FRP / GRP
Piping & Fittings Manufacturer · Supplier · Exporter
Filament wound and hand lay-up FRP/GRP pipes, fittings, flanges, elbows, tees, reducers, and stub ends in isophthalic polyester, vinyl ester, epoxy, and phenolic resin systems. DN 25–1200 (1″–48″). Compliant with ASTM, AWWA, ISO 14692, DIN, BS EN standards. Serving chemical, oil & gas, water, desalination, power, and marine sectors globally.
FRP/GRP Products — Full Range
All products manufactured under strict quality control with full material traceability, hydrostatic test certificates, dimensional inspection reports, and lamination inspection records. Third-party inspection (SGS, TÜV, BV) available on request.
Continuous filament wound pipes using CNC-controlled helical and hoop winding patterns. Optimum fibre-to-resin ratio for maximum hoop and axial strength. Available in all five resin systems. The most common FRP pipe manufacturing method for industrial and infrastructure service.
- Size RangeDN 25 – DN 1200 (1″ – 48″)
- Pressure RatingsPN 6 / PN 10 / PN 16 / PN 25 / custom (up to 50 bar)
- Wall StructureInner liner (C-glass / ECR / nexus veil) + structural laminate (E-glass) + optional UV outer coat
- Liner Thickness2.0 – 3.0 mm (resin-rich, chemically resistant)
- Winding Angle±55° (standard) · ±75° (pressure pipe) · Hoop + helical combined
- Resin SystemsIsophthalic · Vinyl Ester · Epoxy · Orthophthalic · Phenolic
- FibreE-glass (standard) · ECR-glass (acid/alkali) · C-glass (liner) · Carbon (special)
- Stiffness ClassSN 1250 / SN 2500 / SN 5000 / SN 10000 (per ISO 7685 / ASTM D2412)
- Joint TypesBell & spigot (GJ / BJ) · Butt & wrap laminated · Flanged · Threaded
- LengthsStandard 6 m / 12 m · Custom lengths to 18 m on request
- Temp. Range-40°C to +110°C (ISO) · up to +200°C (phenolic resin)
- Hazen-Williams C150 (smooth bore — no corrosion-related roughness increase over life)
- Density1.7 – 2.0 g/cm³ (vs. 7.85 g/cm³ steel) — approx. ¼ the weight
Manual or semi-automated hand lay-up construction for large diameter, complex geometry, or bespoke wall build-ups. Used for large tanks, ducts, chimney liners, and large-bore pipes where filament winding is impractical. Allows incorporation of core materials and custom laminates.
- Size RangeDN 400 – DN 3000+ (bespoke)
- Wall Build-upChopped strand mat (CSM) + woven roving (WR) + stitched fabric
- LinerNexus veil / C-glass surfacing tissue + resin-rich inner layer
- Structural LayerAlternating CSM + WR to designed wall thickness
- Core OptionsPVC foam · Balsa · Honeycomb (for stiffness increase)
- Resin SystemsIso · VE · Epoxy · Orthophthalic
- Glass Content25–35% by weight (vs. 55–70% filament wound)
- ApplicationsDuct, chimney liners, fume extraction, large tanks/vessels, custom shapes
- Temp. RangeUp to +150°C (VE) · +200°C (phenolic)
Filament Wound FRP Pipe — Standard Dimensions & Pressure Ratings
Wall thickness increases with pressure class. All values for vinyl ester resin at ambient temperature. Higher temperatures require wall thickness de-rating — consult engineering datasheet.
