There are many Welding types, each with its advantages and disadvantages.
It’s essential to learn each as each will be more suited to a particular job.
More than 30 different welding types exist, ranging from simple oxy-fuel to high-tech processes such as laser beam welding.
What Is Welding?
Welding is a fabrication process that uses intense heat, pressure, or both to combine two materials, such as two pieces of pipe.
Various welding methods exist for different purposes and use varying techniques, weld positions and other methods.
For more information on Welding, please visit our blog post “What Is Welding?” which provides an in-depth explanation of each welding type.
Types Of Welding
There are multiple types of welding available today, from manual to fully automated.
The four most common types used here at Varlowe are:
- Metal Inert Gas (MIG)
- Flux-Cored Arc Welding (FCAW)
- Tungsten Inert Gas (TIG)
- Shielded Metal Arc Welding (SMAW Or Stick)
Let’s look into each of them in more detail.
Metal Inert Gas (MIG or GMAW)
MIG welding is a popular and one of the most accessible welding types.
The semi-automated process developed in the 1940s is a subtype of GMAW (Gas metal arc welding).
MIG is one of several welding methods that use electricity to join metal together. It requires a Direct Current Positive Electrode (DCEP), also called Reverse Polarity.
It appeals to more people due to its more manageable learning curve. Once the correct settings to the torch and wire feeder are in place, it doesn’t need much to create clean joints.
How Does MIG Welding Work?
MIG is an arc welding process where a constant solid wire electrode feeds from a solid wire reel into a welding gun.
The solid wire is a metal wire that doesn’t contain any flux, meaning that you must use a shielding gas. The wire is coated in copper to help reduce oxidization and prevent rusting, but it may also include manganese, titanium, and silicon.
The wire serves a multi-purpose in the process. It is the heat source and the filler metal for the joint. Hence, MIG Welding can also be referred to as “wire welding”.
The wire feeds through a contact tube made of copper (the contact tip), which conducts current into the wire.
An arc forms between the wire electrode and the metal being worked on when the trigger gets pulled, forming the weld pool.
MIG welding uses a shielding gas to guard the filler material against environmental elements, depending on the welded material. A nozzle that surrounds the wire delivers the gas.
MIG welding is semi-automatic because a power source controls the wire fed rate and the arc length. The operator manually controls the speed of travel and the position of the wire.
What is MIG Welding Used For?
MIG is used for high production welding operations, such as in shops and factories. Its weld quality, long pass capability, speed and increased productivity make MIG welding a top choice.
MIG welding is renowned for its great applicability to metals and alloys. Metals such as mild steel, stainless steel, aluminium and magnesium.
Indoor environments are ideal for MIG because it requires clean surfaces and windless conditions. Otherwise, the gas shielding will be disrupted, allowing reactions and imperfections in the weld.
Typically, Mig welding machines are not very portable and more complex. In addition, shielding gas, electrodes, and replacement tips and nozzles for MIG welding can add up.
Advantages Of MIG Welding
- Higher Productivity
- Simple to Learn
- Excellent Welds
- Clean and Efficient
- Faster Welding Speed
Disadvantages Of MIG Welding
- Limited Positions
- Unsuitable for Outdoor Welding
- Unsuitable for Thick Metals
- Metal Preparation Time
- Can Be Costly
Alternate Names for MIG Welding
- Gas Metal Arc Welding (GMAW)
- Metal Active Gas (MAG)
- Wire Welding
Flux-Cored Arc Welding (FCAW)
FCAW is a variant of the MIG/MAG method.
Both techniques use the same semi-automatic, continuous wire feed machines. Both methods have a very high production rate.
Although there are a lot of similarities, there are a lot of differences. Several things make each better than the other.
The main difference between flux-core and MIG welding is that flux-core does not need a shielding gas.
A flux-cored wire consists of a tubular filler metal with a powdered flux in the centre of the wire. The flux acts as shielding, allowing the operator to weld outdoors when it is windy.
How Does FCAW Work?
Flux-Cored uses the heat generated by an electric arc to fuse the metal.
The arc’s struck between the continuously fed consumable filler wire and the workpiece. The arc melts both the filler wire and the workpiece.
When this wire melts, it creates a gas that protects from oxygen, meaning a shielding gas isn’t required. Although, one can be used to offer more protection.
There are two FCAW operating modes:
- Gas-shielded – An external source supplies a shielding gas, such as a gas cylinder.
- Self-shielding – The shielding gas is from the internal flux within the wire.
What Is FCAW Used For?
FCAW is a highly productive and flexibly welding process.
It works well with a range of alloys, plain carbon, stainless and duplex steels and is also frequently used for surfacing and hard facing.
The high deposition rate provides high-quality welds with a good appearance even at high welding speed and can be used in all positions.
