Not all rubbers are built for heat, fuel, or chemicals. If your seal fails near an engine or pump line, chances are you’re not using fluoroelastomer.
Fluoroelastomer rubber is a high-performance synthetic rubber known for its excellent resistance to heat, oils, fuels, and aggressive chemicals. It’s commonly referred to by trade names like Viton®.
In my line of work, I often recommend fluoroelastomer when NBR or EPDM just can’t take the heat—or the solvent. It’s the go-to material for sealing in the toughest industrial environments.
What makes fluoroelastomer different from other rubbers?
Standard rubbers break down in oil or swell in fuel. Fluoroelastomer stays intact—keeping seals strong under fire, fluid, and friction.
Fluoroelastomers are chemically stable, thermally durable, and resistant to swelling or degradation from oils, fuels, and most acids.
🛠️ Key Properties of Fluoroelastomer
| Property | Performance Range |
|---|---|
| Temperature resistance1 | -20°C to +230°C (some grades to +300°C) |
| Chemical resistance2 | Excellent against hydrocarbons, acids, oils |
| Compression set | Low—good long-term sealing under pressure |
| UV/ozone resistance | Excellent |
| Flame resistance3 | Self-extinguishing |
We often use fluoroelastomer for shaft seals in hot oil pumps and fuel systems, where EPDM or NBR would break down or swell within weeks.
What is fluoroelastomer used for?
Any place where rubber meets oil, solvent, or heat—fluoroelastomer is usually the answer.
Fluoroelastomer rubber is used in O-rings, gaskets, shaft seals, fuel hoses, and diaphragm components in automotive, aerospace, chemical, and industrial machinery.
📍 Typical Applications
| Industry | Product Application |
|---|---|
| Automotive | Crankshaft seals, valve stem seals |
| Aerospace | Jet fuel system O-rings |
| Chemical plants | Pump seals, tank gaskets |
| Oil & gas | Valve seats, fluid connectors |
| HVAC | High-temp compressor seals |
One European customer requested a gasket that could handle aggressive cleaning fluids4 and elevated temps. We offered a custom FKM formulation5—and their equipment ran for two years without a single seal failure6.
What is the difference between fluoroelastomer and Viton?
“Viton” is the name most people know—but there’s more behind it.
Viton is a brand name of fluoroelastomer developed by DuPont (now Chemours), while fluoroelastomer is the general term for this class of rubber.
✅ Understanding the Naming
| Term | Meaning |
|---|---|
| Fluoroelastomer7 | Generic material category (FKM per ISO) |
| FKM8 | ISO designation for fluoroelastomer |
| Viton®9 | Trademarked brand of FKM by Chemours |
| Other brands | Dyneon™, Tecnoflon™, etc. |
So, all Viton is fluoroelastomer—but not all fluoroelastomer is Viton. At Julong, we offer both branded and non-branded FKM options depending on customer requirements.
What are the different grades of fluoroelastomer?
Not all FKM rubbers are the same. Some are built for fuel, others for acid. Some for flexibility, others for heat.
Fluoroelastomers come in multiple types—A, B, F, and perfluorinated grades—each optimized for different combinations of heat, chemical resistance, and flexibility.
🧪 FKM Grade Comparison
| Grade | Structure | Specialty |
|---|---|---|
| Type A10 | Vinylidene fluoride | Standard oil/fuel resistance |
| Type B | Hexafluoropropylene | Improved chemical resistance |
| Type F11 | TFE + propylene + VDF | High temp + base resistance |
| FEPM | Perfluorinated | Best for acids, amines, high heat |
If a customer requests FKM for brake fluid or steam, we steer them toward Type F or perfluorinated12 materials. Type A won’t survive in such environments.
When should you choose fluoroelastomer over other rubbers?
When failure is not an option—and conditions are extreme—FKM is the right call.
Choose fluoroelastomer when your system involves aggressive chemicals, high temperatures, fuels, or long-term static compression in industrial environments.
✅ When to Use Fluoroelastomer
| Condition | Use FKM? |
|---|---|
| Engine oil contact | ✅ Yes |
| Fuel, diesel, kerosene | ✅ Yes |
| Steam or water | ❌ No – use EPDM |
| Food or medical use | ❌ No – use Silicone |
| General hydraulic oil | ✅ Yes |
| Chemical spray environment | ✅ Yes |
We helped an HVAC contractor switch from NBR to FKM for a rooftop unit exposed to acid rain and high ozone levels. Their previous seals lasted 3 months—ours lasted over a year.
Conclusion
Fluoroelastomer is the elite choice in the rubber world—built for the toughest jobs where heat, oil, and chemicals destroy ordinary seals.
Need high-performance FKM seals for your system?
Contact Julong Rubber or Request a Quote for custom-molded FKM O-rings, gaskets, or lip seals.
Or chat with us directly on WhatsApp:
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Understanding the temperature resistance of fluoroelastomer is crucial for applications in extreme conditions. Explore this link for detailed insights. ↩
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Fluoroelastomer's chemical resistance is vital for industries dealing with harsh substances. Discover more about its advantages here. ↩
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Flame resistance is a key safety feature in many applications. Learn more about fluoroelastomer's self-extinguishing properties. ↩
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Discover the best gaskets for aggressive cleaning fluids to ensure your equipment operates efficiently and safely. ↩
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Explore this link to understand how custom FKM formulations can enhance performance in demanding environments, ensuring reliability and longevity. ↩
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Learn about the common causes of seal failure to prevent costly downtime and improve equipment reliability. ↩
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Explore this link to understand the properties and uses of fluoroelastomers in various industries, enhancing your knowledge on this versatile material. ↩
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Learn about FKM and its significance in the field of materials science, providing insights into its applications and benefits. ↩
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Discover the advantages of Viton® over other materials, which can help you make informed decisions for your projects. ↩
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Learn why Type A FKM is not recommended for brake fluid or steam, helping you choose the right material for your needs. ↩
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Explore the unique properties of Type F FKM, ideal for high temperature and base resistance applications, to make informed material choices. ↩
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Discover the advantages of perfluorinated materials for acids and high heat, ensuring optimal performance in demanding environments. ↩
