Cookies on the SKF website

We use cookies to ensure that we give you the best experience on our websites and web applications. By continuing without changing your browser settings, we assume you give your consent to receive cookies. However, you can change your browser cookie setting at any time.

Materials

The O-rings listed in this section are made of nitrile rubber (NBR) with 70 shA hardness as standard. This is the most common O-ring material and hardness used in hydraulic cylinder applications. On request, SKF can supply alternative hardnesses such as 80 shA or 90 shA. However, SKF generally recommends choosing O-rings with 70 shA and combining them with one or two back-up rings (→ Extrusion gaps and back-up rings). At operating temperatures above 100 °C (210 °F), fluorocarbon rubber (FKM) or hydrogenated nitrile rubber (HNBR) can be an appropriate materials, depending on the fluid.
SKF back-up rings listed in this section are made of polyurethane (TPU). On request, SKF can supply alternative materials and various hardness grades. Common back-up ring materials are listed in the designation system (table 1).
For additional information about O-ring and back-up ring materials, refer to Materials.
SKF logo