Our brands in Piston Seals
Piston (cup) seals
Piston seals, sometimes referred to as piston cup seals or piston rod seals, ensure that the pressure in pneumatic or hydraulic cylinders remains high. As a result, the piston moves back and forth. In addition, some piston seals keep gas or liquid from leaking within the application. This product is widely applicable. You will find it in small gearboxes, for example, but also in large ships or wind turbines.
If you want to order piston seals, you must consider the type, the dimensions and the material from which the product is made.
Types of piston seal
ERIKS offers different types of piston rod seal. The exact type you need depends on the conditions in your application. Such as the installation dimensions, the pressure and the speed of rotation.
Piston seal dimensions
The size of a piston seal depends on the dimensions of your application, for example, those of the hydraulic piston. Always consider the inner diameter of the groove (d), the outer diameter (D) and the groove length. Once you know these metric dimensions, you can easily select the right product.
Piston seal materials
We use different materials for the production of piston rod seals, such as NBR, FKM, polyurethane, PTFE and rubber fabric. Each material is the basis for a unique compound; i.e. a recipe of different material components that result in specific properties when combined.
It is important to ensure that the material used for a piston seal does not react inappropriately to the conditions of your application. So you must always consider the medium, the temperature, the pressure, the uptime and the guide arrangement. The summary below provides concise information about the most popular materials and their properties.
- NBR piston seals
Many piston seals are made of NBR, also known as nitrile rubber. This rubber material is ideal for use as a seal in applications involving hydraulic oils and lubricating oils. However, it is not very resistant to UV radiation, ageing and high temperatures (above +120°C).
- FKM piston seals
FKM is the sealing material to use for applications involving strong chemicals and high temperatures. This rubber material is also known by its brand name, Viton, and is suitable for applications up to +200°C. Furthermore, the standard compounds are resistant to many strong acids, but not to hot water or steam. Only a few special FKM compounds are suitable for extremely low temperatures (down to -40°C or below).
- Polyurethane piston seals
Compared to other elastomers, polyurethane has good wear resistance, a high tear strength and extensive elasticity. The material's gas permeability is low, making this type of seal particularly suitable for hydraulic cylinders. Furthermore, this material (PUR with a special ester polyol) is resistant to hydrolysis and water.
- PTFE piston seals
PTFE, also known by the brand name Teflon, is highly resistant to strong acids and bases. This plastic is not wear-resistant, and unlike the elastomers mentioned above, also not elastic.
- Rubber fabric piston seals
Rubber fabric piston seals generally have the same properties as the rubber they incorporate. There is one important difference however: because cotton or another fabric is woven through the rubber, the material is even stiffer. This makes it more resistant to compression. You use this type of piston seal, for example, in large cylinders in heavy duty applications.
Would you like more information about the chemical resistance of our materials? Refer to our Chemical Resistance Guide for a handy overview.
Ordering piston (cup) seals at ERIKS
Are fitting instructions provided when I purchase a piston seal from ERIKS?
When you want to fit your piston seal, you can obtain personalised instructions from us via the enquiry form. This ensures that your application will work properly.
Can I purchase tools for fitting piston seals from ERIKS?
You need specific tools to install piston seals. You can order them from us quickly and easily via the enquiry form. This ensures that you have the right equipment to hand.
What prices does ERIKS charge for piston seals?
The price of our piston seals is shown on the product pages. If the price is not immediately visible, it will be displayed after you have logged in.
What delivery times does ERIKS offer for piston seals?
The delivery time for a specific piston seal is indicated on the page for that product. If you require a product more quickly, we advise you to choose a suitable alternative. You have two options:
- Choose a different material that also works in your application.
- Use our quick-supply solutions, such as the SealXpress service.
If you need help finding a good alternative, please contact us via the enquiry form.
Can I order custom piston seals?
Are you looking for a piston seal of a different size, shape, colour or material? Let us help - contact us via the enquiry form.
