Welding Processes

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MIG Welding
Gas Metal Arc Welding (GMAW) is frequently referred to as MIG welding. MIG welding is a commonly used high deposition rate welding process. Wire is continuously fed from a spool. MIG welding is therefore referred to as a semiautomatic welding process.
MIG Welding Benefits
All position capability
Higher deposition rates than SMAW
Less operator skill required
Long welds can be made without starts and stops
Minimal post weld cleaning is required
MIG 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, and allows smooth transfer of metal from the weld wire to the molten weld pool. There are three primary metal transfer modes:
Spray transfer
Globular transfer
Short circuiting transfer
The primary shielding gasses used are:
Argon
Argon - 1 to 5% Oxygen
Argon - 3 to 25% CO2
Argon/Helium


CO2 is also used in its pure form in some MIG welding processes. However, in some applications the presence of CO2 in the shielding gas may adversely affect the mechanical properties of the weld.
Common MIG Welding Concerns
We can help optimize your MIG welding process variables. Evaluate your current welding parameters and techniques. Help eliminate common welding problems and discontinuities such as those listed below:
Weld Discontinuities
Undercutting
Excessive melt-through
Incomplete fusion
Incomplete joint penetration
Porosity
Weld metal cracks
Heat affected zone cracks
MIG Welding Problems
Heavily oxidized weld deposit
Irregular wire feed
Burnback
Porosity
Unstable arc
Difficult arc starting



























TIG Welding
Gas Tungsten Arc Welding (GTAW) is frequently referred to as TIG welding. TIG welding is a commonly used high quality welding process. TIG weld...