Investigation of the characteristics of zircaloy-4 endplate welds for a fuel bundle fabrication

This study was focused on the establishment of the remote resistance welding technology for the hot cell environment for a DUPIC (Direct Use of spent PWR fuel In CANDU reactors) fuel fabrication. To do this, a preliminary investigation for a hands-on fuel fabrication outside a hot cell was conducted with a consideration of the constraints caused by welding in a hot cell. Further welding experiments were carried out to improve the RW process. A remote resistance welding apparatus was developed. The characteristics of the welds made by RW and LBW were compared in terms of their weld nugget penetration and torque strength. It was found that the resistance welding process was a more suitable welding process for joining the endplate to the end caps in the hot cell. The optimum conditions for RW in the hot cell operation in a remote manner were also obtained. (author)