In plasma cutting, the most commonly used gases include: compressed air, oxygen, nitrogen, and an argon/hydrogen mixture. Various combinations of each gas may be used as either the primary plasma cutting gas or secondary assist gas to cut different types of material.
Compressed air is the most commonly used gas in plasma cutting. It can be used as both the plasma cutting gas as well as the assist gas to cut with air, nitrogen, and oxygen. The versatility of this gas means it works relatively well for most cutting applications with material thicknesses less than 1”. Compressed air is mostly suitable for low-current cutting applications in which material thickness ranges from gauge to ½”. Cutting with compressed air leaves an oxidized cutting surface similar to when cutting with oxygen.
Oxygen is most frequently used as a plasma gas for cutting carbon steel as it yields high-quality cuts on material thicknesses ranging from gauge to more than 1¼” material. Oxygen can be used as a plasma gas to cut aluminum and stainless steel, but only occasionally as it produces a rough-textured cut edge (with decreased weldability) needing a secondary process.
Nitrogen is commonly used as both a plasma cutting gas and assist gas to nitrogen, oxygen, an argon/hydrogen. Nitrogen produces high-quality cuts on virtually every type of metal. It is mostly suitable for high-current applications in which metal thicknesses are usually between 2” and 3”
The argon/hydrogen mixture is a plasma gas used for cutting stainless steel and aluminum when optimal cut quality is desired. This combination is required for mechanized cutting of any material thicker than 3”.
NOTE* The MultiCam V-Series Plasma uses only compressed air, whereas the 1000-Series Plasma, 3000-Series Plasma and 6000-Series Plasma are compatible with all of the gases mentioned above.