Rotary vanes

Rotary vanes

Vanes create pressure in vacuum pumps

The primary purpose of a vacuum pump is to pump out air under high pressure to create a vacuum. Rotary vanes play a decisive role here, as they contribute to compressing the air inside the vacuum pump.

Rotary vane pumps are designed with an asymmetrical interior divided into several chambers with different sizes because of the asymmetrical construction. The vanes are the movable dividers between the chambers. When the vanes are rotating with a lot of force inside the pump, the asymmetrical construction with its differently sized chambers creates a pressure increase inside the pump, putting the compressed air under high pressure. When the air is blown out of the vacuum pump under high pressure, the vacuum effect is achieved at the inlet.

It is crucial for producing high-quality vacuum pumps that the vanes completely shut off the air between each chamber, and this is something which requires very specific materials.

Narrow tolerances and resistance – a necessity for rotary vanes

Rotary vanes can only shut off the air properly if made with tolerances that are as tight as possible. Specific requirements on the material used for the vanes are necessary to achieve this degree of tolerance and precision systematically, and it is also necessary that experts machine the material using special machining tools.

Since the pump vanes are exposed to high continual forces, as well as chemicals and high temperatures, they also need to be extremely resistant. If the strength of the material were insufficient, the vanes would be unable to retain their shape, causing the effect of the vacuum pump to deteriorate significantly or completely.

Composite that meets the many requirements to pump vanes

By using G-Etronax for the pump vanes, both the exact tolerances and extreme strength can be achieved. G-Etronax is our glass-based composite material, which is generally very resistant and is available in a vast number of different qualities. We recommend that only special grades out of our G-Etronax range are used for the production of rotary  vanes, as they  have a high chemical resistance and amazing mechanical properties, even in conditions with continual exposure and high temperature.

However, G-Etronax is particularly distinguished by retaining its shape to an extreme degree and being a stable material with a long service life under the most demanding conditions. One property to highlight is the very low thermal/length expansion coefficient of G-Etronax, whereby the material retains its valuable flatness, even when exposed to high temperatures, varying loads and chemicals.

Explore the many properties of our wide range of specialized G-Etronax types by downloading information about each material via our Material Finder and ask for getting samples from us. With the right choice of material, you can obtain the best base for meeting the tolerances, thus ensuring that the vanes permanently shut off the air to maintain the pressure in the vacuum pump.

Always expect the best

Meeting the requirement for narrow tolerances requires accurate machining and deep knowledge of the materials used in production.

We have been developing, producing and machining our composite materials since 1921, so no one knows or machines them as well as we do. This ensures you have the best possible conditions for a perfect result.

Benefits to you

  • Resistant materials
  • Fully automated machining facility
  • Focus on tolerances


Mechanical properties

Suitable for applications where the materials are exposed to mechanical impact.

Low thermal expansion coefficient

The material retains its shape when exposed to temperature fluctuations.

Chemical resistance

Withstands the effects from a wide range of chemicals which can damage many other materials.


Resistant material with long service life.

Thermal stability

The material remains functional and retains its properties even at high temperatures.