Things to Consider When Choosing an Oil Seal - Monroe Engineering

Oil seals play an important role in engines, hydraulic systems, pumps, gearboxes and machinery. They are designed to prevent lubricants or other oils from leaking out of parts while also preventing dirt and debris from entering parts.

For more information, please visit NNK.

Shafts, for instance, often feature an oil seal. Without this otherwise simple mechanical seal, oil will likely leak out, leaving the shaft susceptible to friction-related wear and tear. Whether you’re planning to use it on a shaft or any other part, however, there are several things you should consider when choosing an oil seal.

Diameter

Oil seals are available in different sizes. By considering the diameter, you can choose an oil seal that fits perfectly around the part with which you intend to use it.

Keep in mind that most oil seals have an inner diameter and outer diameter. The inner diameter represents the width from the inner edge of an oil seal to the inner edge on the opposite side. The outer diameter represents the width from the outer edge of an oil to the outer edge on the opposite side. Therefore, the outer diameter will always be wider than the inner diameter.

Material

You should consider the material when choosing an oil seal. Oil seals must be able to withstand regular exposure to fluids, which may be accompanied with heat and pressure. If a seal is made of weak or low-quality materials, it may fail to create a tight seal. Fortunately, you can find oil seals in many effective and high-quality materials, such as FKM, silicone, polyacrylate and Nitrile Buna-N 70 durometer compound.

FKM is a type of fluorocarbon-based fluoroelastomer that boasts one of the widest temperature ranges and chemical resistance. Silicone is an elastic synthetic material consisting of silicon, oxygen, carbon and hydrogen. Polyacrylate is a type of highly durable polymer consisting of acrylic acid. Finally, Nitrile Buna-N 70 durometer compound is a versatile and effective seal material that’s compatible with many other materials.

Contact us to discuss your requirements of Oil Seal Material. Our experienced sales team can help you identify the options that best suit your needs.

Temperature Range

Don’t forget the temperature range when choosing an oil seal. Different types of seals have different temperature ranges. Some of them can handle higher temperatures than others, making them ideal for applications involving a lot of heat.

As previously mentioned, FKM seals have one of the widest temperature ranges. They can typically handle temperatures as low as minus 40 degrees Fahrenheit and as high as 400 degrees Fahrenheit. Silicone seals also have a wide temperature range of minus 90 degrees Fahrenheit to 340 degrees Fahrenheit. Polyacrylate seals have a slightly narrower temperature range of minus 30 degrees Fahrenheit to 300 degrees Fahrenheit, followed by Nitrile Buna-N 70 durometer compound at minus 65 Fahrenheit to 250 degrees Fahrenheit.

 Materials & Temperature

 Applications

 Use With These Fluids

Are you interested in learning more about rubber oil seal? Contact us today to secure an expert consultation!

Simriz®
-10 C to +305 C Compound Specific
Simriz® oil seals are molded of an elastomer that has the broadest chemical resistance of any elastomeric material. They combine all the resilience and sealing force of an elastomer with a chemical resistance approaching that of FEP. most chemicals Aflas®
-10 C to +204 C Compound Specific
Aflas® oil seals are made from a unique fluoroelastomer that is resistant to petroleum oils, steam, hydrogen sulfide and amine corrosion inhibitors. petroleum oils, H2S, steam Carboxilated Nitrile
-54°C to 135°C Nitrile oil seals are made from a compound that tolerates low temperatures and has excellent abrasion resistance. petroleum oils, water FKM Fluorocarbon
-40 C to +204 C Compound Specific FKM Fluorocarbon oil seals feature excellent resistance to petroleum products and solvents. They have good high temperature and low compression set characteristics. They are suited for use with wide chemical exposure situations and for hard vacuum service. petroleum oils, gasoline, transmission fluid Fluorosilicone
-56°C to 204°C A fluorosilicone oil seal combines the good high and low temperature stability of silicone with the fuel, oil, and solvent resistance of fluorocarbon. This oil seal is resistant to petroleum oils and gasoline. petroleum oils, gasoline Highly Saturated Nitrile (HSN, HNBR)
-26°C to 160°C Oil seals made from highly saturated nitrile have excellent resistance to petroleum oils and sour gas. Because of the extended temperature range of highly saturated nitrile, it is becoming a preferred compound in the oil patch. petroleum oils, H2S, CO2 Nitrile (Buna-N)
-40°C to 135°C
Nitrile (Low-Temp)
-65°C to 120°C Nitrile is presently the seal industry's most widely used elastomer. Nitrile oil seals combine excellent resistance to petroleum based oils and fuels, silicone greases, hydraulic fluids, water and alcohols. Nitrile has a good balance of working properties such as low compression set, high tensile strength, high abrasion resistance, combined with a low cost. petroleum oils,
water, hydraulic oils Polyurethane
-40°C to 105°C Polyurethane is an excellent material with high abrasion resistance characteristics and high tensile strength. Polyurethane oil seals are used in high pressure hydraulic systems where highly stressed parts are subject to wear. These seals are resistant to petroleum oils and hydraulic oils. petroleum oils,
hydraulic oils FEP
-20°C to 204°C FEP is a tough, chemically inert polymer possessing an incredible working range. Oil seals from this material are for static and slow intermittent dynamic situations. FEP is hampered by a poor memory at low temperature. most chemicals Polyacrylate
-20°C to 170°C Polyacrylate has better heat resistance than Nitrile. It works well in high surface speed oil seals. petroleum oils, Freon