Encapsulated O-Rings consist of a seamless and uniform PTFE encapsulation which entirely encloses a VMQ-made or FPM-made core. They combine the resilience and sealing force of an elastomer with the chemical resistance of PTFE. This produces an elastomeric PTFE ring with high sealing capability.
Unlike traditional O-rings, encapsulated O-Rings are resistant to solvents and are chemically inert (except for attack by alkaline metals, fluorine and some halogenated compounds at high temperatures). In addition, they have a great resiliency substantially equal to those of elastomers and FEP has a very low friction coefficient. Last but not least, their gas permeability is very low.
This is why we highly recommend their use in chemically hostile environments.