Gas metal arc welding (GMAW or MIG/MAG)
Introduction
GMAW (MIG)
MIG welding (also referred to as GMAW) stands for “Metal Inert Gas” and refers to a welding process in which a base metal and a filler metal are protected by a jet of inert gas while an electric arc is used to heat the material. The heat source of the arc produces a molten metal, which is supplemented by a continuously fed welding wire. It is one of the most commonly used welding processes and is particularly suitable for welding thin sheets and tubes of stainless steel, aluminium and other alloys.
GMAW (MAG)
MAG welding stands for Metal Active Gas welding and is a type of GMAW (Gas Metal Arc Welding) in which a shielding gas is used to protect the material from oxygen and hydrogen during the welding process. The difference to MIG welding is the shielding gas and the type of welding wire used. Whereas MIG welding uses a pure shielding gas (often argon or helium), MAG welding uses a gas mixture (usually CO2 with argon or helium). MAG welding is particularly suitable for welding low alloy and low carbon steels. It is also a very common type of welding in the automotive and engineering industries.
Areas of application
GMAW welding, also known as MIG or MAG welding, is widely used in many industries due to its versatility and ease of use. It is commonly used in the following industries and applications:
- Automotive: for welding car bodies, exhaust systems and other parts
- Manufacturing: for welding machinery and equipment
- Construction: for welding structural steel, bridges and buildings
- Aerospace: for welding aircraft components and structures
- Fabrication: for welding metal products and components
In addition, GMAW welding is often used for repair and maintenance work, as well as for welding in hard-to-reach areas or in situations where precision is important. It is also widely used for welding non-ferrous metals such as aluminium and copper alloys, and for welding thin sheets, tubes and pipes.
GMAW welding is used in a wide variety of industries and applications where high quality welds are required quickly and efficiently.
Advantages and disadvantages
The advantages of GMAW (MIG/MAG) welding include
- High welding speed and efficiency: GMAW welding can be performed quickly, making it a cost-effective option for high volume production.
- Versatility: GMAW welding can be used on a wide range of materials, including steel, aluminium and stainless steel, and can be used on thin or thick sections.
- High quality welds: GMAW welding produces high quality, consistent welds with minimal spatter and minimal post weld cleaning.
- Easy to use: GMAW welding is relatively easy to learn and use, making it a popular choice for hobbyists and DIY projects.
- High deposition rate: GMAW welding has a high deposition rate and can be used for welding in hard-to-reach areas.
Disadvantages of GMAW welding include
- Limited use outdoors and in windy conditions: GMAW welding requires a shielding gas to protect the weld pool, making it difficult to use in windy conditions or outdoors.
- More expensive equipment: GMAW welding requires specialised equipment, such as a power source and wire feeder, which can be more expensive than other types of welding equipment.
- Limited penetration: GMAW welding typically has less penetration than other welding processes, making it less suitable for welding thick sections of material.
- Limited to thin sheets: GMAW is not suitable for welding thick sheet metal, limiting its use in some industries.
- Not suitable for contaminated or rusty surfaces: GMAW welding requires a clean surface to produce a good quality weld, so it is not suitable for dirty or rusty surfaces.
Overall, GMAW welding is a popular choice for many industries and applications due to its high welding speed, versatility and ease of use. However, it may not be the best choice for all situations, especially in outdoor and windy conditions, and it requires specialised equipment that can be more expensive than other types of welding equipment.