Product range

Hydro-pneumatic pumps

Pneumatically-operated pumps to generate hydraulic pressure

for single and double acting cylinders

flow rate: 0.85 .. 1.5 l/min
max. operating pressure: 500 bar
max. air pressure 4.5 .. 5 bar
reservoir volume: approx. 2.5 .. 4.0 l

Series Data sheet Technical data
D8.600 Hydro-pneumatic pump units


max. operating pressure 500 bar

flow rate: 1.5 l/min
min. operating pressure: 100 bar
max. air pressure 4.5 bar
min. control pressure for pneumatic valve 3 bar
max. air consumption 1200 l/min
intensification ratio: 1:108
reservoir volume: approx. 4.0 l
usable oil volume: approx. 1.8 l
hydraulic connection: G 1/4

D8.602 Hydro-pneumatic pump units


for single and double acting cylinders, max. operating pressure 500 bar

flow rate: 0.85 l/min
min. operating pressure: 50 bar
max. air pressure: 5 bar
max. air consumption 400 l/min
intensification ratio: 1:100
reservoir volume: approx. 2.5 l
usable oil volume: approx. 2.1 l
hydraulic connection: G 1/4

figure 1: hydro-pneumatic pump D8.600

figure 2: hydro-pneumatic pump unit D8.602 - single-acting version
figure 3: hydro-pneumatic pump unit D8.602 - double-acting version

Hydro-pneumatic pumps D8.600 (figure 1)

The hydraulic clamping pump is particularly suitable for small to medium-sized clamping and assembly fixtures with single-acting cylinders, which operate primarily by intermittence (pressure build up and pressure holding).

The tandem plunger pump is built into the oil reservoir in a space-saving manner. It operates with oscillating movements and automatic stroke reversing control by a pilot-operated 4/2 directional control valve. The stroke frequency and thereby the flow rate depend on air pressure and hydraulic counter pressure.

Control variants

Manually-operated 3/2 directional control valve
This valve is equipped with a turning handle for direct operation at the power unit.

Pneumatically-operated 3/2 directional control valve
This valve is mounted on the power unit allowing for pneumatic remote control, which, however, requires an additional pilot valve (accessory). According to the length of the pneumatic piping between both valves, there is a longer or shorter time delay for the clamping and unclamping operation.

Without valve (for remote control)
This version is designed for external valve controls connected with a pressure and a return line each. The pump unit maintains constant the adjusted pressure.
Under no circumstances a valve for unpressurised cycles must be used, since the pump is only suited for intermittent cycles.

Hydro-pneumatic pump units D8.602 (figure 2-3)

The hydro-pneumatic pump unit is particularly suitable for smaller hydraulic clamping and assembly fixtures with single or double-acting hydraulic elements.

Single-acting version (figure 2)
The hydro-pneumatic pump unit is manually operated. Only by operating the pedal the fixture will be clamped or unclamped. The pump delivers oil as long as the desired operating pressure is obtained. Air pressure is adjusted by a pneumatic service unit. Oil pressure is maintained by an integrated check valve. The pump does not automatically supply oil in case of leaks!

Double-acting version (figure 3)
By pushing the pedal, the connected double-acting hydraulic cylinders are extended or retracted according to the position of the manual 4/3 directional control valve. The pedal has to be pushed as long as the cylinders are in its final position and the desired oil pressure is obtained. After release of the pedal, the pump does not re-deliver in case of pressure drop on the oil side! The pedal can be locked by the laterally-arranged pin with the description “PUSH INTO LOCK”, thereby the pump is continuously supplied with air. In this case the cylinders are exclusively activated by the 4/3 directional manual control valve. Small leaks are compensated by the pump and the oil pressure is maintained constantly.

Important note
For permanent industrial use we recommend the hydro-pneumatic pump as per data sheet D8.600.


for hydro-pneumatic pump unit D8.600

  • Handle
  • Cover
  • Accessory for remote control

data sheet D8.600

For hydro-pneumatic pump unit D8.602

  • service unit
  • pressure gauge
  • pressure gauge union

data sheet D8.602