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Basic welding guide
MIG (GMAW/FCAW) Basic Welding Technique
Two different welding processes are covered in this section (GMAW and FCAW), with the intention providing the basic
concepts in using the MIG mode of welding, where a welding gun is handheld, and the electrode (welding wire) is fed into
a weld puddle, and the arc is shielded by an inert welding grade shielding gas or inert welding grade shielding gas mixture.
GAS METAL ARC WELDING (GMAW): This process, also known as MIG welding, CO2 welding, Micro Wire Welding, short arc
welding, dip transfer welding, wire welding etc., is an electric arc welding process which fuses together the parts to be
welded by heating them with an arc between a solid continuous, consumable electrode and the work. Shielding is
obtained from an externally supplied welding grade shielding gas or welding grade shielding gas mixture. The process is
normally applied semi automatically, however and fairly thick steels, and some non
‐
ferrous metals in all positions.
FLUX CORED ARC WELDING (FCAW): This is an electric arc welding process which fuses together the parts to be welded by
heating them with wan arc between a continuous flux filled electrode wire and the work. Shielding is obtained through
decomposition of the flux within the tubular wire. Additional shielding may or may not be obtained from an externally
supplied gas or gas mixture. The process is normally applied semi automatically; however, the process may be applied
automatically or by machine.
It is commonly used to weld large diameter electrodes in the flat and horizontal position
and small electrode diameters in all positions.
The process is used to a lesser degree for welding stainless steel and for
overlay work.
