How to choose the right gas to cut carbon steel

Oxygen is usually been chosen in laser cutting carbon steel work. With the continuous progress and breakthrough of high power laser cutting technology, nitrogen and air has become a strong auxiliary of carbon steel processing work.  Flexible choice of nitrogen, oxygen, and air according to different application requirements can not only improve cutting efficiency, but also reduce end-processing costs.  

Reasons for choosing different kinds of gases:

1. For any thickness of carbon steel, there is a limit speed for cutting using oxygen, even if the laser power increases, cutting speed remains the same.
   

2. High power laser cutting in thin carbon steel with oxygen, to prevent the power is too high caused by cutting over burning, must reduce the power.

3. 10,000 watt laser using oxygen to cut thin carbon steel has no speed advantage, but it increases processing costs.

Figure 1  Cutting efficiency

Concluded from the above test data:

1. The efficiency of applying 10KW cutting machine using air to cut carbon steel 6-20mm thick plates, has increased 600%-10% than oxygen.

2. The efficiency of applying 10KW cutting machine using air to cut carbon steel 6-20mm thick plates, has increased 27%-8% than nitrogen.

Figure 2  Cutting cost

Concluded from the above test data:

1. For carbon steel thickness between 6 to 16mm, the processing costs of applying 10KW cutting machine is air < nitrogen < oxygen.

2. For carbon steel thickness between 18 to 20mm,  the processing costs of applying 10KW cutting machine is air < oxygen < nitrogen.

Figure 3  Cutting effect

Concluded from the above test data:

1. 10000 watt laser cutting machine to process carbon steel plates between 6 to 16mm, the cost of using air is less than oxygen .

2. 10000 watt laser cutting machine to process carbon steel plates 22 to 45mm, the use of nitrogen and air to cut causes serious hanging slag, and there’s no processing cost efficiency as well. As a result, it is better to use oxygen for cutting, if cost efficiency is needed.