Gouging is the removal of metal by a thermal process, usually either oxyfuel gouging or air arc gouging. Due to the heat input produced by the oxyfuel process. So it is not always recommended for any special purposes. The base metal must be at least 21oC before any gouging begins and not more than 2600C as measured adjacent to gouge. In 1940s the first carbon gouging torch was developed. Before this development the process required two welders, on to control the carbon arc and the other to guide the air stream. The torch has had both the provision. Most MMAW/ SMAW Power supplies can be used for gouging i.e. rectifier  of higher current range are used for gouging. Air supply must be in between 80psi to 100psi. The minimum pressure is around 40psi. The correct air pressure will result in cuts that are decrease the electrode over heating by increasing its ability to carry higher currents and improves the heat dissipation. It also provides strength for less accidental breakage