Metal inert gas (MIG) welding is a welding technique that uses heat and electricity to fuse parts together. Fast and efficient, it’s become one of the most popular types of welding processes used in modern metal fabrication. Read on to find out more about what MIG welding is, how it works, and the potential advantages and disadvantages.
Are you looking for MIG welding services in Wiltshire? Contact our team today to request a free quote or discuss how we can help meet your welding needs.
What’s on this page
- What is MIG welding?
- How does MIG welding work?
- What’s the difference between MIG and TIG welding?
- What are the advantages of MIG welding?
- The disadvantages of MIG welding
- MIG welding services in Wiltshire and beyond
What is MIG welding?
MIG welding is an example of gas metal arc welding, a technique in which two metals are joined using a consumable wire electrode. As the base metals melt, they create a weld pool which then fuses the parts as it cools and solidifies. The welding gun also feeds a shielding gas along the electrode to prevent the weld from being contaminated by the surrounding air.
MIG welding first became popular in the late 1940s, when it was primarily used as a tool for welding aluminium and other non-ferrous metals. Favoured for its versatility, ease of use, speed and cost-effectiveness, it’s no wonder the technique is the most common industrial welding process used today.
MIG welding is just one of several welding techniques; other common types include TIG welding, spot welding and stud welding. You can read more about the different types of welding processes on our website.
How does MIG welding work?
MIG welding works by using electricity to create an arc (short circuit) between an electrode wire (a positive anode) and the workpiece metal (a negative cathode). The arc melts the electrode wire to create the weld. The weld pool then cools and solidifies to form a new piece of fused metal.
At the same time, a shielding gas (typically argon or carbon dioxide) is fed along the same supply line to protect the weld puddle from being contaminated by the surrounding air. Without this protection, the weld pool would react with the elements in the air (oxygen, hydrogen and nitrogen), potentially reducing the quality of the weld. The shielding gas also has the added benefit of cooling the welding gun.
What’s the difference between MIG and TIG welding?
The terms MIG welding and TIG welding are often used interchangeably, and while there are similarities, there are also some key differences.
As sub-types of gas metal arc welding, both MIG and TIG welding use an arc to create the weld. However, whereas MIG welding uses a consumable wire electrode, the TIG welding process uses a non-consumable tungsten electrode alongside a separate consumable filler material.
Thanks to the continuous feed, the MIG process is much faster than TIG welding. It’s also easier to learn and perform. That said, TIG welding offers greater precision and control and tends to be better for joining thinner metals.
What are the advantages of MIG welding?
From speed and versatility to quality and ease of use, it’s easy to see why MIG welding is the most popular welding technique used in metal fabrication today. Learn more about the benefits of MIG welding below.
- Fast – MIG welding tends to be much faster than other welding techniques thanks to the continuously-fed electrode wire, which minimises the amount of stopping and starting that’s required
- Versatile – MIG welding is suitable for joining a range of different metals and alloys in a variety of thicknesses
- High deposition rate – As MIG welding enables ‘long weld passes’, more metal can be deposited with each pass. This also means fewer passes are required to weld a large joint, saving time and increasing productivity
- Weld quality – Thanks to its simplicity and excellent weld visibility, it’s possible to achieve high-quality welds quickly and efficiently
- Easy to learn – Its ease of operation makes MIG welding relatively easy to learn compared to other techniques
- Can be automated – The MIG welding process can be easily automated through the use of a robotic welding arm, making it possible to achieve even greater results and consistency
- Clean – Unlike traditional stick welding processes, MIG welding doesn’t use flux or create messy slag. It also produces less weld splatter, making the clean-up process that much easier
- High productivity – The benefits outlined above, such as speed, high deposition and automation, mean MIG welding tends to be more productive than other techniques like TIG welding or stick welding.
The disadvantages of MIG welding
Although MIG welding undoubtedly has many advantages, there are a few disadvantages to bear in mind.
- Limited positions – The fluidity of the weld puddle and the high heat input mean MIG welding is usually unsuitable for vertical or overhead welding
- Unsuitable for thick materials – While MIG welding works well with thin metals, it’s not really suitable for thicker metals that require a more solid weld
- Risk of burn-through – The constant voltage output means there’s a greater risk of burn-through (when the weld metal penetrates completely through the base material)
- Higher set-up cost – Modern MIG welding machines tend to cost more than other types of welding equipment.
MIG welding services in Wiltshire and beyond
As specialists in MIG welding, we can manufacture components and welded assemblies of various sizes and levels of complexity. Based in Wiltshire, our modern factory has fully equipped welding bays and a state-of-the-art robotic arm that allows us to complete large volume welding jobs quickly and accurately.
With decades of experience behind us, we’re able to weld an extensive range of ferrous and non-ferrous materials including carbon steel, stainless steel and aluminium. In addition to our MIG welding service, we also have full facilities for TIG welding, spot welding and stud welding.
Knees Engineering is located in Trowbridge, Wiltshire, but we work with businesses from across the UK.
If you’re looking for an experienced metal fabricator or require MIG welding services in Wiltshire or beyond, give us a call to discuss your requirements.