Welding metal tube on metal structure comprising opening, comprises positioning tube around opening located in wall of structure so that inner side of tube is in fluid communication with opening, and welding tube to wall of structure

摘要

The process comprises positioning a tube (3) around an opening (2) located in a wall of a metal structure (1) so that an inner side (4) of the tube is in fluid communication with the opening, and welding the tube to the wall of the structure by plasma arc around an external periphery of the tube. The metal structure further comprises a curve, and is a plate, sphere or a base of pressure vessel. An extreme edge of the tube and an edge of the opening comprise a chamfered edge (5), which is mechanically machined as V, Y or U shape. The chamfered edge forms a heel. The process comprises positioning a tube (3) around an opening (2) located in a wall of a metal structure (1) so that an inner side (4) of the tube is in fluid communication with the opening, and welding the tube to the wall of the structure by plasma arc around an external periphery of the tube. The metal structure further comprises a curve, and is a plate, sphere or a base of pressure vessel. An extreme edge of the tube and an edge of the opening comprise a chamfered edge (5), which is mechanically machined as V, Y or U shape. The chamfered edge forms a heel. The plasma arc jet generates a complete fusion of the heel along its thickness. The plasma welding of each tube is made in a single pass. The process further comprises filling a groove with a molten metal by deposition and fusion of metal wire. The tube has a minimum external diameter of 80 mm, and a minimal thickness of 5 mm.