Sandblasting is one of the easiest applications to undersize because nozzle airflow rises quickly with nozzle diameter and pressure. Always size from the actual nozzle chart or blasting-equipment data and allow margin for losses and wear.
Key points
- Nozzle size strongly affects airflow demand
- Worn nozzles can increase air consumption
- Hose losses matter over long runs
- Moisture management can affect blasting quality
Nozzle size drives blasting demand
Abrasive-blast nozzles are continuous air consumers. Published reference data shows a single nozzle can consume from roughly 80 CFM into the hundreds of CFM depending on diameter and pressure. Nozzle wear can also increase demand.
For productive blasting, size from the nozzle manufacturer chart, then allow for breathing-air or ancillary consumers if they share the compressor, hose pressure drop and a sensible operating margin. Moisture control may also be important.
How to specify the job
Start with the equipment or process that will consume the air. Record the number of tools that may run at the same time, each tool's required airflow, and the highest operating pressure. For industrial temporary-air jobs, also note required air quality, duty cycle, connection size and whether the process can tolerate interruption.
Airflow, pressure and operating margin
Compressor capacity is usually described by airflow and pressure. In Australia you will commonly see airflow in CFM or m³/min and pressure in PSI or bar. The compressor must meet both requirements at the point of use. Long hose runs, fittings, filters and simultaneous demand can reduce effective performance, so a practical sizing margin is useful.
What to ask the hire supplier
Machine
Confirm rated free-air delivery, working pressure, fuel or electrical requirements and whether the exact model may vary.
Accessories
Ask about hoses, manifolds, aftercoolers, dryers, filtration, receivers, fittings and any tool-specific accessories.
Logistics
Confirm towing or delivery, access, placement, refuelling, collection, operating hours and any site induction requirements.
Safety
Follow the supplier's risk assessment and operating manual. Verify hose, coupling and accessory pressure ratings.
Use the sizing calculator
If your application is based on pneumatic tools, our calculator can total approximate airflow and suggest a compressor class. It is a planning tool only; final selection should be confirmed against the actual equipment specifications.
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