FCAW can also be readily performed outdoors, even in windy conditions, making it a popular method in the construction sector.
Advantages Of FCAW Welding
- High-Quality Welds
- It can be used at high speed due to improved arc stability
- FCAW is excellent for joining thicker metals
- Used in all positions
- Higher wire deposition rates
- It can be used outdoors
- Less pre-cleaning required
- Low porosity, if implemented correctly
Disadvantages Of FCAW Welding
- Produces noxious smoke
- Generates more smoke than other processes
- FCAW electrodes need better handling and storage practices
- The filler material can be more expensive
- Need to remove Slag
- Cant be used on materials thinner than 20 gauge.
Alternate Names for FCAW Welding
- Dual Shield Welding
Tungsten Inert Gas (TIG or GTAW)
TIG Welding (Tungsten Inert Gas) is an arc-based welding process that produces the weld with a non-consumable tungsten electrode.
Developed in the 1940s, it quickly became a popular welding type when it joined magnesium and aluminium. Today it is commonly used for welding stainless steel and non-ferrous materials (e.g. aluminium, magnesium and copper alloys).
It is highly versatile, but it is also one of the more difficult welding techniques to learn.
TIG uses an inert gas shield instead to protect the weld pool. The process was a suitable replacement for gas and manual metal arc welding.
TIG has played a significant role in accepting aluminium for high-quality welding and structural applications.
How TIG Welding Works
TIG welding uses electricity to generate an arc via a tungsten-based electrode located in the welding torch. The arc creates heat which is required to join the metals.
The process also requires a shielding gas, generally Argon, to protect the weld metal from contamination. The welding torch also delivers the shielding gas.
The TIG process needs more experience as there are a lot of variables to control.
For example, You need to coordinate the interaction of a hand-held TIG torch with a filler rod and vary the electrical current. The electrode must be the correct distance from the weld, and both kept in the shielding gas.
This torch creates the heat and arc for welding most conventional metals, including aluminium, steel, nickel alloys, copper alloys, cobalt, and titanium.
A Non-Consumable Tungsten Electrode
The electrode used in TIG is tungsten or a tungsten alloy. The melting point of tungsten is 3,422 °C, the highest temperature among pure metals.
Unlike MIG welding, the high melting point of a TIG welding tungsten electrode signifies that it won’t melt during welding. Instead, the arc from the electrode melts the parent metal.
At the same time, the arc also melts a welding rod of filler metal to form the weld bead.
Inert Shielding Gas
The job of the inert shielding gas is to protect the molten weld pool from atmospheric gases such as oxygen and nitrogen.
The atmospheric gases can cause defects, porosity and embrittlement if they contact the arc or welding metal.
The shielding gas can also help transfer heat from the electrode and helps to maintain a stable arc.
The gas is typically Argon or an argon mixture. Using Helium can provide faster welding under certain circumstances.
The welding machine provides the shielding gas to the TIG torch that holds the tungsten electrode.
What Is TIG Welding Used For?
Many industries use TIG for welding thin workpieces, especially non-ferrous metals.
While you can use a TIG welder for carbon steel, it’s efficient for other metals like stainless steel, aluminium, and titanium.
A well-executed TIG weld is exceptionally high-quality and robust.
TIG can weld fragile metal sections, but as a slower process compared to MIG or arc welding.
TIG is a common type of welding for pipefitters working with high-pressure carbon or stainless pipes, automotive, food production and aerospace applications.
Advantages Of TIG Welding
- Varying Metal Thicknesses.
- Clean Welds
- Used In All Positions (Vertical, Horizontal, Overhead)
- Minimal Smoke
- Colourless Shielding Gas
- Extremely Ductile
- TIG welding machines can also perform stick welding
Disadvantages Of TIG Welding
- Complex with a steeper learning curve
- Only used in a wind-free environment.
- TIG welders are expensive
Alternate Names for TIG Welding
- GTAW – Gas Tungsten Arc Welding.
Shielded Metal Arc Welding (SMAW or Stick)
Stick welding is a manual arc welding method. It uses a consumable electrode covered with a flux to lay the weld.
It is the oldest welding type, developed in Russia back in 1800, and arguably the most widely. The coated electrode came out of Sweden in the early 1900s.
Stick is a popular welding method due to its simple setup, portability, and cost-effectiveness.
Stick welding is very versatile to weld iron, steel, aluminium, nickel, and copper alloys.
How Does Stick Welding Work?
Stick Welding uses a combination of electricity and consumable rod-shaped electrodes (welding rods) coated in flux to create the welded joint.
The flux coating means a shielding gas is unnecessary, unlike MIG and TIG.
Stick Welders require an earthing clamp (which attaches to the workpiece) connected to a ground cable.
