Welding is a serious job that requires tremendous skill, extensive knowledge, practice, and most importantly, commitment. If you are just starting out, the sheer amount of information on welding can be overwhelming for you.
When I first began welding 15 years ago, the nomenclature of welding confused the heck out of me. But I didn’t give up.
You shouldn’t too. To all the welding enthusiasts reading this, I am going to try and simplify different types of welding for you. My aim is to help you understand the pros and cons of each type of welding techniques and their individual applications across various industries.
Let’s hope that by the end of this article, you’ll figure out the correct type of welding process for your choice of material.
Let’s cut to the chase, shall we?
9 Different Types Of Welding Processes
1. MIG or Metal Inert Gas/ Gas Metal Arc Welding (GMAW)
Industry veterans fondly call it the most beginner-friendly welding process of all time. They are right. It is the easiest type of welding technique to master if you are new to this world. Easy because it takes minimal cleanup and very less equipment to produce clean, visually-pleasing beads.
MIG stands for Metal Inert Gas. This process is also known as Gas Metal Arc Welding (GMAW). In this manual process, we fuse two metal pieces together by continuously feeding the filler material through a welding wand.
The filler material for this purpose is a consumable wire electrode. You will also need a shielding gas for this to protect the arc from external elements e.g wind, dust and rain.
MIG welding is commonly used for automotive repair and in the construction and plumbing industry. On the downside, MIG welds are considered to be structurally weaker and therefore, less durable than the more advanced TIG, Flux-cored, and Plasma Arc Welds. Also, you can’t weld thicker materials using this technique.
2. Stick or Shielded Metal Arc Welding
This one is an archaic method of welding but still quite popular among specialists. It is frequently used in repair works, plumbing, steel fabrication, manufacturing, and construction industry to fuse beefier metals. Hobbyists and beginners can polish their skills with this method as it requires only a couple of inexpensive tools.
It doesn’t require an external supply of shielding gas. Therefore, you can work on this process outdoors in windy conditions. This old but gold manual welding technique works on rusty, dirty, painted metals as well.
This method requires a stick or consumable electrode. This electrode houses a solid metal rod at its core which is coated in flux. The electric current forms an arc that connects the base of the “stick” to the welding metal.
At an intense temperature of 6500°F, the electrode melts into the weld pool and provides filler material for the joint.
The flux creates a gas cloud during the process to protect the molten metal from oxidation. Although this method doesn’t result in the cleanest welds, it can be used on different types of metals. When the gas cools down and settles on the metal, it creates slag.
Although more dependable than the very basic MIG welding, stick welding also has drawbacks like shallow penetration, cracking and susceptibility to extreme weather.
3. Flux-cored Arc Welding (FCAW)
Flux-cored isn’t much different from MIG welding. It’s inexpensive, easy-to-apply, versatile, creates neat welds with very little waste and only some amount of slag. Unlike MIG that only works on thin materials, FCAW is a high-heat method that’s only suited for thicker and heavier metals.
Also, it doesn’t require an external supply of gas. This allows the welder the advantage of working outdoors in windy conditions.
Just like MIG, this process also requires continuously fed wire through a torch and a constant supply of voltage power to create the arc. Instead of a solid wire, you have to use a flux-cored wire that shields the arc from contamination.
High electrode efficiency results in less debris to cleanup, resulting in well-finished welds with minimal effort. You won’t need an external gas supply, which makes cost-cutting easier. Due to the ease, efficiency, low cost, and strength of the welds, this method is extensively used for heavy machine repair, automotive repair, plumbing, construction, and maritime industry.
On the downside, you can’t apply flux-cored welding on thinner metals like aluminum. Plus, the process generates a lot of welding fumes too.
4. Submerged Arc Welding (SAW)
It’s another welding process using a consumable electrode method, allowing a deep penetration and strong welds with very little prep work. This method exclusively deals with nickel-based alloys and ferrous-steel.
In SA welding, the entire process takes place under the bed of granular fusible flux. The intense heat makes the flux conductive which forms a path between the electrode and base material.
The flux cover keeps emissions, fumes and spatters to a minimum while also protecting the molten metal from UV radiation. This is the sole reason why SAW is one of the safest and most efficient welding methods we have today. The only true limitation is that it doesn’t work on any type of metal other than ferrous steel and nickel alloys.
