Double-sided arc welding process

Double-sided arc welding (DSAW) is a novel process invented and developed at the University of Kentucky. The uniqueness of this process lies in its strong penetration capability and its symmetric hour glass-shaped welds. The early work on DSAW was done using the tungsten of a gas tungsten arc welding torch as the second electrode. Later work showed that a metal backing bar can act in the same capacity. The applicability and robustness of the modified system has been verified by making welds under different positions and different fit-up gaps. With the addition of filler metal, positive reinforcement has been achieved on the both sides of the weld and thus made it feasible to make welds on plates up to 12.7 mm (1/2 inch) thick in a single pass without bevels. Further, various tests have confirmed that the welds made using DSAW on DH 36 steel satisfy all the requirements of mechanical properties, including hardness, toughness (both weld metal and HAZ), tensile, bend, etc.