We often hear it: "I'm looking for a compressor for soft blasting, 2 to 8 bar, with a flow of 300 to 2,000 L/min." That is exactly the right way to frame it. In soft blasting, motor power alone is not enough to choose: what matters is the air flow the compressor holds at working pressure, for hours on end.
1. Start from the nozzle
A soft blasting machine's air consumption depends first on the nozzle diameter. A small finishing nozzle uses a few hundred litres per minute; a large stripping nozzle can exceed 2,000 L/min. The exact figure is in your machine's documentation, nozzle by nozzle.
Note the consumption of the largest nozzle you will use, at the highest pressure you will need. That is what sizes the compressor.
2. Add a margin
Two reasons to add a margin:
- The nozzle wears. The abrasive gradually widens its bore, and a worn nozzle uses noticeably more air than a new one.
- The compressor should not run at 100% all the time. A screw compressor handles continuous duty, but a flow reserve keeps the pressure steady at the nozzle.
A margin of about 25% is a good starting point. For a need of 1,800 L/min, aim for a compressor that delivers at least 2,200 L/min at working pressure.
3. Read the flow at the right pressure
A screw compressor delivers less air as pressure rises. The K 150, for example, delivers 2.2 m³/min at 8 bar, 2.0 m³/min at 10 bar and 1.6 m³/min at 13 bar. For soft blasting, an 8 bar version is usually enough and gives the best flow. Our flow and pressure converter switches from m³/min to L/min if your machine's data sheet uses another unit.
4. Plan for dry air
Damp abrasive sticks, blocks the metering valve and comes out in bursts. A soft blasting compressor must be followed by a refrigerated dryer and filtration. 4-in-1 models include them as standard. We cover this in soft blasting: why the air must be dry.
Example choices
| Need at 8 bar (margin included) | Recommended model |
|---|---|
| Up to 1,700 L/min | K 110, 11 kW 4-in-1 screw compressor |
| Up to 2,200 L/min | K 150, 15 kW 4-in-1 screw compressor |
| Same flow, dryer already installed | S 150, 15 kW standalone screw compressor |
| Beyond that | Industrial project, quoted |
What about the power supply?
The 11 and 15 kW screw compressors run on 380 V three-phase. Check your installation before buying: this point, more than the compressor itself, often decides where the blasting station goes.
Torn between two models? Send us your blasting machine's data sheet with a quote request and we will check the flow with you.
For your trade: Compressor for soft blasting, Compressor for metalwork and fabrication shops, Compressor for joinery workshops.