More and more laser cutting machines use compressed air as an assist gas, instead of nitrogen or oxygen for some jobs. The air blows the molten metal out of the kerf and protects the cutting head. But this is not ordinary workshop air: it needs more pressure, and air that is much cleaner and drier.
The three criteria to check
1. Pressure
A typical workshop runs at around 6 to 8 bar. Laser cutting with air can require considerably more. The figure to go by is the one given by the manufacturer of your laser machine: it depends on the model, the cutting head and the thicknesses being cut. The compressor must be able to reach it with a margin.
2. Flow
The flow required also depends on the machine and the nozzle used. It is given in the manufacturer's documentation, in litres per minute or in m³/min. Compare it with the compressor's actual flow at working pressure, not with the maximum flow quoted at low pressure.
3. Air quality
This is the point most often underestimated. The air reaches the optics of the cutting head. The water, particles and traces of oil it carries can foul or damage the protective lens and degrade cut quality. You therefore need:
- a dryer to remove moisture;
- fine filtration to trap particles;
- filtration that captures oil aerosols.
Our guide to compressed air quality under ISO 8573-1 explains how these requirements are expressed as purity classes.
The L series - everything built in
Our L series compressors bring together on one frame a variable speed screw compressor with permanent magnet motor, a 16 bar tank, a refrigerated dryer and precision filtration.
| Model | Power | Pressure | Flow | Tank | Noise level | Dimensions (L × W × H) | Weight |
|---|---|---|---|---|---|---|---|
| L 110 | 11 kW | 8 to 16 bar | 0.8 m³/min | 340 L, 16 bar | 72 ± 3 dB(A) | 1750 × 700 × 1610 mm | 480 kg |
| L 150 | 15 kW | 8 to 16 bar | 1.3 m³/min | 500 L, 16 bar | 72 ± 3 dB(A) | 1800 × 800 × 1710 mm | 690 kg |
| L 220 | 22 kW | 8 to 16 bar | 1.8 m³/min | 500 L, 16 bar | 72 ± 3 dB(A) | 1900 × 900 × 1710 mm | 750 kg |
Air quality is the same on all three models:
| Air treatment | Value |
|---|---|
| Refrigerated dryer | Dew point 3 to 10 °C |
| Particle filtration | Down to 0.01 µm |
| Residual oil | 0.001 ppm |
| Outlet connection | DN15 |
Why not a standard workshop compressor?
| Workshop screw compressor | L series compressor | |
|---|---|---|
| Maximum pressure | 8 to 13 bar depending on the model | 16 bar |
| Air receiver | Pressure rating matched to the compressor | 16 bar |
| Dryer | Depending on the option | Built in |
| Precision filtration | To be added | Built in |
A workshop compressor may be suitable if your laser machine is satisfied with its pressure and you add the necessary air treatment. As soon as the machine needs more than 13 bar, you need a compressor designed for that pressure, with an air receiver and equipment rated for it.
Choosing the model
- Look up in your laser machine's documentation the pressure and flow required for the assist air.
- Choose the model whose flow covers this requirement with a margin.
- If you plan to add a second machine or cut thicker material, go one size up.
Services are carried out at 500 hours, then every 1,500 hours, with a reminder shown by the controller. If you are unsure about sizing, send us your machine's data sheet with a quote request: we will tell you which model suits. To compare with the rest of the range, see the comparison of our screw compressors.