Submerged arc welding

Submerged arc welding is a type of welding which utilises a large diameter wire electrode, typically 3 or 4mm diameter. The electode is fed into the arc at a controlled rate. The arc is shielded by a granular flux which is poured to form a pile of flux surrounding the arc.

Unlike other types of arc welding, eye protection is not required, since the arc is covered by the flux. Some of the flux is converted to slag by the arc, which protects the weld as it cools. The slag can easily be chipped off the weld when cool. Surplus flux is collected for re-use.

Since the weld is controlled by the welding machine, high quality welds can be produced. Typically, submerged arc welding will be used for high quality, multiple pass welds.

Application There are two main types of submerged arc welding:

• Flat welds - used to join two steel plates together. The welding machine travels along a tracked over stationary work pieces.
• Cylindrical welds - used to build up or coat shafts. The welding machine is static, and the shaft rotates under the welding machine.