4 Facts You Need to Know About Oil Seals

A common cause of leaks in engines is debris getting caught in the fork seals, keeping them open and letting the oil slip through. So, how do you fix this problem? That's where the little round device comes in handy - the oil seal.

Oil seals are devices used to prevent dirt, dust, water or any other foreign material from contaminating the shafts and bearings in rotating shaft equipment. In this article, we'll cover the basics of what you need to know when using oil seals.

Valve Oil Seal FKM NBR

Dust and debris are the cause of failure

The ingress of dust and debris is one of the most common causes of oil seal failure. For example, in high-pressure applications, even the smallest deposits can create gaps in the seal, leading to oil leakage and dirt entry.
An effective way to ensure that particles do not contaminate oil seals is to store them in containers or sealed bags away from areas where dirt and debris are prevalent. Resealable heavy-duty plastic bags and bins are ideal for protecting shaft seals.

Oil Seal Dust Wiper for Construction Machines

Basic Component Composition

Sealing Element - The sealing element forms the inside of the oil seal. Its purpose is to stop fluid from escaping between the shaft and the housing. Materials typically used are fluorinated rubber, silicone, nitrile and acrylic.
Metal Housing - The metal housing is used as the frame of the oil seal. Its primary function is to give the seal rigidity and strength. The choice of material depends on the environment in which the seal will be used.
Spring - The retaining spring is a steel ring located at the end of the main seal lip. It is used to apply pressure to the seal lip on the shaft. Typically, it is made of carbon steel or stainless steel.

Proper installation is key

Improper installation can cause the oil seal to fail. It may tilt or misalign in the bore while being hammered into place. Having said that, proper setup will help ensure an effective sealing process.
One way to identify an improperly installed seal is to check for uneven shearing of the rubber after use. If this is evident, make adjustments by properly aligning the installation tool before pressing the seal into place.

Combi Oil Seal

Rubber Housed and Metal Housed

Metal housing oil seals are usually installed in a housing bore made of the same material. This allows for uniform expansion and contraction of the material during operation and prevents leakage. This type performs best when used in steel housings.
Meanwhile, rubber housing oil seals are used in conditions where metal housing seals may fail (e.g., due to thermal expansion). Unlike metal housing types, these seals do not rust. In addition, they can seal slightly damaged housings better than metal-covered seals because rubber provides a more consistent seal at high temperatures.

NEW Rubber Combined Gaskets Bonded Seal

Where to buy oil seals

Oil seals play an important role in preventing lubricant leakage by closing the space between rotating shaft equipment components. They also prevent dirt, dust and other contaminants from clogging equipment. Installing them correctly allows engines, pumps and pipes to operate more efficiently.

HONGLEI is a leading supplier and seller of oil seals, selling high-quality industrial and engineered parts made from a variety of materials. Browse our online store to see our full range of products, and contact us to get the quote.