Introduction
Although the hot wire GTAW process, commonly known as hot wire TIG, was introduced in 1966, its development and application have been slow to take hold. However, recently there has been considerable renewed interest in the process which initially promised “MIG speed with TIG quality.” While there are some limitations, the hot wire gas tungsten arc welding process has found increasing use over a wide range of groove welding, buildup and cladding operations. The development of automated and specialized hot wire equipment has driven application of the process in industries including nuclear, power generation, pressure vessel and offshore oil which all require high productivity-high quality welds.