Perfluoroalkoxy (PFA) is a common material in which encapsulated O-rings are made. A type of fluoropolymer, it offers excellent flexibility and durability.
Encapsulated O-rings, of course, are circular mechanical seals with a flexible internal energizer or core and a more rigid outer jacket. They are used in a variety of sealing applications, such as automotive cooling systems, aerospace engines, semiconductor manufacturing, food processing, walk-in coolers, medical equipment and more. While they are all designed to prevent leaks, O-rings made of PFA offer several key benefits.
Heat Resistance
You can rest assured knowing that PFA encapsulated O-rings can withstand heat. With a PFA jacket, they can handle temperatures of up to 500 degrees Fahrenheit. That’s a higher maximum operating temperature than Fluorinated Ethylene Propylene (FEP) encapsulated O-rings. The PFA jacket protects the O-ring’s core from heat, ensuring a reliable seal in the hottest conditions.
Cold Resistant
In addition to heat, PFA encapsulated O-rings offer excellent cold resistance. They can handle temperatures as low as minus 450 degrees Fahrenheit. They won’t crack or otherwise degrade. Rather, PFA encapsulated O-rings will maintain their sealing capabilities as long as they stay within the minus 450 degrees to 500 degrees Fahrenheit range.
Chemical Resistant
PFA encapsulated O-rings are also chemical resistant. They hold up well when exposed to a wide range of chemicals, including acids, solvents and caustic substances. Whether acidic or highly basic, encapsulated O-rings can handle many different chemicals. This is in stark contrast to traditional rubber seals, which often permanently swell or break down when exposed to chemicals such as these.
Strong
Another benefit of PFA encapsulated O-rings is their strength. They are mechanically strong. They perform well in high-pressure sealing applications — all without suffering from permanent deformation or damage. This makes PFA encapsulated O-rings a popular choice for pressurized systems or dynamic sealing applications where the seals are constantly compressed and then released.
Available in Different Core Materials
You can find PFA encapsulated O-rings with different core materials. As previously mentioned, all encapsulated O-rings feature a core and jacket. PFA encapsulated O-rings specifically have a PFA core, but you can find them in different types of core materials. Common core materials include silicone and fluoroelastomer (FKM). The former is softer and more flexible, whereas the latter is former and more resistant to compression.
In Conclusion
With their exceptional resistance to heat, cold and chemicals, PFA encapsulated O-rings outperform many traditional alternatives. Their mechanical strength and ability to maintain integrity under pressure make them ideal for both static and dynamic applications.