5. TIG/ Gas Tungsten Arc Welding (GTAW)
This method uses a non-consumable tungsten electrode and inert shielding gas (mostly argon) to form pure, neat, high-quality welds that can easily withstand years of heavy abuse.
It is a popular method across various big industries including military equipment manufacturing, maritime, and the automotive industry to join thick steel sheets, aluminum, nickel, magnesium, and copper.
For this method, the welder needs to heat up the tungsten using current. When the electrode becomes conductive, it forms an arc that melts a metal wire, forming a weld pool.
Meanwhile, a constant flow of gas protects the weld pool from contamination. You will need both of your hands for TIG welding, one for feeding the wire and the other for holding the TIG torch.
This is a very precise method that requires impeccable skills, focus and practice. That’s mainly because there’s a very small area between the arc and the base metal for you to work with.
When done correctly, it can form strong and aesthetically-sound welds with a negligible amount of waste to clean up. It is mostly used by experienced welders and engineers who seek a high level of precision and control over the weld area.
6. Plasma Arc Welding (PAW)
Like TIG, PAW also allows the welder a great control over the arc and accuracy of the welds. For this method, you will need an advanced torch that features a non-consumable electrode and a copper nozzle with a small tip.
The electric current is pushed through this nozzle which pressurizes the protective gas inside the torch, creating plasma. Next, the plasma gas is heated to a high temperature and ionized which makes it electrically conductive.
You’ll use this ionized plasma to force the electric arc to the base metal plate through a very narrow borehole. This enables the torch to produce an extremely high concentration of heat in a very small area, leading to deep penetration and exceptional accuracy.
Therefore, this process is a staple in aircraft manufacturing industry where we deal with metals 0.015 of an inch. The only downside is that the preparation and required equipment are pretty expensive. Since it’s one of the more complex welding methods, only skilled professionals can perform it.
7. Electroslag Welding (ESW)
This is an automated welding technique that’s frequently used in steel fabrication and other big industries. ESW method can be used for welding vertically positioned 25-300 mm thick metals in a single press.
At the start, the welding machine initiates an arc by passing electrical current between a consumable electrode and the base metal plate. This creates a gap that is filled with welding flux powder. The high heat produced by the arc melts this flux and produces molten slag on the weld pool.
The slag’s resistance generates high heat that gradually melts and joins the electrode and base metal pieces. A water-colored copper shoe is added during the process keeps the molten slag in place.
While high deposition rate and the ability to fuse extremely thick metals remain the top advantages of ESW, the toughness of the weld remains questionable. Moreover, this method is only applicable to vertically positioned materials.
Electrogas Welding (EGW) is very similar to this, with one major difference. In Electroslag, the slag extinguishes the arc but not in the gas method. EGW is commonly used in the storage tank and maritime industries.
8. Atomic Hydrogen Welding (AHW)
This precise method is the most efficient way to fuse tungsten, a metal possessing a high heat resistance. With AHW welding, you can produce strong and clean welds without damaging this precious metal.
In this process, two consumable tungsten electrodes are placed in a chamber shielded by hydrogen gas. Hydrogen produces massive heat that forms an arc.
Then, the arc breaks up and recombines the hydrogen molecules which generates a whopping amount of heat (up to 3000 degrees C). This tremendous amount of heat melts the tungsten and creates clean and cohesive welds.
While it certainly produces strong welds, the types of materials it will work on are very limited. No wonder it’s getting slowly superseded by the more advanced and versatile gas metal arc welding.
9. Electron Beam Welding (EBW)
This is a fully automated welding process performed by a machine. It shoots a high-velocity beam of electrons towards the pieces to be welded. The technique transforms the electrons’ energy into kinetic energy that melts and fuses the metal pieces. The whole process takes place in a total vacuum.
EBW is effective for fusing two metals with different melting points and heat conductivities. This complex form of welding is widely used in aircraft engine and fully automated automotive parts manufacturing.
So these were the 9 main types of welding processes for welders of all skill levels. There are about 22-23 other types of welding following the basic principles of these nine techniques. But you don’t have to dig that deep right now. I don’t want you to get overwhelmed by too much information right from the start.
What’s the best welding technique among all of them, you ask? Depends on your skills, type of material you work with and budget. The coolest part about having so many methods available is that both beginners and specialists can explore new possibilities and scale up their business in their own time. Hope that helped.