| DN / NPS | OD (mm) | PN 6 Wall (mm) | PN 10 Wall (mm) | PN 16 Wall (mm) | PN 25 Wall (mm) | Std. Length (m) | Weight PN10 (kg/m) |
|---|---|---|---|---|---|---|---|
| DN 25 / 1″ | 33 | 3.5 | 4.0 | 5.0 | 6.5 | 6 | 0.5 |
| DN 40 / 1½″ | 48 | 3.5 | 4.5 | 5.5 | 7.0 | 6 | 0.8 |
| DN 50 / 2″ | 60 | 4.0 | 5.0 | 6.0 | 8.0 | 6 | 1.1 |
| DN 80 / 3″ | 89 | 4.5 | 5.5 | 7.0 | 9.5 | 6 | 2.0 |
| DN 100 / 4″ | 114 | 4.5 | 6.0 | 7.5 | 10.5 | 6 | 2.9 |
| DN 150 / 6″ | 168 | 5.0 | 6.5 | 8.5 | 12.0 | 6 / 12 | 5.2 |
| DN 200 / 8″ | 219 | 5.5 | 7.5 | 10.0 | 14.0 | 6 / 12 | 8.4 |
| DN 250 / 10″ | 273 | 6.0 | 8.0 | 11.0 | 15.5 | 6 / 12 | 12.5 |
| DN 300 / 12″ | 324 | 6.5 | 9.0 | 12.0 | 17.0 | 6 / 12 | 17.0 |
| DN 400 / 16″ | 426 | 7.5 | 10.5 | 14.5 | 20.0 | 6 / 12 | 28.5 |
| DN 500 / 20″ | 530 | 8.5 | 12.0 | 16.5 | 23.0 | 6 / 12 | 43.5 |
| DN 600 / 24″ | 630 | 9.5 | 13.5 | 18.5 | — | 6 / 12 | 61.0 |
| DN 800 / 32″ | 838 | 11.0 | 16.0 | 22.0 | — | 6 / 12 | 105 |
| DN 1000 / 40″ | 1042 | 13.0 | 19.0 | 26.0 | — | 6 / 12 | 162 |
| DN 1200 / 48″ | 1245 | 15.5 | 22.0 | 31.0 | — | 6 / 12 | 234 |
Wall thickness values are indicative for vinyl ester resin, E-glass filament wound construction at ambient temperature (23°C). De-rate by 20–40% for service temperatures above 60°C. Sizes outside this range available on request. Weights ±10% depending on resin system and wall build-up.
Filament wound or hand lay-up GRP elbows for change of direction. Available in long radius (LR = 1.5D) and short radius configurations. Matched to pipe wall thickness and resin system for full system continuity.
- Types45° LR · 90° LR · 90° SR · Mitre (segmented for large bore)
- Size RangeDN 25 – DN 1200
- Pressure RatingPN 6 / PN 10 / PN 16 (matched to pipe rating)
- ConstructionFilament wound (DN ≤ 600) · Hand lay-up / segmented (DN > 600)
- End ConnectionButt & wrap · Flanged · Bell & spigot
- Resin SystemsISO · VE · Epoxy · Ortho · Phenolic
- Radius (LR)R = 1.5 × DN
Concentric and eccentric reducers for connecting GRP pipes of different diameters. Manufactured by filament winding or hand lay-up. Eccentric reducers used for pump suction lines and drainage gradient maintenance.
- TypesConcentric (CON) · Eccentric (ECC)
- Size RangeDN 50×25 to DN 1200×800
- Pressure RatingPN 6 / PN 10 / PN 16
- ConstructionFilament wound · Hand lay-up
- End ConnectionButt & wrap · Flanged · Spigot
- Wall ThicknessMatched to larger diameter pipe rating
Equal and reducing tees for flow branching. Branch reinforcement laminate applied at junction to restore full pressure rating. Available in standard and custom branch angles (90° standard; 45° on request).
- TypesEqual tee · Reducing tee · Lateral (45°) tee · Y-piece
- Size RangeDN 50×50 to DN 1200×800
- Pressure RatingPN 6 / PN 10 / PN 16
- ConstructionFilament wound · Hand lay-up · Moulded (small sizes)
- Branch Reinf.Hand lay-up reinforcement pad at junction (ASME RTP-1 calc.)
- End ConnectionButt & wrap · Flanged · Spigot
GRP stub ends used with metal or GRP lap joint backing rings — enables pipe rotation for bolt-hole alignment without rotating the pipe itself. Provides a cost-effective GRP-to-GRP or GRP-to-steel transition joint.
- Size RangeDN 25 – DN 1200
- Pressure RatingPN 6 / PN 10 / PN 16
- Backing Ring MOCSS 316 / SS 304 · CS (hot dip galv.) · GRP ring
- Face TypeFlat face (FF) — standard for GRP flanged joints
- Resin SystemsISO · VE · Epoxy · Ortho
- Flange DrillingASME B16.5 · DIN 2501 · EN 1092-1 · BS 4504
Couplings for joining two pipe spigot ends and saddles for branch connections onto existing pipe runs without cutting out a tee. Repair couplings also available for in-situ repair of damaged GRP pipework.
- Coupling TypesBell & spigot (GJ) · Butt & wrap laminated · Mechanical (Viking Johnson type)
- Saddle TypesFull encirclement saddle · Half saddle (low pressure) · Reinforced boss outlet
- Size RangeDN 50 – DN 1200
- Pressure RatingPN 6 / PN 10 (saddles) · Full pipe rating (couplings)
- End ConnectionButt & wrap · Flanged outlet
GRP Fittings — Size & Pressure Range Availability
| Fitting Type | Size Range (DN) | PN 6 | PN 10 | PN 16 | Construction Method | