The use of the hard insert seat nowadays is largely used in the valves; in fact, thanks to the many types of thermoplastics, it is possible to obtain the best sealing results related to the choice of the most technopolymer suitable for the applications of the valves, assessing the pressure, the operating temperature and the fluid flow type as a whole.
The most performing types of thermoplastics are:
- Polytetrafluoroethylene (P.T.F.E. filled CG, sometimes filled glass – PTFE DYNEON TFM – PTFE CABFLUOR M25)
- Polyamide (DEVLON – NYLON 6MOS2 – NYLON PA12G / Lauramid – ERTALON 6XAU – SINVEX SMX – Etc.)
- Polyether ether ketone (virgin PEEK – PEEK filled PTFE – PEEK filled PTFE +CG – PEEK filled CARBON 30%)
- Polychlorotrifluoroethylene (PCTFE / Kel-F)
- Polyimide (VESPEL Dupont)
The sealing gasket must be machined with tolerances such as to ensure perfect correspondence during pressing inside the groove and total absence of air.
The thermoplastic rigid insert is then pressed into the groove of the seat and subsequently machined to give the correct sealing profile with the ball. The insert profile geometry can take different shapes according to the projects.
Side entry SPE seat with hard insert.
- Thermoplastic inserted ring
- Graphite ring
- Anti-extrusion ring
- O-ring
- O-ring or grease guard
Side entry DPE seat with hard insert.
- Thermoplastic inserted ring
- Graphite ring
- Anti-extrusion ring
- O-ring
Side entry DPE seat with hard insert, Lip seal.
- Thermoplastic inserted ring
- Graphite ring
- Lip seal
- Retainer ring
