How to choose the right welding gas for your application



Many common welding processes such as MIG, TIG and Metal-Core Arc Welding all require an external shielding gas to function correctly.



A shielding gas essentially protects a weld from exposure to nitrogen, oxygen and hydrogen present in the atmosphere.



These elements can react with the weld pool and cause issues such as porosity and excessive spatter.



Conversely, when Oxy-Acetylene cutting, a gas or fuel is required to penetrate and cut through material.



So regardless of whether you’re welding or cutting, it’s more than likely you’ll need to use some form of gas.   



But which one do you need? Here’s a snapshot of some of the common gases used in welding.




Gas Bottles



WELDING GAS GUIDE – COMMON APPLICATIONS



Argon (100%)

    • The most widely used Inert Gas
    • Used for TIG Welding, MIG Welding – Stainless Steel & Aluminium
    • Nickel, copper, aluminum, titanium, and magnesium alloyed base materials use 100% Argon shielding

Argon + Oxygen

    • Oxygen, in small additions (1-5%), provides good arc stability and excellent weld bead appearance.

    • Both stainless steel and carbon steel benefit from the use of argon/oxygen blends.

Argon + CO2

    • Used for MIG Welding of carbon steel

    • Provides increased arc stability and overall weld quality than pure CO2.

Argon + Oxygen + Carbon Dioxide

    • MIG Welding of Mild Steel

    • Higher Inert Gas Component reduces spatter

Carbon Dioxide (CO2)

    • Only reactive gas which can be used on its own (without an inert gas)

    • CO2 is used in MIG Welding and is the least expensive shielding gas

    • Pure CO2 provides deep weld penetration for thicker material such as carbon steel & low-alloy steel.

    • Provides a less stable arc and produced more spatter when welding.

Gas Bottles



Nitrogen (N2)

    • Used as a shielding or assist gas for plasma cutting aluminium or stainless steel.

    • Applicable as an assist gas for laser cutting.

    • Multi-purpose gas which can be used for tyre inflation, purging air conditioning systems and as an inert gas for food preservation.

Oxygen

    • Used with LPG, Acetylene or Mappgas for cutting or welding.

    • Highly effective when combined with Argon for welding steel & stainless.

Acetylene Gas

    • Acetylene is a flammable, colourless gas which is the hottest and most efficient of all fuel gases.

    • Typical applications include welding, Oxy-acetylene cutting, flame heating, flame gouging, spot-heating, brazing & carbon cutting.

    • Safe to use underground - lighter than air, low ignition energy and low moisture in the flame.