FRP Membrane Housing

Choose FRP when corrosion resistance, weight and cost come first: the composite shell never rusts, even in seawater, and weighs about a quarter of the equivalent stainless vessel. Choose stainless steel (SS304 / SS316L) for hot-water sanitisation, sanitary polished finish or pharmaceutical duty. Many plants run FRP on the first RO pass and stainless on the sanitary polishing stages — read the full comparison in our FRP vs stainless steel guide.

Match the class to the maximum pressure the vessel will ever see, including pump dead-head and any back pressure — not just the normal operating point. Most brackish-water RO runs comfortably on 300 psi (2.1 MPa); seawater and high-recovery systems need 450 psi and above, and we build 600 and 1000 psi vessels on request. Every vessel is hydro-tested before shipment.

The limit is the resin system, not the glass fibre. Our standard vessels are rated for continuous service from 20 F to 120 F (-7 C to 49 C). If your process runs hotter, tell us at enquiry stage — we will quote a higher-temperature resin or recommend a stainless steel vessel instead.

Yes. Head sealing assemblies, sealing plates, thrust rings, adapters, end caps, locking plates, permeate outlets and mounting saddles or clamps can all be supplied with the vessel, so your RO rack arrives complete. SS304 / SS316L adapters are available where the wetted parts must be metallic.

Trial orders from 1 piece are welcome. Standard 4040 and 8040 FRP housings ship in about 10 - 20 working days; custom lengths, ports and pressure classes take 20 - 30 working days. Send your element size, element count and feed-water data and we will confirm the model and quote.