4inch RO FRP Housing End Cap 101.6 mm

Description

• Material: Glass-reinforced polypropylene (PP-GF)

• Pressure Rating: Up to 10 bar / 145 psi

• Features: Dual O-rings for superior sealing; designed for FRP RO vessels

• Use: Permanent end closure for 4″ vessel openings; ideal for high-pressure water treatment systems

• A 4″ end plug for an FRP pressure vessel (like for RO membranes) is designed to fit into a 4‑inch nominal threaded port — that means the vessel opening it seals is 4″ (10.16 cm) in diameter

• FRP housings the O‑rings are usually sized with:

  • Inner diameter around ~104–110 mm (to match the plug shaft)

  • Cross‑section thickness ~5–7 mm (for good sealing and compression)

  • Typical O-ring Material for FRP End Plugs

    Material	Properties	Use Case
    EPDM (Ethylene Propylene Diene Monomer)	Flexible, UV-resistant, good for hot/cold water, chemical resistant to chlorine	Most common for potable water FRP vessels and membrane housings
    NBR (Nitrile / Buna-N)	Resistant to oils, good for water, moderate temperature	Sometimes used in industrial water systems
    Viton (FKM)	High chemical and temperature resistance	Rare for standard potable water; used for harsh chemical applications