduce Welding Residual Deformation
National Institute for Fusion Science, Toki 509-5292, Japan
(Received 27 December 2018 / Accepted 23 February 2019 / Published 10 April 2019)


In a large fusion experimental device, the magnetic field in the coil is rather high to create higher magnetic field at the plasma center, and the coil current is very large resulting in generation of huge electromagnetic force. To sustain such huge electromagnetic force, thick section components are required for the coil structure of which material is generally an austenitic stainless steel to avoid magnetization. On the process of the welding design, the welding residual deformation must be taken into account to keep the position of the current center of the coil and to avoid the degradation of the superconducting conductor by the excessive welding residual strain. In this paper, a partial welding which was used for the LHD construction will be focused and the image of the conceptual welding design of ITER TF coil butt joints will be discussed for an example of the fusion application.


partial welding, welding residual stress, welding residual deformation, LHD, ITER, TF coil

DOI: 10.1585/pfr.14.3405062


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