Using the Proper Cover Gas

When it comes to industrial welding, precision and attention to detail mean everything. Using the proper cover gas for each particular metal being worked is integral to a strong weld and is especially critical in GTAW or GMAW welding processes. With the wrong cover gas, welds will fail and you will be creating an unnecessary safety hazard for both you and your coworkers. Take a few moments to review some of the most important cover gases, how to use them safely and what metals they are meant to shield.

Helium

Since helium possesses high ionization potential, the welds made with this shielding gas are a wide deep bead which is perfect for metals like magnesium, aluminum or copper. For stainless steel welding, a combination of helium, argon and carbon monoxide works very well.

Oxygen

When combined in small quantities with a gas like argon for instance, oxygen improves the stability of the welding arc while simultaneously reducing the surface tension of the metal being welded. It’s important to thoroughly research the correct amount of oxygen to use. Using too much oxygen will result in a brittle weld.

Hydrogen

Stainless steel, nickel and heavier metals should be welded using hydrogen. To prevent oxidization of the metal, hydrogen is typically blended with a small amount of argon. Arc size is reduced while the arc temperature is increased. This helps ensure a strong, penetrating weld.

Always wear the appropriate protective gear when working with any combination of cover gases, especially argon and hydrogen. When preparing to create a weld, ensure you are using the best cover gas for the job. Selecting the best combination of cover gases for different welds will ensure consistency and a strong bond every time.