Thin-sheet metal welding

Abstract

Tungsten inert gas (TIG) welding is widely used in industry, mainly in manual applications and automatic welding. If the main advantage is its excellent weld quality, the main drawback is the welding speed and penetration compared with other welding processes. The TopTIG welding processes have been developed to improve robotized TIG welding, with the objective of combining TIG quality with MIG productivity. The key part of this new technology is an original torch concept: the wire feed is oriented at an angle close to the tungsten electrode and traversing the gas nozzle. This configuration provides the advantage of reduced overall dimensions and enhanced accessibility of the torch for robotic welding of complex geometries. There is also no need to maintain constant torch and wire feed orientation versus the joint axis, and in this way the sixth axis of the robot is liberated. Several technical features, such as an automatic electrode changer and a push–pull wire feeder, are associated with the new torch design. Applications have been developed for the braze welding of galvanized thin sheets with CuSi3 wires, without spatter. Other applications can be found in welding stainless steel or aluminium, such as in the food industry, manufacturing, furniture and bicycle production.