HNBR is widely used in the automotive and petrochemical industries because of its durability under high temperature, fuel,oil, and chemical exposure.
This makes HNBR an optinal material for the replacement of specialized rubbers like FKM (VITON)(fluorocarbon rubber), CR (chloroprene), and other materials.
Here we compare HNBR and FKM to highlight key differences and applications of each material.Hopefullt it could help you for the choice between HNBR and FKM material.
HNBR Products and Applications
HNBR products include O-rings, gaskets, seals, Y-rings, V-rings, and U-rings. These products are especially for applications in oil-resistant and high-temperature automotive parts, such fuel system, HVAC system,engine and transmission.
In the oil and gas industries, HNBR is particularly well-suited for high-temperature, high-pressure environments, as its resistance to harsh media like H₂S, CO₂, methane, diesel, steam, and acids is superior to many materials, including FKM.
Furthermore, HNBR offers excellent radiation resistance, making it suitable for nuclear power plant seals.
Property Comparison of HNBR and FKM
| Properties | HNBR | FKM |
| High Temperature Resistance | Up to 150°C (extended to 170°C in specific applications) | Higher than HNBR; up to 200°C-250°C, ideal for continuous high-temperature operations |
| Low Temperature Resistance | HNBR can work as static sealing under -30℃, special HNBR can go down to -40℃. Performance under high termperature need to be balanced. | Normal FKM can work under-20℃,special FKM such as Viton GLT could work lower at low -35℃ with much higher cost than HNBR. |
| Oil and Chemical Resistance | Highly resistant to oils, diesel, H₂S, CO₂, methane, acids, and steam; | Exceptional resistance to oils, fuels, acids, and aggressive chemicals; performs well with hydrocarbons |
| Mechanical Strength | High tensile strength (20–40 MPa) | Lower tensile strength than HNBR |
| Wear Resistance | Excellent, particularly at 150°C; maintains stability in oil immersion | Weaker than HNBR in dynamic conditions |
| Ozone and Weather Resistance | Superior, with no cracking or ozone deterioration over prolonged exposure | Excellent, slightly better than HNBR, particularly suited for prolonged outdoor exposure |
| Radiation Resistance | Higher than silicone, FKM, and PTFE; well-suited for nuclear environments | Moderate, but satisfactory for most industrial applications outside nuclear and aerospace |
Key Application Comparison
Automotive: Both HNBR and FKM excel in automotive seals and gaskets, where HNBR is frequently preferred for fuel systems, oil gaskets, and O-rings, thanks to its cost efficiency and high mechanical strength. FKM, with its broader temperature range, is often chosen for turbocharger seals, fuel injector seals, and components exposed to continuous high temperatures.
Oil and Gas : HNBR stands out in oil and gas applications due to its resistance to harsh drilling media. It retains properties under exposure to H₂S, CO₂, and high temperatures, where FKM may degrade. FKM is favored when only chemical and oil resistance is required without significant pressure and abrasion.
HNBR and FKM are both offer unique strengths.
HNBR provides a balanced solution for applications where high resistance to temperature, chemicals, and mechanical stress is needed at a competitive cost.
FKM remains the material of choice for extreme high-temperature environments and complex chemical exposures.
For more details,please contact OBT Rubber Seal for customized HNBR and FKM rubber seal(such as O-Ring, Gasket) solutions according to your application.
