Oxygen : Used in welding to promote combustion and increase flame temperature. used for plasma cutting and gouging.
Acetylene : Used in welding for its high temperature flame and is often combined with oxygen to produce a hot flame for welding and cutting.
Argon : Used as a shielding gas in gas tungsten arc welding (GTAW) or TIG welding to prevent oxidation of the weld and improve its quality.
Carbon Dioxide : Used as a shielding gas in gas metal arc welding (GMAW) or MIG welding to protect the weld pool from atmospheric contamination.
Helium : Used as a shielding gas in gas tungsten arc welding (GTAW) or TIG welding for welding non-ferrous metals such as aluminium and copper.
Nitrogen : Used in welding for purging and to prevent the oxidation of metals during heat treatment.
Hydrogen : Used for welding stainless steel, titanium and other reactive metals It is also used for heat treating and stress relieving.