Submerged Arc Welding (SAW)

Submerged Arc welding is an alluring process to weld on large surfaces like pipes, vessels and heavier wall thickness components in general. It is a common arc welding process that involves the formation of an arc between a continuously fed wire and the work piece. 

The Submerged Arc Welding process is different from other arc welding processes because here the arc is not visible; it is covered by the blanket of powdered flux granules. The flux granules have compounds like lime, silica, manganese oxide, calcium fluoride, etc.

In this process, the pressure is not used and filler metal is obtained from bare wire that is continuously fed through the blanket of flux, once the flux is melted by the heat of the arc it becomes highly conductive. Hence it generates a protective gas shield and slag, which protects the weld zone from contamination, which helps in reducing the cooling rate and helping to shape the weld contour.

The process is limited to a horizontal-fillet welding position, but with a high deposition rate. This welding process is usually applied to carbon steels, low alloy steels, stainless steel and nickel-based alloys. Deep weld penetration and thick materials can be welded through this process.

The SAW process is normally operated with a single wire using either AC or DC current, there are no. variants including the use of two or more wires called as TANDEM , adding chopped wire to the joint prior to welding and then use of metal powered additions.  

The Submerged Arc Welding process has a high deposition rate to be precise  45kgs/hr. A very low amount of smoke is visible in the process, no edge training is required under this process, the process can be performed indoor/outdoor and no weld sprinkles erupts as it is submerged within the flux. This type of welding is generally used heavy thickness long seam welding.