Keyhole double-sided arc welding process

Double-sided arcing uses two torches on the opposite sides of the workpiece to force the welding current to flow through the thickness. If a keyhole is established through the thickness, part of the welding current will flow through the keyhole and maintain the electric arc inside the keyhole. It was found the through thickness direction of the welding current and the establishment of a keyhole both helped enhance the concentration of the arc and the density of the arc energy. In addition, the presence of the arc in the keyhole provided a mechanism to directly heat the workpiece through the thickness, as well as a mechanism to compensate the energy consumed during heating. In this study, a double-sided arcing technique was developed into a welding process for deep, narrow joint penetration. Experiments confirmed the characteristics of this process.