Sealing Technology Reference

Valve Sealing & Emission Control Systems

Which sealing DESIGN to choose, not just which material — 10 stem, seat and body-joint sealing technologies, how each works, when to use it, and the standards (ISO 15848, API 622, API 624, API 607) it satisfies.

Stem Sealing

Live-Loaded PackingA spring (Belleville washer stack) maintains continuous compressive load on the stem packi...Bellows Seal StemA welded metal bellows fully encloses the stem between the disc and the packing, providing...Flexible Graphite Packing SystemDie-formed flexible graphite rings replace older fibre/PTFE packing sets, giving stable se...Secondary (Double) Stem SealA second, independent sealing element above the primary packing - often a lip seal or O-ri...

Seat Sealing

Spring-Energized PTFE Seat SealA PTFE seat jacket with an internal spring (canted-coil or C-ring) provides continuous, se...Fire-Safe Soft Seat (Primary/Secondary)A primary soft (PTFE or similar) seat gives normal bubble-tight shutoff; a secondary metal...Metal-to-Metal SeatThe disc or ball seals directly against a hardened metal seating surface with no elastomer...Elastomer O-Ring SealA moulded elastomer O-ring (EPDM, NBR, FKM/Viton, FFKM) provides low-torque, low-cost seal...

Body / Joint Sealing

Spiral-Wound Gasket Body JointA metal winding (usually stainless) interleaved with a soft filler (graphite or PTFE) form...Ring-Type Joint (RTJ) SealA solid metal ring (octagonal or oval) seats into matching grooves machined into the flang...

Sealing technology is standard engineering practice, indicative for reference — the exact design is confirmed against the datasheet and governing standard. Machine-readable version in the Data Commons. See the material side of trim selection in the Trim Selection Guide.