MIG/MAG welding procedure

19 September 2019
MIG/MAG (Metal Inert Gas / Metal Active Gas) GMAW (Gas Metal Arc Welding)

Arc welding with continuous wire electrode with gas shield (MIG/MAG) is one of the most economical types of process, best suited for very high rates of production. The basic difference between MIG and MAG lies in the type of gas used. The choice is therefore dictated by the type of metal to be welded.

This electric welding process fuses together the parts to be welded using the heat of an arc struck between the solid or continuous wire electrode and the base metal. The filler metal is obtained by continuous fusion of the wire fed into the arc by a wire feeder. A gas shield is introduced into the arc by means of a special torch. The process can be powered by direct current (DC).
This type of welding can also be used with a manual torch and fully automated support systems such as robots.

The following items are necessary for this type of welding:

  • A power source;
  • A clamp with ground lead;
  • A torch that performs a twofold function in this case: strikes an arc between the wire and the weld workpiece and at the same time produces a gas shield to protect the welding bath;
  • Spool with welding wire (solid wire or cored wire);
  • Wire feeder: a device with an automatic mechanism that pushes the electrode wire toward the torch wound onto the spool;
  • Cylinder of gas (inert or active depending on the metal to be welded);
  • Inert gases are: argon, helium and argon-helium mixtures;
  • Active gases: carbon dioxide, mixtures of organ with oxygen or carbon dioxide;