"Why is it called submerged arc welding?"

"The arc burns underneath a blanket of granular flux, so it's literally submerged. You can't see the arc during welding. The flux melts around the arc to form a protective slag over the weld, and unfused flux is recovered and reused. This total shielding produces very clean, porosity-free welds."

"What is the deposition rate of submerged arc welding?"

"Single-wire SAW deposits 15-45 lbs/hour depending on wire size and current. Tandem (two-wire) setups push 40-100+ lbs/hour. For comparison, MIG tops out around 8-12 lbs/hour and stick maxes at about 5 lbs/hour. SAW's deposition rate is unmatched for long, heavy welds."

"Can you do submerged arc welding out of position?"

"No. SAW is limited to flat and horizontal positions because the granular flux relies on gravity to stay in place over the weld pool. The process also requires mechanized travel (tractor, gantry, or boom), so it's not a manual process. These limitations are why SAW dominates shop fabrication but isn't used in field construction."

Submerged Arc Welding (SAW) Guide

Submerged arc welding process explained: flux selection, wire and current parameters, single vs tandem wire setups, and applications in pressure vessels, structural beams, and shipbuilding.

Submerged arc welding (SAW) deposits more weld metal per hour than any other arc welding process. A continuously fed wire electrode arcs beneath a blanket of granular flux, completely hiding the arc from view. The flux melts to form protective slag, shields the weld from contamination, and can add alloying elements to the deposit. Unfused flux gets vacuumed up and recycled.

Where SAW Is Used

SAW is a production shop process. You’ll find it in pressure vessel fabrication, wind tower manufacturing, structural steel beam production, shipbuilding, pipe mills, and heavy plate joining. Anywhere you need long, straight (or circumferential) welds on thick material in the flat or horizontal position, SAW is the fastest and most cost-effective choice.

The process typically runs on mechanized equipment: tractors that ride along the joint, column-and-boom manipulators, or rotary positioners that spin cylindrical parts under a fixed welding head. Automation is the default since travel speed and electrode placement need consistency that manual operation can’t provide.

Process Parameters

SAW runs at high currents, typically 300-2000 amps for single-wire setups. Wire diameters range from 5/64" to 1/4". Voltage, travel speed, and electrode stick-out interact to control bead shape and penetration. DC positive (DCEP) provides deep penetration. AC eliminates arc blow on thick weldments and is standard for tandem setups where multiple arcs operate close together.

Tandem SAW uses two or more wire electrodes in sequence. The lead wire (usually DC) provides penetration, and the trail wire (usually AC) fills the joint. This configuration doubles or triples deposition rates and is standard on high-production applications like pipe seam welding and pressure vessel longitudinal seams.

Flux Types

Fused fluxes produce consistent results and generate less fine dust. Bonded (agglomerated) fluxes allow custom chemistry and add alloying elements to the weld. Active fluxes contain manganese and silicon that transfer into the weld metal and affect mechanical properties. Neutral fluxes don’t change weld chemistry regardless of arc voltage changes. Flux selection depends on the base metal, required mechanical properties, and welding parameters.

Articles in This Section

Guides here cover flux selection, wire/current charts, tandem SAW setup, and applications for specific industries.