Shielding gases

Shielding gases are commonly used in several welding processes as MIG (Metal Inert Gas), MAG (Metal Arc Gas) and TIG (Tungsten Inert Gas). Their purpose is to protect the weld area from oxygen, and water vapour. Selecting the right shielding gas can optimise your welding results. Not only do shielding gases protect the finished weld from the effects of oxygen and nitrogen in the atmosphere, they can also have a positive effect on weld metal properties such as strength, corrosion resistance and toughness. In addition, they can optimise the weld bead shape and size as well as the weld porosity and fusion. Linde offers individual shielding gas mixtures like Argon, VARIGON, CORGON, CRONIGON, MISON. - Argon is the common shielding gas, widely used as the base for the more specialized gas mixes. - MISON: Common to all MISON shielding gases is the fact that they contain a carefully weighted additive of nitrogen monoxide which effectively reacts with ozone, forming oxygen and nitrogen dioxide. MISON shielding gas attacks the problem directly at the source, i.e. the ozone disappears as soon as it is formed.

- CORGON is a two-component mixture comprising argon and carbon dioxide. This is a good general-purpose shielding gas for MAG welding of carbon and steel alloys. The amount of spatter and slag islands produced by CORGON are low, making it ideal for applications where post-weld cleaning must be kept to a minimum. - VARIGON is a two-component mixture containing argon and helium. The addition of helium to argon increases the supply of energy to the weld pool, making it more fluid. This, in turn, increases the penetration profile and weld fusion characteristics. - CRONIGON is a two-component mixture comprising argon and carbon dioxide. Its lower oxidation potential reduces the need for aggressive chemical cleaning agents - CRONIGON with helium is a three-component mixture comprising argon, helium and carbon dioxide. The addition of helium into the mixture accelerates welding speeds significantly relative to CRONIGON 2. This translates into vast productivity gains.