Pressure generators

We offer a large variety of pressure generators for different purposes and pressure ranges.

We offer:

The Dunze GmbH started manufacturing the worlds first 4 litre, 4000 bar hydroforming pressure intensifier in 1976. Since then we set new standards in the development of hydroforming pressure intensifiers. Our new pressure intensifiers can be supplied with the following – mostly patented – features:

  • Integrated bolt tensioning device: There is no easier and faster method to assemble or disassemble a pressure intensifier.
  • Simply replaceable inner liner: After a longer period of usage, the sealing in touch with the cylinder wall, gets damaged. No honing or special sealings are needed for maintenance of our pressure intensifiers, simply replace the inner liner.
  • Preloaded high-pressure plug: Our plugs are preloaded similarly to a shrink, cracked high-pressure plugs are past.
  • Integrated inlet non-return valve: Same technic as our proven non-return valves, but no extra piping. Space-saving, cost-efficient and easy disassembly.
    Integrated pressure sensor: Normally we supply a pre-assembled pressure sensor for the high-pressure side, no extra fitting needed.
  • Simply adjustable transmission ratio: Adjusting the transmission ratio of our pressure intensifiers is a matter of minutes. Advantages are savings in time and cost, faster running and full usage of the capacity of the pressure intensifier.
  • Integrated position sensor: A standard for Dunze GmbH pressure intensifiers since decades.

Our pressure intensifiers are extremely tough and durable. Sealing service life of many years are not uncommon for our pressure intensifiers.

Catalogue: Hydraulic powered pressure intensifiers for hydroforming

We supply pressure intensifiers for isostatic presses, autofrettage systems and a variety of other purposes. Currently the maximum operation pressure is 14.000 bars and the largest stroke volume supplied was 30 litres.

Our pressure intensifiers can be used for liquids and gases in a continuous or discontinuous operation mode. They are driven by hydraulic power. Upon your request we can also supply the corresponding hydraulic power unit. Usually our pressure intensifiers are designed for a hydraulic power pressure from 250 to 350 bars. The high-pressure part of the pressure intensifier can be separated from the hydraulic power part with a spacer if a contamination cannot be tolerated.
The structure of our pressure intensifiers allows a fast and simple assembly. Four tension rods take the tension in axial direction and ensure a higher operational safety than other systems. Smaller pressure intensifiers can be supplied as a single-direction working variant or with two high-pressure heads for continuous flow.

Catalogue: Hydraulic powered pressure intensifiers for fluids and gases

Pneumatic powered pressure intensifiers are an alternative to smaller hydraulic powered pressure intensifiers or hand spindle pumps. They can be used for liquids and gases for a pressure up to 14.000 bars.

The advantage over the hydraulic powered pressure intensifiers is that there is no hydraulic power aggregate needed and they can be powered with air with a maximum pressure of 7 bar. The air pressure can be adjusted and regulated by a manual precision pressure regulator or an automatic proportional valve. Pneumatic powered pressure intensifiers do not need an electric power supply and are therefore suitable for explosionproof systems.

The advantage over hand spindle pumps is that there is no physical effort and a faster compression. On the other hand, the manual spindle pump can be precisely adjusted to a certain pressure and needs less space. The costs for both types are quite similar.
Multistage systems, meaning several pistons in series connection, allow larger stroke volumes. Parts in contact with the medium are made of stainless steel.
The pressure intensifiers can be supplied with 1, 2, 4, 6 or 8 pistons. The diameters of the plunger are matched to the power drive.

Catalogue: Pneumatic powered pressure intensifiers

Compressed air pumps generate high pressures within a minimum size. The pumps operate on the differential piston principle, i.e. low air pressure is guided on a large piston and moves a small hydraulic piston.
The ratio A x P (area x pressure) of the large piston corresponds, apart from losses, to that of the small piston. Compressed air pumps are supplied in wide ranges with ratios from 5:1 up to 1000:1. In the final position of the differential piston, the air control valve switches, so that an oscillating effect arises. When operating pressure is reached, the pump stops automatically. At a slight pressure drop, it automatically builds up the operating pressure. So, there is no additional pressure control needed.
Compressed air pumps are significantly more cost effective compared to electrically operated high-pressure pumps with the same high flow rate.

All our hydraulic pumps work smoothly and economically for many years when used in accordance with our instructions. All models have a wide working pressure range, in which they work economically. The air pressure can be between 2.5 and 7 bars. At 7 bars, the maximum delivery rate is achieved on all models. Both pressure and capacity can be easily controlled by a pressure controller in the compressed air line.

Our pumps can be supplied for oil, gases, water or other liquids.

For the compression of gases or the pumping of certain liquids a medium separator can be used. A medium separator is a cylinder with a piston and is driven by oil or water. On both sides of the piston the same pressure is applied, therefore the sealing is only used for sealing and accordingly has a long life span.

For continuous flow we also offer systems with two or three medium separators. We supply separators for pressures up to 14,000 bar and with a stroke volume from 0,1 – 100l.

Spindle pumps are suitable for generating high static pressures in small volumes. Our spindle pumps cover all pressure ranging up to 14.000 bars. With hand spindle pumps exact pressures can be achieved with a high precision and without a stick-slip effect. The hand pump is operated by four sturdy handles. Many customs operate our spindle pumps since decades without sealing replacement.

Medium contacting parts are made of stainless steel. These spindle pumps are also available with a stepper motor drive, pneumatic drive or as a functional system.

Catalogue: Hand spindle pumps

Spindle pumps are suitable for generating high static pressures in small volumes. Our spindle pumps cover all pressure ranges up to 14.000 bars. With motor spindle pumps exact pressures can be achieved faintly with a high precision and without a stick-slip effect. The medium contacting parts are made of stainless steel.

Catalogue: Motor spindle pumps

We supply simple hand pumps for pressures up to 6.000 bars. Possible mediums are all non-aggressive liquids, i.e. water, oil or water with glycol.

We supply hydraulic handpumps for pressure up to 2.800 bars as a single-stage or a double-stage version.

We supply motor powered, pneumatic powered and hydraulic powered diaphragm compressors with pressures up to 3.000 bars.