Process and installation for welding grids for nuclear fuel assemblies

摘要

For welding a grid formed by sets of plates disposed orthogonally and whose endmost parts are secured to a surround, it is placed in a shaping and mechanically holding frame allowing access to the point to be welded. The frame containing the grid is then placed on a revolving device belonging to a roundabout, at a first welding position and welding is carried out therein on at least one face of the grid by means of a welding member movable in two perpendicular directions for bringing it at right angles to each of the welding points on the face. The frame is then brought to a second welding position in which the plates are welded to the surround by means of a second welding member movable in only one direction, after rotation through 90 DEG of the frame by means of the revolving device; and the operations are repeated as necessary until the whole of the welds have been executed.