The auxiliary gas used by laser cutting machine to process different materials is different. The pressure and requirements of auxiliary gas are different with different cutting thickness. In terms of cost, the oxygen used for cutting carbon steel is relatively cheap, and the amount of nitrogen used for cutting carbon steel is large. The thicker the stainless steel, the higher the requirement for the amount and purity of nitrogen, and the higher the cost.

The auxiliary gas of laser cutting machine is mainly used in:

1. Laser gas (gas used to generate laser in the laser generator)

2. Compressed air (generally used to protect optical path, and some manufacturers also use it as protective gas)

3. Auxiliary gas

The purity of oxygen used for cutting carbon steel is generally 99.5% or higher. Its main function is to support combustion and blow off the cutting slag. The pressure and flow rate are different from each laser cutting machine manufacturer, which is inseparable from the size of cutting nozzle and the thickness of cutting material plate. The pressure is generally required to be 0.3-0.8Mpa, and the cutting tip is generally 0.02-0.05Mpa. The flow is hard to say. For example, when cutting 22mm carbon steel, the flow of some manufacturers should reach 10M3/h (including oxygen for protection of double-layer cutting nozzle)

Nitrogen shall be used to cut stainless steel. Its function is to prevent oxidation reaction and blow off slag. There are high requirements for nitrogen purity (especially for stainless steel with a diameter of more than 8mm, which is required to reach 99.999% purity). The pressure requirement is relatively high, which generally requires more than 1Mpa. For stainless steel with a diameter of more than 12mm or thicker than 25mm, the pressure requirement is higher, which is more than 2Mpa or higher. The flow rate varies according to the model of cutting nozzle, but it is large, For example, cutting 12mm stainless steel requires some manufacturers to cut 150m3/h and 3mm stainless steel, and the flow rate is less than 50m3/h.