EVALUATING THE EFFECTS OF WAVEFORM MANIPULATION for the Tandem AC-SAW Process

摘要

The submerged arc welding (SAW) process is commonly used for fabricating large diameter and/or thick-walled components because of excellent productivity, deep penetration, and high quality. During SAW, the welding arc is established beneath a powdered flux; as a result, the process is predominantly limited to the flat welding position, which reduces the possible applications of this productive, high quality process. Furthermore, while the large currents permit high welding deposition rates and the fusion of thicker base metals, these can also restrict the use of SAW for thinner materials (due to the risk of burn-through), and for smaller diameter pipes (due to a large molten puddle, which has a tendency to spill down the side). SAW has historically been used most commonly with direct current in conjunction with electrode positive polarity because of its good arc stability and deep penetration.