A METHOD OF SECURING A TUBE IN A BORE THROUGH A SPHERICAL WALL, AND A DEVICE FOR DEPOSITING WELDING MATERIAL IN A FACING

摘要

Fixing a cylindrical tube (3) passing through a bore (5) in a spherical wall (4) of a nuclear pressurized water reactor cover comprises machining an annular recess (7) in the inner surface of the cover round the bore and filling it with two layers of metal (8, 12) to which the tube is welded. The metal layers are deposited by an automatic welding torch (20) with a continuous metal feed (23) and fusion unit (20') that is rotated about the axis (10) of the bore and moved in a direction (Z) parallel to it, so that the metal is deposited in the form of a bead with constant characteristics. The first layer of metal is deposited as the torch rotates on a shaft inserted into the cover, while the second is applied after fitting the tube and with the torch shaft rotating inside it.