Let our team help you select the right product
Talk to our experts, we can help you meet your requirements and provide assistance for your next project.
FRP PIPE
Fiberglass pipes are lightweight and economical pipes that can replace steel, iron, and concrete pipes.The core advantages of FRP continuously wound pipe lie in its high strength, high rigidity, excellent corrosion resistance, superior hydraulic performance, superior leak resistance, and the economic and length advantages afforded by continuous production. It seamlessly integrates materials science with advanced manufacturing processes, offering a high-performance, cost-effective, and environmentally friendly modern engineering piping solution, particularly suited for long-distance, high-flow, and corrosive transport.
| Nominal diameter | 100 mm – 4000 mm (round); custom rectangular/oval cross-sections available |
| Wall thickness | Sized to span and pressure class; reinforcing ribs required above 1000 mm side length |
| Operating pressure | Low-pressure to slightly negative/positive systems (confirm your system's static pressure) |
| Operating temperature | -40°C to 80°C (organic type, standard resin) |
| Resin systems available | Standard polyester (general corrosive fume), vinyl ester / epoxy (higher chemical load or temperature) |
| Joint types | Socket bonding (inorganic type), flanged bolted connection (organic type) |
| Surface finish | Smooth bore, resin-rich interior liner |
Products Description
As one of the FRP duct manufacturers supplying fume and smoke exhaust systems to chemical plants, power stations, and cleanroom facilities, Pipezy produces fiberglass reinforced plastic duct engineered specifically for corrosive, high-temperature, and fire-sensitive airflow applications — not general-purpose sheet metal converted to a "composite" spec sheet.
FRP duct (fiberglass reinforced plastic duct) is a resin-and-glass-fiber composite ventilation pipe used to move air, gas, and fume in industrial and commercial systems. It falls into two families: organic FRP duct (resin-based) and inorganic FRP duct (magnesium oxychloride cement-based). Pipezy manufactures and sells organic FRP duct, the type specified for most corrosive-fume and chemical-exhaust applications — as opposed to lighter-duty fiberglass ventilation tubing used in general HVAC runs, which does not need the same chemical-resistant liner or fire-rated construction.
1. Lightweight and High Strength
FRP duct weighs only 1/10 of concrete duct and roughly 30% of steel duct at the same specification, cutting transport and rigging cost. Compressive strength reaches 65 MPa (organic type), with strong impact resistance.
2. Corrosion Resistance and Durability
Organic-type fiberglass reinforced plastic duct resists acid, alkali, and salt corrosion — this is the property that makes it the standard choice over coated steel for corrosive gas exhaust in chemical and textile plants.
3. Environmental Adaptability
Wide operating temperature range (-40°C to 80°C), resistant to damp heat and freeze-thaw cycling — relevant for both outdoor stacks and indoor process exhaust.
4. Excellent Fluid Performance
Smooth inner wall, low resistance, roughly 10% higher flow rate than steel duct at the same specification, with no fluid residue or scaling buildup over long-term use.
5. Economic Efficiency
Lower overall lifecycle cost, no anti-corrosion maintenance required — and the cost advantage of FRP duct over steel or concrete grows with diameter.
Buyers evaluating FRP duct are usually comparing it against three alternatives. Typical industry-level differences:
| Factor | FRP Duct | Galvanized Steel | PVC Duct | Stainless Steel |
|---|---|---|---|---|
| Corrosion resistance (acid/alkali fume) | Excellent — resin matrix is the barrier, not a coating | Poor without ongoing coating maintenance | Good for mild chemicals, degrades under high heat | Good, but chlorides can cause pitting |
| Relative weight | ~30% of steel | Baseline | Lighter than FRP, but limited pressure/size range | Heavier than FRP |
| Max practical operating temperature | Typically up to ~120°C depending on resin | Higher, but coating fails first | Generally lower (~60°C) | Higher |
| Expected service life (corrosive service) | 20–30+ years, minimal maintenance | 5–10 years before major recoating/replacement | 10–15 years, embrittlement over time | 15–25 years |
| Maintenance | No recoating, no cathodic protection needed | Periodic recoating, inspection | Low, but UV/thermal degradation | Periodic inspection for pitting |
| Typical initial cost vs. steel | Moderate to higher upfront | Lowest upfront | Lowest for small diameters | Highest upfront |
Manufacturing organic FRP duct:
Winding process — resin impregnates fiberglass, which is wound layer by layer on a rotating mandrel; a sand layer adds rigidity. This is the same core process used to build our Continuously Wound Pipe and FRP Continuous Winding Pipe lines.
Hand lay-up process — fiberglass cloth is laid on the mold surface and coated with resin, stacked in multiple layers, cured, and demolded — used for irregularly shaped duct fittings, elbows, and transitions.
Resin selection follows the same logic as our piping systems: standard polyester resin for general corrosive fume service, with upgrades available through our Unsaturated Polyester Resins for Fiberglass Reinforced Plastics and FRP Fiber material options for higher-temperature or higher-chemical-load runs.
