Arc Welding

MIG Welding	MMA Welding	TIG Welding
Plasma Welding	FCAW	MCAW
SAW	Plasma Cutting	MIG Brazing
Air Arc Gouging	MMA Gouging	High Disposition MIG

Arc welding is the most widely used means of joining metals and alloys by fusion techniques in industry today and is of profound importance to industrialised and manufacturing countries.

An arc welding process use the heat generated by an arc struck between an electrode and the workpiece to melt and fuse metal in the joint area. An arc cutting process uses heat generated in a similar manner but here the objective is to melt and remove metal.

The main arc welding processes in use today include MMA, MIG, TIG, FCAW, MCAW, and submerged arc. Others are MIG brazing, plasma welding, and variants of the main processes such as twin-wire MIG and high deposition MIG. The main cutting processes are plasma, air-arc and MMA gouging and cutting.

In most arc welding processes the electrode is consumed to form weld metal, but it may also be a non-consumable electrode, as in TIG and plasma welding. The latter two processes can operate without filler but when required filler may be added. Consumables can be solid bare wire, flux coated wire, or tubular wire with a flux or metal powder filling.

Each process provides a protective gas cover for both the consumable and the molten weld pool to prevent oxidation or contamination. This may be in the form of an external shielding gas, as in MIG, TIG, FCAW, MCAW and plasma welding. The gas cover can also be generated by a flux, as in MMA, submerged arc and self-shielded FCAW. These processes, and FCAW, also produce a slag covering on the weld metal surface as additional protection.

Equipment requirements are many and various ranging from simple generators to extremely sophisticated automated and robotic units depending on the process and the application. The speed of welding, deposition rate, and productivity of the processes also varies enormously from one process to another.

Arc welding and cutting processes may be applied to a wide range of metals and alloys and are in use in nearly all areas of industry.

The main safety issues are electrical, radiation, heat, and welding fume.