MIG (Metal Inert Gas) welding is a popular welding process that utilizes a consumable wire electrode to join metal pieces together. The wire acts as both the filler material and the electrode, making MIG welding a versatile and efficient method for various applications. However, selecting the right MIG welding wire is crucial to ensure optimal weld quality and performance.
Selection Guide for MIG Welding Wires
Choosing the appropriate MIG welding wire involves considering several factors, including the type of metal being welded, the welding process, and the desired weld characteristics. Here are some key points to consider when selecting MIG welding wires:
- Metal Type
- Wire Diameter
- Shielding Gas
- Wire Feed Speed
- Quality and Brand.
MIG Welding Wires
The most commonly used MIG Welding wires for Carbon steel, cast steel and low alloy steel are:
ER70S-2 MIG Welding wire
ER70S-2 welding wires are primarily used for single-pass welding of killed, semi-killed, and rimmed steels. These wires contain deoxidants that allow welding on surfaces with rust or dirt, although weld quality may be compromised.
They are commonly used for high-quality, high-toughness welds with the GTAW process and are suitable for single-side, melt-through welding without a protective root shielding gas.
ER70S-3 MIG Welding wire
ER70S-3 welding wires are designed for both single-pass and multi-pass welds. They are widely used in GMAW electrodes and have similar base metal specifications as ER70S-2 wires.
ER70S-4 MIG Welding wire
ER70S-4 welding wires are intended for steel welding applications that require more deoxidation than ER70S-3 wires provide. They have similar base metal specifications as ER70S-2 wires and do not require impact testing.
ER70S-6 MIG Welding wire
ER70S-6 welding wires are suitable for both single-pass and multi-pass welding. They are especially well-suited for sheet metal applications and structural and plate steels with moderate amounts of rust or mill scale.
These wires allow the use of higher current ranges with CO2 or mixtures of argon and oxygen or argon and carbon dioxide as shielding gases.
ER70S-7 MIG Welding wire
ER70S-7 welding wires are intended for single-pass and multi-pass welding. They offer higher travel speeds compared to ER70S-3 wires and provide better wetting action and bead appearance.
Similar to ER70S-6 wires, they can be used with CO2 or mixtures of argon and oxygen or argon and carbon dioxide as shielding gases.
ER70S-8 MIG Welding wire
ER70S-8 electrodes are suitable for both single-pass and multi-pass welding. They are characterized by a stable globular arc, low spatter, good resistance to porosity, and smooth bead shape when used with high current and CO2 shielding gas. They can also be used with mixtures of argon and CO2.
ER70S-G MIG Welding wire
ER70S-G welding wires are classified separately and have specific mechanical property requirements. They can be used for both single and multiple-pass applications, and it is recommended to consult the filler metal supplier for detailed information on their composition, properties, characteristics, and intended use.