Buyers specifying duct for semiconductor fabs, cleanrooms, and fume/smoke exhaust systems often need to confirm compliance with FM Approval Standard 4922 (fire performance of fume and smoke exhaust duct systems, allowing installation without automatic sprinkler protection where permitted) and FM 4910 (cleanroom material flammability, used in semiconductor and pharmaceutical facilities). These standards exist because uncontrolled duct fire spread in a fab or scrubber system is a serious life-safety and property risk, so specifiers are right to ask for documentation, not just a marketing claim.
If your project specification requires FM 4922/4910-compliant construction, tell our engineering team the application, duct size, and governing standard, and we will confirm current test documentation and certification status for the specific configuration you need before you finalize your order — rather than assuming any FRP duct on the market automatically qualifies. Duct systems referencing these standards are also typically cross-checked against NFPA 318 (semiconductor fabrication facility protection) and ASTM E-136 combustibility testing, which our team can walk through with you.
Our FRP duct and fiberglass reinforced plastic duct systems are engineered for demanding industrial applications:
Fume Exhaust Systems — chemical processing plants and laboratories.
Flue Gas Desulfurization (FGD) — scrubber outlet ducts in power plants.
Semiconductor Manufacturing — acid and alkali exhaust ventilation, where FM 4910 cleanroom criteria often apply.
Pulp & Paper — bleach plant ventilation and recovery boiler duct runs.
Water Treatment — odor control ductwork (H₂S resistance).
General Commercial Ventilation — lighter-duty fiberglass ventilation tubing for non-corrosive airflow where full chemical-grade FRP duct is not required.
Connection method — socket bonding (inorganic type) or flange bolts (organic type), sealed with 8501 adhesive strip. Matching Fiberglass Flanges are available from the same production line to keep resin systems and tolerances consistent across the joint.
Reinforcement requirements — reinforcing ribs required when the side length exceeds 1000 mm, with longitudinal spacing ≤1250 mm.
Support and hanger spacing — for horizontal installation with a long side ≤2000 mm, support spacing should be ≤2 m, with hanger diameter ≥10 mm.
We provide complimentary duct layout review, structural calculations for supports, and installation supervision. Submit your P&ID or duct layout for engineering recommendations.
Wall thickness tolerance — deviation of -1 to 0 mm when the side length is ≤300 mm.
Air leakage detection — light leakage testing required; zero light leakage at joints is the acceptance standard.
Inorganic-type defect prevention — controlled slurry uniformity, curing temperature, and humidity to avoid flange deformation.
Download the full duct catalog.
Q: How do you handle thermal expansion in long duct runs?
A: FRP has a coefficient of thermal expansion of 1.0–1.5 × 10⁻⁵ in/in/°F (lower than PVC). For runs exceeding 50 ft, we specify expansion joints (bellows type or packed slip joints) every 30–40 ft, with expansion calculated against your actual operating temperature range and provided in installation drawings.
Q: Can FRP duct support its own weight over long spans?
A: Yes, with proper design. FRP is about 1/4 the weight of steel but has a lower modulus of elasticity, so we engineer wall thickness and rib spacing (for large diameters) to limit deflection to L/240 or L/360 as required, recommending trapeze supports or bonded structural angles for spans over 10 ft.
Q: What about lightning protection for outdoor FRP stacks?
A: FRP is non-conductive and needs separate lightning protection — we recommend copper grounding conductors external to the duct with bonding jumpers at joints, and can design stacks with integral lightning-rod attachment points.
Q: How do you ensure airtight joints in negative pressure systems?
A: We use flanged connections with full-face gaskets (not ring gaskets) and a proper bolt torque sequence. For severe vacuum service (>15" WG), we specify butt-wrap field joints or adhesive-bell joints with secondary mechanical locking, and light-leak test every joint before startup.
Q: Is FRP duct compatible with VAV controls and fire dampers?
A: Yes. We supply FRP dampers (volume control and fire-rated) that integrate with BMS systems, with fusible-link fire dampers (165°F or 212°F) and electric actuator options, plus standard airflow measurement stations at flanged connections.
Q: Does your FRP duct meet FM 4922 or FM 4910 requirements?
A: It depends on the exact configuration, resin system, and size your project specifies. Send us the governing standard and application (fume exhaust vs. cleanroom) and our engineering team will confirm current documentation before you finalize the order — we won't tell you a duct is compliant without checking the specific build first.
Q: What is the lead time for custom FRP ductwork?
A: Standard diameters (12"–48") typically ship in 3–4 weeks; large diameters (>60") or complex fittings run 6–8 weeks. Emergency expedite is available for critical shutdowns, and we hold raw-material inventory for common resin systems to shorten lead times.
Send us your airflow requirements, governing standard, and drawings — our team will recommend the most cost-effective resin system and duct design. Get a quote for your project.
Let our team help you select the right product
Talk to our experts, we can help you meet your requirements and provide assistance for your next project.