Leather is probably the oldest of the lip materials still in common use, but the move towards mass production methods has seen a massive increase in the development of synthetic rubbers which lend themselves to accurate and repeatable injection and compression moulding. Nitrile (NBR) is still by far the most common elastomer for “normal” use, whilst Viton® (FKM/FPM) is rapidly replacing Polyacrylate (ACM) and Silicone (VMQ) for high-temperature applications. Viton® also has high resistance to abrasion and chemical attack making it a preferred elastomer. Recent developments in the use of PTFE for Rotary shaft seals has caused widespread interest particularly for high-speed shaft rotation or poor lubrication applications.
Dynamic seals called bearing isolators are used to shield bearings from external impurities. They are revolving (rotor) and stationary (stator) elements. O-rings or strong seals are used in some bearing isolators, while they are constructed like labyrinths in others.
Oil seals, also known as rotary shaft seals, are a type of gasket used to prevent lubricant leakage and contamination in rotating machinery by creating a barrier between the moving and stationary parts.
Additionally, lubricants can be used on both sides of the oil seal to reduce friction and enhance sealing performance. The sealing process is crucial for preventing contaminants from entering machinery or equipment while keeping essential fluids contained within.


If you are looking for the highest temperature resistant oil seals, Perfluoelastomer can go up to 600°F. If you are more concerned for low temperature, Chloroprene can go all the way down to 40°F, which is why it is used most commonly for refrigeration. And if FDA applications or medical devices are your primary concern, Butyl , the all petroleum compound, will be your best choice. As you can see, when choosing the right material to work with, you must analyze several other key components to help choose the right one.
Seals are essential to protecting the bearings of any rotating shaft assembly -They prevent contaminants such as dirt, dust and water, while also preserving the system’s lubricant.
* KOYO is a registered trademark of JTEKT.
It is essential to regularly check and replace spark plugs as needed to ensure the engine runs smoothly and efficiently. Over time, spark plugs can wear out due to the intense heat and pressure inside the engine cylinders. Worn-out spark plugs can lead to misfires, poor fuel economy, and even engine damage if left unattended.
The cover is fixed by nuts or bolts on top, or by screws round the edge. Loosen them all and remove them with their washers. If there are several oil-sealing washers under each fixing, note their order.
