Plasma cutting power sources and welding machines

Metal inert gas (MIG) welding or metal active gas (MAG) welding, known according to the AWS terminology as Gas metal arc welding (GMAW), is a welding process in which an electric arc is formed between a consumable wire electrode and the workpiece metal, which heats the workpiece metal, causing them to melt, and join. Along with the wire electrode, a shielding gas is fed through the welding torch, which shields the process from contaminants in the air. The fact that it’s a continuous wire welding process grants a high productivity and, at the same time, the presence of gas allows operation without slag (both these features make this procedure more advantageous in comparison with MMA welding).
Today, GMAW is the most common industrial welding process, preferred for its versatility, speed and the relative ease of adapting the process to robotic automation. Unlike welding processes that do not employ a shielding gas, such as shielded metal arc welding, it is rarely used outdoors or in other areas of air volatility. Some welding machines include the use of a related process, flux cored arc welding, that often does not utilize a shielding gas, instead employing a hollow electrode wire that is filled with flux on the inside.
To perform gas metal arc welding, the basic necessary equipment is:
1. Welding power source.
2. Welding gun with a dual function: to start the electric arc between the wire and the workpiece and to fed the shielding gas.
3. Wire feed unit.
4. Welding wire.
5. Ground clamp.
6. Shielding gas supply.