By Alexander Safta

Welding has been a crucial part of various manufacturing processes since the mid-19thcentury when the first form of welding took place [1]. In this blog, I will go in depth on the four main types of welding found in the manufacturing industry today.

Shielded Metal Arc Welding

In this type of welding, the welder carries out a form of stick welding by using a consumable stick electrode which is covered in flux. The welder will move the stick along the desired weld path and when doing so, the consumable electrode will melt into a liquid due to the heat provided from the electrical arc in between the work piece and electrode tip. Once that liquid cools, it will then solidify the two pieces of metal together. [2]
SMA welding was one of the first types of welding ever introduced and remains quite popular today due to its simplistic nature. It is commonly found in the maintenance as well as the repair industry and the main materials this type of welding is used for are iron and steels. [3]

Figure 1. Shielded Metal Arc Welding Process [4]

Gas Metal Arc Welding (MIG Welding)

In this type of welding an electric arc, which is formed between a consumable wire electrode and the metal work piece, is used to melt the consumable electrode being fed through the nozzle tip. While the metal is being melted, a shielding gas will also blow through the welding gun to protect the weld from outside contaminants. [5]
This form of welding has become today’s most popular industrial welding process. A big reason for this has to do with its ease of adaptability into an automated robotic application. This welding process is used most commonly on aluminums as well as steels. [5]

Figure 2. MIG Welder Diagram [6]

Flux Cored Arc Welding

Flux Cored Arc Welding, or FCAW, is very similar to Gas Metal Arc Welding however, there are two major difference. The differences between the two types of welding are firstly, the electrode feeding out of the nozzle is hollow and filled with flux. Secondly, due to the flux being present inside the electrode, there is usually no need for a shielding gas to be blown out of the nozzle. [5]

This type of welding is commonly used in the construction industry due to easy transport and short weld duration. It is commonly used on steels and nickel alloys. [7]

Figure 3. Flux Cored Arc Welder [7]

Gas Tungsten Arc Gas Welding

In this particular type of welding also known as TIG welding, the welding process involves an electrical arc formed between a non-consumable tungsten electrode and the work piece metal. The main difference with this type of welding is a filler metal rod is melted and used to create a weld pool which will solidify and strengthen the weld. [8]

The main application for this type of welding is the aerospace industry and it is used mainly for welding thin pieces of stainless steel and aluminum. [8]

Figure 4. TIG Welding Diagram [8]

References:

[1] The History of Welding. (n.d.). Retrieved January 31, 2019, from https://www.millerwelds.com/resources/article-library/the-history-of-welding

[2] Ed, L. (2014, December 04). 4 Popular Types of Welding Procedures.

[3] Shielded metal arc welding. (2019, January 24). Retrieved January 31, 2019, from https://en.wikipedia.org/wiki/Shielded_metal_arc_welding

[4] Main Page. (n.d.). Retrieved January 31, 2019, from https://commons.wikimedia.org/wiki/Main_Page

[5] Gas metal arc welding. (2019, January 15). Retrieved January 31, 2019, from https://en.wikipedia.org/wiki/Gas_metal_arc_welding

[6] Chandler, T. (2018, May 30). Quora – A place to share knowledge and better understand the world. Retrieved February 1, 2019, from https://www.quora.com/What-is-the-difference-between-mig-welding-and-seam-welding

[7] Flux-cored arc welding. (2019, January 08). Retrieved January 31, 2019, from https://en.wikipedia.org/wiki/Flux-cored_arc_welding

[8] Gas tungsten arc welding. (2019, January 27). Retrieved January 31, 2019, from https://en.wikipedia.org/wiki/Gas_tungsten_arc_welding