4 Types of Welding Processes

Jun. 17, 2022

As a welding wire supplier, we share with you 4 types of welding processes.

Gas Metal Arc Welding (GMAW/MIG)

This style of welding is also referred to as Metal Inert Gas (MIG). It uses a shielding gas along the wire electrode, which heats up the two metals to be joined. This method requires a constant voltage and direct-current power source, and is the most common industrial welding process which includes plate and large bore pipe.

The GMAW/MIG welding process uses four primary methods of metal transfer:

1. Globular transfer produces a rougher weld bead due to metal droplet size and the propensity for spattering. This method is useful for welding thick metal plates in horizontal positions.

2. Short-circuiting works as the name implies – the welding wire contacts the base metal in a quickly repeated tapping method many times per second. Because little spattering is produced in the process, this method can be used in any welding position.

3. Spray Transfer transmits tiny droplets of molten metal in such a steady fashion that it maintains a steady-contact arc weld during the process. Even though this method produces little splatter, it is best to use on horizontal pieces that are thick and flat.

4. Pulsed-spray is very similar to Spray Transfer, but uses a high-low current pulse to allow micro-cooling periods. Because of this type of delivery, this process can be used on a wide variety of metal plate thicknesses, and in almost all welding positions. Note that when we use the term “cooling” when describing pulsed-spray, the moments of lower voltage that provide a cooler weld are still several thousand degrees Fahrenheit. It is only considered cooler relative to the high-voltage portion of the cycle. All welding uses extreme temperatures.

Gas Tungsten Arc Welding (GTAW/TIG)

TIG involves using a non-consumable tungsten electrode to create an arc and an inert gas (such as argon or helium) to shield the weld pool from contaminants. TIG welding requires a high level of skill and is typically used for thin materials or for welding materials that are sensitive to contamination.

Welding together thick sections of stainless steel or non-ferrous metals is the most common use for this method. It is an arc-welding process that uses a fixed consumable tungsten electrode to produce the weld. This process is much more time consuming than MIG, Stick or Flux Cored Arc Welding.

The melting point of non-ferrous metals vary considerably, so care must be taken in identifying the composition of the base metal. Stainless Steel and Steel both contain Iron, however, to be considered Stainless Steel, the metal must contain at least 11% Chromium. Carbon Steel melts in the 2,600 to 2,800-degree F range.

The presence of 11% chromium in stainless steel narrows that temperature range to the 2,750+/- degree F mark. But nothing shows welding skills more than the intricate ability to TIG weld aluminum. This skill takes a steady hand, trained eye, and an artistic touch to create a smooth, amazing weld.

Shielded Metal Arc Welding (SMAW)

Also known as "stick welding," SMAW involves using an electric current to create an arc between a consumable electrode and the base metal. The electrode is coated in a flux that helps to protect the weld pool from contaminants and provides a slag layer on top of the weld that must be chipped off after the weld cools.

This is often used in the construction of steel structures and in industrial fabrication to weld iron, steel and using the open V-Groove when welding with mild steel pipe.

It is vital that the welder must be able to weld to a level in which their work can pass a destructive type of bend test. While shielded metal arc welding is used to join carbon steel, alloyed steels, stainless steel, cast iron, and ductile iron, it can also be used for some non-ferrous metal applications like Nickel and Copper. It is rarely used on Aluminum.

Submerged Arc Welding Wire

Submerged Arc Welding Wire

Flux Cored Arc Welding (FCAW)

This was developed as an alternative to shield welding. The semi-automatic arc weld is often used in construction projects, thanks to its high welding speed and portability. This method has many variables making it applicable in a variety of welding projects. Variables often depend on the model of welder being used, and what type of wire was chosen for the application.

The flexibility is broadened by the many operating angles, voltage levels, polarity used, as well as the speed of the wire feed. Due to the potential of faster welding speeds, the newly joined metal cools quicker. If the welding technician is using a flux cored wire, he or she must be on the lookout for porosity in the welded joint.

Flux Cored Arc Welding is best used in either outdoor settings or under industrial ventilation hoods, due to the amount of smoke and fumes created during the welding process.

We are a welding wire supplier. If you are interested in our prodcts, please contact us now!