Engineering Overview
In abrasive blasting, the nozzle orifice acts as a restricted opening. To maintain a specific **Blasting Pressure (PSI)**, the compressor must deliver a specific **Volume (CFM)** of air. If the compressor cannot meet the CFM demand of the nozzle, the pressure will drop, leading to slower cleaning speeds and wasted media.
CFM vs PSI Demand Chart
| Nozzle Size | 80 PSI (CFM) | 100 PSI (CFM) | 120 PSI (CFM) | Min HP |
|---|---|---|---|---|
| 5 mm (#3) | 45 | 54 | 63 | 15 HP |
| 6.5 mm (#4) | 81 | 94 | 108 | 25 HP |
| 8 mm (#5) | 137 | 161 | 185 | 40 HP |
| 9.5 mm (#6) | 196 | 230 | 264 | 60 HP |
| 11 mm (#7) | 254 | 300 | 346 | 75 HP |
| 12.5 mm (#8) | 338 | 396 | 454 | 100 HP |
*HP requirements based on Rotary Screw performance at 4 CFM per HP.
Technical Selection Guide
Nozzle: 6.5mm (#4)
Comp: APEX-30
Use: Precision / Light Maintenance
Nozzle: 8mm (#5)
Comp: APEX-45
Use: Structural Steel / Fabrication
Nozzle: 9.5mm (#6)
Comp: APEX-75
Use: Shipyards / High-Volume Tanks
Pressure Drop Logic
Every 50ft of 1" blast hose causes a pressure drop of approx 2-3 PSI. Using a **Vertical Air Receiver** near the blast zone acts as a buffer, ensuring the nozzle maintains peak PSI during continuous duty cycles.
The Moisture Threat
High CFM creates high friction heat in the air lines. Without a high-capacity **Moisture Separator**, condensation will form, causing abrasive to damp-clump and stop the technical flow of media.