Piston rings

Piston rings – important components in cylinders

A piston ring, also known as a guide ring, piston guide or plunger ring, is fitted in cylinders, an important part of engines, pumps, pressure chambers and more. Inside the cylinder, a piston constantly moves up and down, which makes the cylinder a basis for mechanical movements in the application in question.

The piston movement inside the cylinder must be very accurate, and the piston must not touch the cylinder. It is the piston ring that guides the piston and its rods inside the cylinder, preventing contact between the piston and cylinder, reducing friction and absorbing strong transverse forces.

This puts a number of very special requirements on the piston rings, which, amongst other things, must be particularly hard-wearing and able to withstand aggressive and dusty environments and lubricants, which are often essential parts of cylinders.

Discover the advantages of piston rings made of composite materials

Cylinders are characterised as pneumatic and hydraulic cylinders, driven by gas/air and liquid, respectively, which is why it is important that the piston ring materials always function optimally in these environments. We always produce our piston rings from our cotton-based composite material Etronax, which is not only a very light and strong type of material, but also tolerates lubrication with water, oil and grease.

Depending on the specific need in each case, we produce piston rings from Etronax MF, Etronax MF G, Etronax MMF or Etronax DN. All these qualities reduce friction, but Etronax MF G contains graphite, which is self-lubricating and thus reduces friction even more when Etronax MF G is used. Both qualities are really strong and meet all the requirements needed to achieve the desired properties of the piston rings.

Should you wish to know more about our composite materials, you are more than welcome to get in touch with our specialised team or look up information about the specific properties of the materials via our Material Finder.

Burr-free piston rings with fine tolerances

Not just strength and resistance are important parameters for the production of piston ring. The machining of the final components is just as crucial for the final result. The tolerances of cylinder components are crucial for the final function and effect, which is why every single part must be produced with extremely low tolerances.

We machine the piston rings to precision with high-tech machining facilities handled by our specialised, quality-conscious employees. When ordering your piston rings from us, you are therefore guaranteed a perfect result with a burr-free surface and very fine tolerances.

Elektro-Isola – we make it easy for you

We are specialists in composite materials, so you are in safe hands when working with us.

Because we handle the complete process for the production of your components, from the production of the composite material itself through to machining and packaging, we can always provide you with a customer-specific process. Regardless of whether it is the machining, the supply or something else you have specific requirements for, we will tailor the solution to your wishes.

You are always welcome to get in touch with us to hear more about the many possibilities so we can design the solution together that gives you the best possible value. You may even be faced with a specific challenge to which you are looking for a solution. Whatever the case, we are always here to help you find the best solution.

Benefits to you

  • ISO 9001- and 14001-certified
  • Customer-specific tailoring of the material
  • Cutting-edge CNC machining

Properties of piston rings


Suitable for components where frictional and rolling resistance may occur.

Mechanical properties

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


The self-lubricating effect reduces friction and ensures the material has good sliding properties.

Can be lubricated with grease

The material can be lubricated with grease for optimal effect.

Can be lubricated with oil

The material tolerates many different oils and can thus be used in many environments.


Resistant material with long service life.

Easy to machine

The easy-to-machine material makes for unlimited possibilities.

Industries using piston rings

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