DSAW

DSAW stands for Double-Submerged Arc Welding, a welding process used to join metals, especially for long seams on large-diameter components such as pipes and pressure vessels. In DSAW, two submerged arc welding heads operate from opposite sides of the joint, welding the seam simultaneously. The process uses flux to blanket the arc and weld pool, providing shielding without a fused gas shield. Electrodes, typically solid wires or flux-cored wires, feed into the molten weld pool in a controlled manner, and the flux generates slag that protects the weld as it cools.

DSAW is commonly implemented in automated or semi-automatic production environments, often on long-component fabrication lines or in field installations where large quantities of identical welds are required. It is especially associated with carbon and low-alloy steels and is well suited to thick sections and full-penetration joint configurations. Preheating and interpass temperature control are frequently used to manage hydrogen content and distortion, and post-weld heat treatment may be specified for some materials.

Advantages of DSAW include a high deposition rate, deep penetration, and the ability to produce high-quality, full-penetration welds from opposite sides, which can reduce distortion and improve productivity compared with single-sided welding. The dual-head setup also allows for better process stability and repeatability in mass production.

Limitations include higher equipment and maintenance costs, the need for precise joint fit-up and alignment, and flux handling and recycling requirements. DSAW is most effective for linear seam welds on large components and is less adaptable to complex or highly irregular geometries.

See also: Submerged Arc Welding (SAW), welding automation, pipe welding.