Encapsulated o-rings have an elastomer on the inside, coated with an inert polymer to produce an end product that combines the best qualities of both.
The outer coating is usually Fluorinated ethylene propylene (FEP) or Perfluoroalkoxy alkane (PFA). These polymers are similar to Teflon, with a high level of chemical and heat resistance. The inner elastomer provides flexibility, resiliency and compressive strength. For many applications, an encapsulated o-ring can perform as well as a solid Teflon o-ring at a lower cost.
Encapsulated O-rings may not seal as well in low temperatures. The other drawback may be that most encapsulated O-rings are extruded and spliced, so the bond site may be weaker and less resistant.
Not sure which type of o-ring you need for your application? Our experienced staff can help you find the ideal balance of price and performance. Contact us at 800.874.0877.