Welding gases provide a shield around the welding arc to prevent oxygen, nitrogen and hydrogen (contained in the air around us) from affecting the quality of the weld.
With TIG welding, pure Argon gas will shield most materials, but there are some differences which are illustrated in the table below.
|TIG Welding – What Gas do I Use?|
|Sugested Gas Mixture||Material|
|Carbon Steel||Stainless Steel||Aluminium (Alum’m & Copper Alloys)|
|Argon (100%)||***||** (All)||**|
|Argon/Hydrogen (98/2%)||*** (Austenitic only)|
|Argon/Nitrogen (98/2%)||** (Duplex only)|
The size of gas bottle (and where you buy it from), may be dictated by a number of factors:
Each supplier will often have their own different sized gas bottles and rental agreement (if purchasing gas in larger quantities). It’s important to check the actual volume of gas supplied (under pressure), rather than the size of the gas bottle (cylinder). So how do you compare?
See the article on: How to Buy a Gas Bottle (opens in a new window).
The Argon is connected to the TIG welder through a regulator. The regulator is a valve that screws into the top of the Argon bottle. It allows you to:
The hose between the TIG welder and the Argon bottle is just a small, low volume hose. Hence the regulator provides a means of ‘stepping down’ the gas pressure for the gas supply to the TIG welding set.
A regulator is often supplied with one or two gauges. The first shows the bottle contents, the other will show the pressure of the Argon supplied to the TIG welder.
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