# Hydraulics calculator / calculate hydraulics

## Hydraulik pumps

### Measurements and units used

 Drive torque T Nm Differential pressure ∆p bar Rotation speed n min-1 Geometr. displacement volumeThe volume of liquid in cm³ in a pump or motor displaced by the upward stroke or other cycle during a rotation of the drive shaft. per rotation Vg cm3 Power P kW Volume flow rate qv L/min Volumetric efficiency ηvol 0,9 - 0,95 Mechanical hydraulicThe use of liquids to transmit force and energy. efficiency ηmh 0,9 - 0,95 Total efficiency (ηt = ηvol * ηmh) ηt 0,8 - 0,85

### qv = volume flow rate in in L/min

 Vg = cm3 n = min-1 ηv = (Standard value ca. 0.9–0.95)

 P = kW Δp = bar ηt = (Standard value ca. 0.8–0.85)

### Vg = geometric displacement volume cm³/U

 qv = L/min n = min-1 ηv = (Standard value ca. 0.9–0.95)

 T = Nm Δp = bar ηmh = (Standard value ca. 0.9–0.95)

### n = rotation speed in min-1

 qv = L/min Vg = cm3/revolution ηv = (Standard value ca. 0.9–0.95)

 P = kW T = Nm

### T = torque in Nm

 Vg = cm3 Δp = bar ηmh = (Standard value ca. 0.9–0.95)

 P = kW n = min-1

### ∆p = differential pressure in bar

 T = Nm ηmh = (Standard value ca. 0.9–0.95) Vg = cm3

 P = kW qv = L/min ηt = (Standard value ca. 0.8–0.85)

### P = power in kW

 T = Nm n = min-1

 qv = L/min Δp = bar ηt = (Standard value ca. 0.8–0.85)

## Gear pump

### Measurements and units used

 Geometr. displacement volume per rotation Vg cm3 Gear pump diameter D cm Length of bore in pump casing L cm Gear width W cm Conveyed volume calculation for a gear pumpThe oil volume enclosed in the gap between teeth is conveyed from the intake to the discharge side of the pump by the turning of the gear, displaced to the contact point of the wheel and forced into the pressure connection. per rotation (cm³)

 D = cm L = cm W = cm

## Hydraulic motors

### Measurements and units used

 Drive torque T Nm Differential pressure ∆p bar Rotation speed n min-1 Geometr. displacement volume per rotation Vg cm3 Power P kW Volume flow rate qv L/min Volumetric efficiency ηvol 0,9 - 0,95 Mechanical hydraulic efficiency ηmh 0,9 - 0,95 Total efficiency (ηt = ηvol * ηmh) ηt 0,8 - 0,85

### q v = volume flow rate in in L/min

 Vg = cm3 n = min-1 ηv = (Standard value ca. 0.9–0.95)

 P = kW Δp = bar ηt = (Standard value ca. 0.8–0.85)

### V g = geometric displacement volume cm³/U

 qv = L/min n = min-1 ηv = (Standard value ca. 0.9–0.95)

 T = Nm Δp = bar ηmh = (Standard value ca. 0.9–0.95)

### n = rotation speed in min-1

 qv = L/min/revolution ηv = (Standard value ca. 0.9–0.95) Vg = cm3

 P = kW T = Nm

### T = torque in Nm

 Vg = cm3 Δp = bar ηmh = (Standard value ca. 0.9–0.95)

 P = kW n = min-1

### ∆p = differential pressure in bar

 T = Nm Vg = cm3 ηmh = (Standard value ca. 0.9–0.95)

 P = kW qv = L/min/revolution ηt = (Standard value ca. 0.8–0.85)

### P = power in kW

 T = Nm n = min-1

 Δp = bar qv = L/min ηt = (Standard value ca. 0.8–0.85)

### Calculate hydraulics quickly...

HK Hydraulik GmbH offers all professionals and interested parties ready-made calculators for the most important hydraulic calculations.

Until now, to calculate the Volume flow rate or conveyed volume of a gear pump, technicians had to look up the formulas, pick up a calculator, enter the calculation according to the formula, and recalculate it again to check as a precaution. This could take a whole 15 minutes.

Now you just have to enter the values you know / have calculated / measured into the relevant calculator module, and you get your result straight away.

Please note: when we suggest standard values, this gives you a very close approximation that is good enough for general use. You can of course also enter the actual values instead of the standard values.