- The choice of material for a lip seal gasket depends on the specific application requirements. Common materials include nitrile rubber, silicone, fluoropolymer (PTFE), ethylene propylene diene monomer (EPDM), and neoprene. Each material has its own unique properties, such as temperature resistance, chemical resistance, and flexibility. For example, PTFE is known for its high temperature resistance and chemical inertness, making it ideal for use in harsh environments. Nitrile rubber, on the other hand, is a popular choice for its good oil and fuel resistance.
- Improper use of sealants.
Operating conditions such as the engine’s temperature, position, size, pressure and shaft speed largely determine which individual oil seal composition is most suitable for every individual application.
Replacing gaskets and oil seals
- Oil seals are integral components in the operation of machinery, providing a vital barrier between the internal lubricated parts and the external environment. These seals prevent the leakage of oil, which is essential for the proper functioning of the machine's moving parts. With their robust design and durable construction, oil seals ensure long-lasting performance and reduce maintenance costs.
- a. Nitrile Rubber (NBR) – this is the most commonly used material. It has good heat resistance properties and has good resistance to salt solutions, oils, hydraulic oils, and gasoline. Operating temperatures are recommended from -40 to 248⁰ F (-40 to 120 deg.C). Nitrile also functions well in a dry environment, but only for intermittent periods. The disadvantage of this material is poor chemical resistance.
Cassette seals are designed to maximise grease or oil retention and protection against liquid or solid contaminants. These seals are provided with their own bushings in which dirt is kept out and oil/grease kept in by a multi-lip seal.
- - Replace the gasket according to the manufacturer's recommendations or when it shows signs of wear or damage.
White rubber gasket sheets are widely utilized for their adaptability and sealing properties. These sheets are commonly used in applications where a durable and flexible sealing solution is required. The white rubber material offers resistance to heat, chemicals, and weathering, making it suitable for diverse industrial and commercial applications. The sheets can be custom-cut to fit specific requirements, providing a versatile and effective sealing solution.


PTFE is special in that a pre-tensioned spring is not required. This is because the material returns to its original shape when heated, also known as the shape-memory polymers (SMPs) effect. These oil seals are also supplied as integrated parts, where it only needs to be installed as one component.
Figure 14.4. Effect of aeration on oil aging.5 Chart shows percent retained elongation after aging for 28 days at 150°C in Mobil 276.