Abstract
The hot wire GTAW (TIG) process is an under-utilized technology that can pay big dividends in the right application and when used in industries requiring high quality, high productivity welding. Although the GTAW process has a much lower deposition rate than GMAW (MIG), the quality is generally superior. When hot wire technology is used in conjunction with GTAW, especially in downhand welding on plate or on larger diameter pipe, deposition rates can approach that of MIG.
One example of the use of hot wire GTAW technology is provided by a manufacturer of differential pressure flow sensors in Colorado. This company has used an advanced Windows-based 400 Amp power suppy/controller to control the weld parameters and to turn on a separate hot wire GTAW power supply as well as a rotary positioner. They have made over 8,300 welds on a variety of corrosion resistant materials in just four years with virtually no rejects. 1
Hot wire GTAW narrow groove welding has been used extensively for the welding of nickel-based alloys, a wide range of steel alloys as well as reactive metals such as titanium. Hot wire GTAW equipment is finding increasing uses in industry applications as varied as valve manufacture, oil and gas industry components, and components used in nuclear power generation.
Recent developments in hot wire GTAW equipment as well as the benefits and limitations of the process will be presented.