Shaft Seals

Shaft Seals for Rotating Applications

Shaft seals (WDR) are central sealing elements in machines that prevent lubricants from escaping or contaminants from entering the system. They are used, for example, in housings, shafts, and push rods. The common designs are regulated in Germany by the DIN 3760 standard.

Radial shaft seals (RWDR) feature a sealing lip that runs on the rotating shaft. This is usually pressed radially against the shaft by an integrated garter spring. For optimal sealing performance and low wear, the shaft surface must be ground free of helix. Modern designs sometimes do not use a spring or utilize PTFE sealing lips.

RWDR are also used as fork seals in motorcycle forks. There they seal axially moving, usually chrome-plated stanchion tubes and ensure the function of the integrated damping system. The installation direction always depends on the pressure differential – the open side points towards the higher pressure area.

The result: reliable sealing solutions for rotating and oscillating applications – even under demanding conditions.

• Standard-compliant design according to DIN 3760
• With or without garter spring, also as PTFE membrane shaft seals
• Used, for example, in engines, gearboxes, pumps, fork systems
• Axial and radial sealing possible
• Also known as "Simmerring®" – a protected trademark of Freudenberg

PTFE shaft seals exhibit higher temperature resistance and significantly better chemical resistance compared to conventional elastomer shaft seals. The excellent dry-running properties of PTFE are also beneficial.