GMAW / MIG Welding
Gas Metal Arc Welding (GMAW) is frequentlyreferred to as MIG
/MAG welding.GMAW is a commonly used high deposition rate
welding process.Wire continuously fed from a spool.GMAW is
referred to as a semiautomatic welding process.
The process consist of a DC arc burning between a continuous
filler metal(consumable) and weld spool. The arc and weld area
are enveloped & shielded in a protective gas externally supplied.
The wire is fed through welding torch which is connected to the
positive terminal into the weld zone.
GMAW Welding Benefits
- All position capability
- Minimal post weld cleaning is required
- Easy technique and less operator skill required
- Higher deposition rates and higher productivity
- Long welds can be made without starts and stops
GMAW Welding Shielding Gas
The shielding gas, forms the arc plasma, stabilizes the arc on the metal being
welded, shields the arc and molten weld pool, allows smooth transfer of metal
from the weld wire to the molten weld pool.There're three primary metal transfer
modes: Spray Tranfer / Globular Transfer / Circuiting Transfer.
MIG(Metal Inert Gas) welding means the use of an inert(i.e.non active)gas.MAG
(Metal Active Gas) welding requires the use of an active gas(i.e. carbon dioxide
and oxygen).CO2 is a more commonly used shortening of MAG welding gas &
also used in pure form in some MIG welding processes.However,the presence
of CO2 in shielding gas may adversely affect the mechanical properties of the
weld,in some applications.
The primary shielding gasses used are:
- Argon
- Argon - 1 to 5% Oxygen
- Argon - 3 to 25% CO2
- Argon/Helium
