Fluoropolymer jacket. Elastomeric core. Chemical resistance where standard elastomers reach their limit. Circular and custom profiles.
PFA and FEP encapsulated seals combine the broad chemical resistance of a fluoropolymer jacket with the compression and recovery performance of an elastomeric core. Supplied in catalog sizes and nonstandard configurations on application. When the process media rules out standard elastomers and FFKM is cost-prohibitive, encapsulated seals are the engineered middle ground.
PFA or FEP — the distinction matters for your application.
Both PFA and FEP jackets deliver broad chemical resistance and a non-stick, low-contamination sealing surface. The selection between them is application-dependent — not always interchangeable.
PFA — Perfluoroalkoxy
Higher continuous service temperature than FEP. Better retention of mechanical properties at elevated temperatures. Preferred for high-temperature process environments, steam service, and applications requiring thermal cycling resistance. PFA jacket encapsulated seals are the standard choice for pharmaceutical manufacturing, aggressive CPI environments, and high-purity fluid paths where thermal demands are significant.
FEP — Fluorinated Ethylene Propylene
Excellent chemical resistance across a broad media range. Lower service temperature ceiling than PFA but superior optical clarity — relevant where visual inspection of the seal or fluid path is required.
If the application sits at the boundary between the two, PRP’s application engineering support covers jacket material selection alongside core compound and geometry — before you commit to a configuration.
Catalog sizes stocked. Non-standard on application.
PFA and FEP encapsulated seals supplied to standard AS568 and metric dash numbers across the catalog range. Non-standard cross-sections and IDs available upon application — lead time dependent on jacket material, core compound, and configuration.
We provide the smallest IDs and tightest tolerances in the business. Encapsulated seals are sourced by PRP from the best-in-class specialty engineering company and undergo our rigorous in-house quality controls and secondary processes.
Where standard elastomers fail and FFKM is over-specification.
PFA and FEP encapsulated seals are the engineered solution for aggressive media environments where standard FKM or EPDM elastomers are chemically incompatible and full FFKM is cost-prohibitive or geometrically constrained. Typical application environments include pharmaceutical and biopharma process equipment, aggressive CPI fluid paths, semiconductor wet process tool components, and high-purity fluid transfer systems.
VeriClean Seals™ — High Purity Fluid Paths
Encapsulated seals are frequently specified for the same high-purity fluid paths where seal surface cleanliness is a documented requirement. VeriClean Seals™ processing — ISO Class 7 cleanroom processing with particulate measurement from ≥1.3 µm — is available for encapsulated seal configurations. No change to jacket material, core compound, or dimensions. While FEP and PFA typically carry lower surface particulate burdens than homogenous elastomer seals, the VeriClean Seals program
still documents significant particle control.
