FLUX CORE WIRE
Flux-cored arc welding (FCAW or FCA) is a semi-automatic or automatic arc
welding process. FCAW requires a continuously-fed consumable tubular
electrode containing a flux and a constant-voltage or, less commonly, a
constant- current welding power supply. An externally supplied shielding gas
is sometimes used, but often the flux itself is relied upon to generate the
necessary protection from the atmosphere. The process is widely used in
construction because of its high welding speed and portability.