Welding

Welding is the most economical and efficient way to join metals permanently. It is the only way of joining two or more pieces of metal to make them act as a single piece. There are many ways to make a weld and many different kinds of welds. Some processes cause sparks and others do not even require extra heat. Welding can be done anywhere… outdoors or indoors, underwater and in outer space.

There are many types of welding method such as:

Shielded metal arc welding (SMAW): also known as "stick welding or electric welding", uses an electrode that has flux around it to protect the weld puddle. The electrode holder holds the electrode as it slowly melts away. Slag protects the weld puddle from atmospheric contamination.

Gas tungsten arc welding (GTAW): also known as TIG (tungsten, inert gas), uses a non-consumable tungsten electrode to produce the weld. The weld area is protected from atmospheric contamination by an inert shielding gas such as argon or helium.

Gas metal arc welding (GMAW) : commonly termed MIG (metal, inert gas), uses a wire feeding gun that feeds wire at an adjustable speed and flows an argon-based shielding gas or a mix of argon and carbon dioxide (CO₂,) over the weld puddle to protect it from atmospheric contamination. The GMAW process is suitable for fusing mild steel, stainless-steel as well as aluminium.

Flux-cored arc welding (FCAW): almost identical to MIG welding except it uses a special tubular wire filled with flux; it can be used with or without shielding gas, depending on the filler.

Submerged arc welding (SAW):uses an automatically fed consumable electrode and a blanket of granular fusible flux. The molten weld and the arc zone are protected from atmospheric contamination by being "submerged" under the flux blanket.

Electroslag welding (ESW): a highly productive, single pass welding process for thicker materials between 25 mm and 300 mm in a vertical or close to vertical position.

The main Types of welding are used in industry and by home engineers are commonly referred to as Mig welding, Arc welding, Gas welding and Tig welding.