Metal Inert Gas (MIG) welding or Gas Metal Arc Welding (GMAW) as it is sometimes called, has been the most widely used welding method since it was developed in the 1940s. It’s used to weld both ferrous and non-ferrous metals such as standard carbon steels, aluminium, nickel alloys and stainless steel and is suitable for a wide range of applications including small fabrications or repairs through to large structures, the automobile and shipbuilding industries and robotic welding.
The MIG Welding Process
Throughout the MIG welding process, a wire connected to a source of +ve direct current acts as an electrode that is continuously passed through a welding gun creating an electrical arc to melt and join two pieces of metal. It is considered a semi-automatic process meaning that the welder still requires skill but that the welding machine will keep filling the joint being welded. In cases where a robot takes over this process, it becomes automatic welding.
At the same time as the wire electrode is passed through the welding gun, a flow of an inert gas is applied over the weld pool. The primary function of this gas is to protect the molten electrode, the weld pool and heat affected zone of the metal from the damaging effects of the surrounding atmosphere and prevent oxidisation, but also to create the optimal welding characteristics for the arc.
Advantages of MIG Welding
- Faster welding speeds –high quality and long continuous welds can be produced much more quickly than traditional welding techniques.
- Versatility – it can be used with a wide variety of metals and alloys and thicknesses, and can be operated several ways i.e. automatic and semi-automatic.
- Requires little clean up – the shielding gas protects the welding arc so produces a clean weld with little splatter or slag to chip off.
- No fluxes required in most cases – meaning there is no chance of slag getting trapped in the weld metal.
As with all welding procedures, MIG welding requires you to take safety precautions as it can be dangerous and there are a number of hazards associated with it. Therefore before undertaking any welding job, ensure you have the necessary and correct protection.
If you require our assistance regarding any aspect of the MIG welding process please don’t hesitate to contact us on 0114 243 0555.