METHOD AND APPARATUS FOR METAL SHIELD-GAS WELDING

摘要

The invention relates to a method of gas metal arc welding in which an electric arc burns in a shield gas environment during welding for production of a weld along a welding path between at least one workpiece to be welded and a melting wire electrode (1) that is in particular continuously fed to the at least one workpiece. At the starting end of the weld to be produced, chronologically before ignition of the electric arc between the at least one workpiece and the wire electrode (1), a nonconsumable electrode (2) is moved toward the at least one workpiece. Between the at least one workpiece and the nonconsumable electrode (2), in a shield gas environment an electric arc is ignited that locally preheats the at least one workpiece at the starting ending end of the weld to be produced. After the preheating the nonconsumable electrode (2) is removed from the at least one workpiece and after removal of the nonconsumable electrode (2) the electric arc is ignited between the at least one workpiece and the wire electrode. The invention further relates to a torch head for carrying out the method.

主权项

1. In a method of gas metal arc welding in which an electric arc burns in a shield gas environment during the welding for production of a weld along a welding path between at least one workpiece to be welded and a melting wire electrode that is continuously delivered to the at least one workpiece, the improvement comprising the steps of:
at the location of the starting end of the weld to be produced, chronologically before ignition of the electric arc between the at least one workpiece and the wire electrode moving a nonconsumable electrode toward the at least one workpiece, between the at least one workpiece and the nonconsumable electrode and in a shield gas environment igniting an electric arc to locally preheat the at least one workpiece at the starting end of the weld to be produced, after the preheating, removing the nonconsumable electrode from the at least one workpiece, and after the removal of the nonconsumable electrode igniting the electric arc ignited between the at least one workpiece and the wire electrode.