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Oil seals from billi seals

A oil seal, also known as a radial oil seal, is one of the rotary seals. The sealing rings are used to seal the space between the (rotating) oil and housing. As a leak-free, active sealing element, a rotary oil seal (abbreviated WDR) consists of an outer casing, a stiffening ring, a spring-supported sealing lip and optionally a dust lip. The materials used for the sealing lip and casing depend on the requirements and the area of application of the oil seal. This is why billi seals' product range includes all standardised designs, including variations. We also produce customised products according to your requirements.


Oil seals from billi seals - your advantages at a glance

  • Production from 1 piece
  • Production of individual items
  • Customised production
  • Individual customisation according to customer requirements
  • Advice from experts
  • High-quality gaskets
  • Fast order processing
  • Large warehouse
  • Short delivery times

Oil seals according to DIN 3760

WDR according to DIN 3760 are standardised designs. The standardised designs include the code letters "A" (rubberised WDR), "B" (open metal housing) and "C" (closed metal housing) as well as the codes "AS", "BS" and "CS", whereby the "S" stands for dust lip.


FAQs - Questions and answers about our oil seals

What materials are oil seals made of?

The sealing lip and outer casing of most oil seals are made of different materials. Depending on the model, the lips are made of NBR (nitrile butadiene rubber), FPM/FKM (fluororubber), EPDM (ethylene propylene diene monomer rubber) or MVQ (silicone rubber). Metals or elastomers are used for the outer casing. There are also PTFE (polytetrafluoroethylene) and fabric-reinforced oil seals. In the latter case, for example, NBR or FPM is combined with fabric. Special materials include H-NBR, ACM or FVMQ.

What is the difference between radial oil seals and axial oil seals?

Radial rotary oil seal (RWDR) is the exact term for oil seals. Axial oil seals are generally used for subordinate sealing tasks. For example, splash water and dust protection are areas of application for axial oil seals. In RWDR, they are often used as secondary seals for particularly high dirt loads. Common designs of axial oil seals are the gamma ring and the V-ring.

Where are oil seals used?

The areas of application for oil seals are extremely diverse due to the numerous designs. The sealing rings are used in construction machinery, agricultural machinery and mechanical engineering in general. They are also used for sealing in hydraulic pumps, household appliances, hydraulic motors, power tools and wind energy and air conditioning systems. Beyond their original purpose, they are used as fork seals in motorbikes.


Catalog O-Ring Seals

Catalog O-Ring Seals

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Mechanical Seals here

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