How It Works
Motor Speed Formula
Hydraulic motor speed depends on flow rate and displacement:
RPM = (Q × 231) / (D × eff_v)
- Q = Flow rate (GPM)
- 231 = in^3 per gallon
- D = Displacement (in^3/rev)
- eff_v = Volumetric efficiency (decimal)
Motor Torque
T = (P × D × eff_m) / (2 × pi)
where P = pressure drop across motor (psi), eff_m = mechanical efficiency.
Motor Horsepower
HP = (T × RPM) / 63025
or equivalently: HP = (P × Q) / 1714
Motor Speed Calculator
Calculate RPM, torque, and horsepower for hydraulic motors from displacement, flow, and pressure.
Motor Speed
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RPM
Motor Results
Motor Speed--
Output Torque--
Output Horsepower--
Theoretical Speed--
Theoretical Torque--
Input HP (hydraulic)--
Overall Efficiency--
Common Motor Types
| Type | Disp Range | Speed | Efficiency |
|---|---|---|---|
| Gear | 0.5-10 in^3 | 500-3000 | 80-90% |
| Vane | 1-15 in^3 | 500-2500 | 85-92% |
| Piston (axial) | 1-60 in^3 | 500-4000 | 90-97% |
| Gerotor | 2-50 in^3 | 50-800 | 80-90% |