Patent ID: 7485826

Claim:
A process for welding one or several metal pieces comprising the steps of: i) providing a consumable wire having a fusible extremity, ii) providing at least one metal piece to be welded, iii) providing a TIG welding torch which has a torch body and a tungsten electrode which has a sharpened end, and said torch further comprising at least one wire guide-nozzle assembly, said assembly comprising at least one nozzle for delivering said gas mixture, said nozzle comprising a first axis longitudinally oriented with said nozzle, and at least one wire-guide system for guiding at least said consumable, wire said wire-guide system comprising a first section, said first section comprising a downstream end of said wire-guide system, wherein said downstream end directs said consumable wire into said nozzle, wherein said fusible extremity of consumable wire and said tungsten electrode lie in one and the same plane, wherein said nozzle further comprising a peripheral wall, said peripheral wall having at least one cut-out through which said wire-guide system passes, iv) orienting the fusible extremity of the consumable wire relative to the extremity of the tungsten electrode at an angle of between about 5° and about 50° relative to each other, and guiding said wire in such a manner that an end of said wire grazes said sharpened end of said tungsten electrode and then enters into an electrical spot created by said tungsten electrode on said at least one metal piece to be welded, and wherein said at least one metal piece is chosen among metal sheets or plates having a thickness from between 0.5 and 4 mm made of carbon steel, ferritic or austenitic stainless steel, nickel-based alloys, titanium/zirconium-based alloys or tantalum-based alloys, aluminum or magnesium light alloy.