Control rod canopy seal positioning and welding system

摘要

A system is directed for remotely securing a canopy seal about a broken omega seal site between the control drive mechanism and the adapter tube of a nuclear reactor vessel so as to contain any radioactive leakage therebetween. The system includes a stalk measuring device for initially measuring the diameter of the adapter tube, a split canopy installation fixture which is adjusted according to the measurement detected by the stalk measuring device to position a two-piece canopy seal about the omega seal site, and a robotic weld arm for performing the upper and lower radial welds about the canopy seal as well as C-shaped vertical welds between the two-piece canopy seal.