In SAW (Submerged Arc Welding) an arc is struck between the work piece and the end of a consumable electrode, both of which are covered by a layer of granular flux (hence ‘submerged’ arc). The arc is therefore hidden. Some of the flux melts to provide a protective slag cover over the weld pool. The remainder is collected for re-use.

The electrode is mostly a solid wire but lately cored wires have been introduced. Submerged Arc Welding is principally carried out with fully automatic equipment, although there are hand-held welding guns for the process. To increase productivity an arrangement with several electrodes can be introduced. Because of its high metal deposition rate it is particularly suited to long straight joints of good quality in the flat position. It is widely used in the pressure vessel, chemical plant, heavy structural, repair and shipbuilding industries.