7 Important Factors to Consider When Choosing Oil Seals

An oil seal is a type of seal used in various industrial equipment to close the gap between its moving and non-moving parts. These oil seals help prevent the leakage of lubricant under high pressure and stop foreign objects from entering the machine. Playing such an important role, these oil seals must be carefully selected. This article discusses the types of oil seals and guides you through the important factors in selecting the right oil seal for your industry.

Types of oil seals – based on material

There are a variety of seals available depending on the type of material. Some of the types of oil seals are as follows.

Rubber oil seals.

Rubber seals are the most common type of sealing solution and are suitable for tight sealing. Rubber seals are corrosion resistant and can be used in both high and low-pressure applications. Buna N, polyacrylate, Viton®, silicone, and PTFE are a few common types of rubber materials used for this purpose. Each material has typical properties, so you must choose your rubber material carefully for your application.

Metal Housing Oil Seals.

These seals have a stamped metal housing and an elastomer bonded sealing lip. Carbon steel is the metal used to make the case. The housing protects the lip seal during installation. Metal housing seals are typically used in high-pressure or high-temperature applications.

Internal Expanding Sealing Components (Type NM)

Sealing Components

These seals have good operating properties and are typically preferred for abrasive applications. Seals are typically used on shafts with higher surface roughness than rubber seals.

7 Important Factors to Consider When Choosing Oil Seals

With the wide variety of seals available, choosing the right seal for your application can be a daunting task. The following factors will help in making the right choice.

Lubricant: If you choose lubricated seals, make sure they are continuously lubricated with an oil that has the viscosity required for the application and that the lubricant is compatible with the elastomeric material of the seal.

Shaft Finishing: A good shaft surface finish provides a very effective oil seal. Ground or polished shafts with concentric finish marks provide the best seal and prevent leakage even during shaft rotation. Therefore, it is important to ensure that shaft finishes are well maintained.

Shaft and bore tolerances: The seal must be strong enough to withstand the stresses and vibrations caused by the shaft and bore. The authenticity of metal and elastomeric materials makes shaft and bore tolerances possible. Therefore, check that the material meets these requirements before purchasing a seal.

Large Gap Ultra-high-pressure Sealing Components

Large Gap Ultra-high-pressure Sealing Components

Shaft hardness: The life expectancy of a seal is measured by the hardness of its shaft. Shafts must have a Rockwell hardness of 30 or higher. This RC hardness protects seals from damage when they are exposed to abrasive contaminants or high pressures. Therefore, it is an essential factor.

Temperature: The process temperature should not exceed the temperature of the seal elastomer. Any increase or decrease in temperature may affect the sealing ability of the seal. Therefore, this is an important point to consider.

Pressure: Most seals are designed for applications that may withstand pressures as low as 8 psi. However, if they are subjected to even very low pressures, it is important to ensure pressure relief.

Shaft Speed: Shaft speed depends on many factors including shaft finish, concentricity, type of fluid being transported, and type of oil seal material. Therefore, each of these factors must be considered to achieve maximum shaft speed.

In addition to these factors, it is important to source quality seals from a trusted seal manufacturer.

JIANKE is a manufacturer of high-performance sealing for hydraulic tester and pipeline solutions with an emphasis on safety, longevity, and productivity.

JIANKE provides quality oil seals for automotive, oil and energy, and other industrial applications. For more information about the sealing components, welcome to contact us today or request a quote.