When the electrode is brought into contact with the workpiece, it completes the circuit.
An electrical arc that creates intense heat melts both the electrode and the metal, causing it to fuse with the base metal.
The flux covering on the electrode breaks down due to the arc, giving off protective vapours that secure the welding process.
Flux slag on top of the weld pool helps shield against contamination and can be chipped away once cooled. This then reveals the finished weld joint.
Although stick can use AC and DC currents, DC is the preferred polarity for more traditional rods.
This polarity provides a more stable, smoother arc and a higher penetration level into the metal.
Stick performs well outdoors due to its portable design and can create an effective bond on rusty or unclean surfaces.
What Is Stick Welding Used For?
Stick is frequently used for heavy-duty work, including industrial iron, cast iron, and carbon steel. Its also used with low and high alloy nickel and steel alloys.
It’s typical to see stick used in structural applications. Due to its portability, stick is ideal for welding plates and beams together in hard to reach places.
Due to the solid shielding flux being right at the arc, It’s also practical for exterior structural welding.
Although less common, you can use Stick for welding stainless steel, aluminium, nickel, and copper alloys.
Advantages Of Stick Welding
- Stick welding is practical even when it’s windy or raining
- The equipment required is not very expensive
- Very portable
- It doesn’t need an external shielding gas
- It’s less liable to paint, corrosion and dirt
- It’s easy to change rods for different applications
Disadvantages Of Stick Welding
- Stick welding is slow
- Extra work and time to chip away the slag
- Challenging to weld thinner metals
- You have to replace welding rods more often than other types of welding
- There can be excessive spatter, rough surfaces, and porosity
- Very smokey, dirty, and the fumes are toxic
Alternate Names for Stick Welding
- Arc Welding
- Shielded Metal Arc Welding (SMAW)
- Manual Metal Arc Welding (MMA or MMAW)
- Flux Shielded Arc
Other Types Of Welding?
There are many other types of welding used today, such as:
- Submerged Arc Welding (SAW)
- Energy Beam Welding (EBW)
- Atomic Hydrogen Welding (AHW)
- Plasma Arc Welding.
Quick Look Pros and Cons Table
|MIG welding – Gas Metal Arc Welding (GMAW)
|MIG is excellent for welding large materials quickly.
It is a beginner-friendly welding type.
|MIG welds are not as precise, firm, or clean not as TIG welds.
The workpiece must be free of any scale or rust.
|TIG welding – Gas Tungsten Arc Welding (GTAW)
|TIG is highly precise and versatile, letting you join a broad range of materials.
It is excellent for welding non-ferrous metals.
|TIG is hard to learn, making it slower with longer lead times and higher production costs.
|Stick Welding – Shielded Metal Arc Welding (SMAW)
|Stick welding is versatile, cheap to start and easy to learn. Used on a variety of metal alloys.
|You have to replace consumable electrodes often.
Slag must be removed after welding, making it a slower process.
|Flux Welding – Flux Cored Arc Welding (FCAW)
|Flux welding does not use a shielding gas, which can be used outdoors and in windy conditions, and it can also be used on a variety of metal alloys.
|The filler material is more expensive than other arc welding types, and it also generates more fumes and smoke than different types of arc welding.
|Submerged Arc Welding (SAW)
|Submerged arc welding produces less spatter and lower levels of UV radiation.
Can weld thicker materials very quickly due to high deposition rates
|The weld can only be performed horizontally due to a layer of granular flux covering the weld pool.
Initial costs for equipment are substantially higher due to the level of automation required.
|Energy Beam Welding (EBW)
|Energy beam welding can weld metals with different melting points and conductivities.
It is precise and gives the welder control over the process.
|Welds can bend and crack after the material has cooled.
|Atomic Hydrogen Welding (AHW)
|Atomic hydrogen is able to reach temperatures of up to 4000 °C, which can weld tungsten.
Hydrogen prevents oxidation and contamination of the materials, and this process does not require flux.
|Atomic hydrogen welding is replaced by gas metal arc welding because of inexpensive inert gases.
|An oxy-acetylene torch is lightweight, compact, and quiet.
They can easily cut through ferrous materials up to 8 inches thick.
You can use oxy-acetylene gas to cut, braze, and weld steel.
|Acetylene fuel is more expensive compared to other fuels.
|Plasma Arc Welding
|Plasma welding torches give you great control over the arc and high-quality welds. Welds are clean, smooth, and strong.
|Plasma welding gear is pricey.
It is a more technical welding process and requires more time to train.
Industrial Welding Company
Varlowe Industrial Services specialize in all forms of welding types.
We provide a complete in house welding service for any need.
For more information, please visit our “Welding Services” page or give us a call on 01902 861042.