Paritian

Mechanics

Hydraulic Motor Torque Calculator

Torque, shaft speed and power of a hydraulic motor from pressure, displacement and flow.

Results

Torque 210.85 N·m
Rotational speed 500 rpm
Power 11.040 kW

What this tool does

In a hydraulic drive, pressure sets the torque and flow sets the speed, and the two are almost independent of each other. That is what makes hydraulics so useful for heavy machinery: full torque is available from zero rpm.

Formula

M = p × V ÷ (2π) × η

Variables

SymbolMeaningUnit
pPressurebar
vDisplacement per revolutioncm³/rev
efEfficiency%
qFlow rateL/min
MTorqueN·m
NRotational speedrpm
PWPowerkW

Worked example

  • Pressure180 bar
  • Displacement per revolution80 cm³/rev
  • Efficiency92 %
  • Flow rate40 L/min
  • Torque210.85 N·m
  • Rotational speed500 rpm
  • Power11.040 kW

Limitations

  • The formula assumes ideal conditions: no friction losses, no air resistance and no efficiency losses unless you enter them.
  • For work that must comply with a standard or be signed off, check the result against the applicable code and have it reviewed by a qualified engineer.