Abrasive Blasting, Shot Peening & Surface Prep calculator
Compressor Air Demand Calculator
Compressor shortfalls cause pressure drop, slow cutting, and unstable surface profile. This calculator converts expected nozzle air volume over the job into an average CFM demand so you can compare the requirement with available compressor capacity and hose losses.
What this calculator does
- Estimate effective compressor CFM demand from nozzle air volume, blast runtime, and simultaneous blasting load.
- you are deciding whether the available compressor package can hold blast pressure for the nozzles in service
- Returns the average CFM the compressor system must sustain for the planned nozzle load.
Formula used
- Raw demand = nozzle air volume ÷ blast runtime
- Effective demand = raw demand × simultaneous nozzle load
Inputs explained
- Nozzle air volume: Nozzle CFM at pressure × number of nozzles × planned blast hours.
- Blast runtime: Hours over which the air volume is consumed.
- Simultaneous nozzle load: Use 100% when all nozzles are open continuously.
How to use the result
- Use it before mobilizing compressors, adding another nozzle, or troubleshooting low blast pressure.
- Always check nozzle charts, hose size, moisture control, altitude, and compressor derating; this calculator does not replace a pneumatic sizing review.
Common questions
- Where do I get nozzle CFM? Use the nozzle manufacturer's chart for bore size and blast pressure, then multiply by nozzles and hours to get cfm-hours.
- Why include simultaneous nozzle load? Deadman cycling, pot refills, and repositioning reduce average demand, but critical pressure checks should still consider peak all-nozzle demand.
- Can this size hose or piping? No. Use the result as compressor demand, then check hose ID, couplings, moisture separator, and pressure drop separately.
- What decision does the result support? Compare effective and peak demand to compressor free air delivery before adding nozzles or promising a faster blast schedule.
Last reviewed 2026-05-12.