Helium (He) is the second lightest process gas next to hydrogen. Colorless, odorless, tasteless, nontoxic and chemically inert, helium is nonflammable and, when compared with argon, has a high thermal conductivity. Helium-enhanced mixtures are utilized to create an inert gas shield and prevent oxidation during open arc welding of metals such as aluminum, stainless steel, copper and magnesium alloys. The addition of helium generally increases weld pool fluidity and travel speed. Penetration properties will be broader and travel speed is typically increased with the addition of helium to the shielding gas mixture. Use of helium-enhanced mixtures will also lessen the formation of welding ozone when welding on aluminum alloys.


Helium Cylinder Transportation Information

Chemical FormulaHe
Minimum Purity99.995 %
Cylinder CGA Outlet580
680 (greater than 3,000 psig)
CAS Number7440-59-7
UN Number1046
US DOT NameHelium, Compressed
US DOT LabelNonflammable Gas
US DOT Class2.2 Nonflammable Gas

Helium Cylinder Information

Cylinder StyleVolume (ft3/m3)Pressure at 70°F (21C°) (psig/kPa)Part Number
T286/7.942640/18202HE T
K213/5.912200/15168HE K