Sizing Tool
Pump Sizing Calculator
Enter your application requirements to find the right NAPCO rotary gear pump. Results are based on tested performance data with water (SG 1.0) at ambient conditions.
Application Requirements
NAPCO pumps deliver 60–158 GPM depending on model and pressure
Maximum rated pressure: 100 PSI
Corrosive or food-grade applications require stainless steel
This calculator provides estimates based on tested water performance data. Higher viscosity fluids may require lower RPM. For application-specific sizing with fluids other than water, contact NAPCO engineering.
Recommended Pumps
Enter your requirements and click "Find My Pump" to see recommendations.
Performance Reference Data
Tested with water (specific gravity 1.0) at ambient conditions. Higher viscosity liquids may require lower pump RPM.
2″ Pump (PA200S / PA200C) — 190 RPM
| PSI | GPM | Brake HP |
|---|---|---|
| 10 | 69 | 0.65 |
| 30 | 65 | 1.8 |
| 50 | 64 | 3.2 |
| 70 | 62 | 4.0 |
| 100 | 60 | 5.7 |
3″ Pump (PA300S / PA300C) — 280 RPM
| PSI | GPM | Brake HP |
|---|---|---|
| 10 | 158 | 1.5 |
| 30 | 147 | 4.2 |
| 50 | 145 | 6.9 |
| 70 | 142 | 9.4 |
| 100 | 140 | 13.4 |
For detailed engineering specifications, see the full engineering data page. For sizing guidance with non-water fluids, read our pump sizing guide.