Which gases should you use when using a plasma cutting machine?

September 28, 2023

Plasma cutting comes from plasma welding, which was a popular technique in the 1960s. It was introduced in the 1980s as a complete cutting method. Why has it become so popular? The reason is that plasma cutting does not create metal chips and is very precise when cutting. The first plasma cutting machines were very large and were intended mainly for mass production, due to the repetitive cutting patterns.

Plasma cutting, which is a thermal cutting method, is widely used for cutting or engraving metals . It is one of the most affordable cutting methods that provides high-quality and precise cuts without damaging the material. Although it is a popular metal cutting technique, most of you are not aware of plasma cutting.

Which gas is used for plasma cutting?

The gas used for plasma cutting is usually a mixture of gases. The specific composition may vary depending on the material being cut and the desired cut quality. The primary gases used for plasma cutting are:

1. **Compressed Air:** Compressed air is the most common gas used for plasma cutting. It is readily available, economical, and suitable for cutting a wide range of materials, including mild steel, stainless steel, and aluminum. However, when using compressed air, the cut quality may not be as high as when using other gases.

2. **Nitrogen:** Nitrogen is often used for cutting stainless steel and aluminum because it produces a clean, oxide-free cut. This is especially useful when a high-quality, oxide-free edge is required. Nitrogen can also be used for cutting other materials, but is less common due to its high cost compared to compressed air.

3. **Oxygen:** Oxygen can be used for plasma cutting, but it is usually used for cutting mild steel. When oxygen is used, it reacts with the molten metal to aid in the cutting process. However, it is not suitable for cutting materials such as stainless steel or aluminum, as this can cause oxidation.

4. **Argon-Hydrogen:** A mixture of argon and hydrogen gases is sometimes used for plasma cutting. This gas mixture can produce exceptionally high quality cuts with minimal heat affected zones. It is often used for cutting thin metals and materials that require a very clean and precise edge.

The choice of gas depends on the material being cut, the desired cut quality, and the specific capabilities of the plasma cutting machine. It is important to follow the manufacturer's recommendations and instructions for gas selection to achieve the best results for your specific cutting application.