Arc welding method and apparatus

Abstract

A method of consumable electrode arc welding is shown wherein the leading consumable electrode wire is mounted in parallel with a trailing filler wire, the latter inserted into a molten metal bath. Welding current is divided between the consumable electrode wire and the filler wire. These modifications improve the wettable boundary of the molten metal bath, prevent defects in the weld, and provide a high speed, highly efficient and high quality method of welding carbon steels, alloy steels, as well as aluminum and its alloys in a fully automatic as well as a semiautomatic operation. In an apparatus utilizing the above method, a single torch contains the consumable electrode and filler wire. One or more insulating contact tubes containing filler wire are mounted in a gas shield in parallel with a conductive contact tube containing consumable electrode wire. The unit is small in size and light-weight, and thus convenient for a welder to carry or hold during operation. Appropriate selection of one of the filler wires provided allows multidirectional operation without reorienting the torch. The unit produces a high-quality weld at rapid welding rates and is suitable for automatic and semiautomatic operation.