Standard TIG Welding Gases

Air Products offers a full range of standard shielding gas mixtures
for the TIG welding of all common material
types.Our standard gases are available in traditional cylinder sizes
at 200 bar and 230 bar cylinder pressure. Further information
on cylinder contents, pressures and valve outlet connections can
be found on the Welding and Cutting Gases Cylinder Identification
sheet.

Our Standard shielding gases are named in accordance
with their chemical composition:
     
Hytec argon, hydrogen [Ar, H2
]
Astec argon, helium [Ar, He]
Protec nitrogen, hydrogen [N2, H2]
     
[Note where x = a number
between 0 and 9]

TIG (tungsten inert gas) welding is a high-quality welding technique with a low fusion rate. The arc burns between a tungsten electrode and the workpiece; the electrode does not melt, so it acts only as a current conductor and arc carrier.

For thin sheet metal work, TIG welding can be used without a filler metal.For thicker items or when joining different materials, a filler metal is used in the form of a handheld rod or a wire supplied by a separate feed device, generally currentless.In standard TIG welding the arc is free, but a variant known as plasma welding uses a secondary nozzle to constrict the arc.

The melt, the hot tungsten electrode and the molten end of the filler metal are protected from the atmosphere by an envelope of inert gas. Argon is generally used, although there are quality and productivity advantages in using a mixture of either argon and helium or argon and reduced hydrogen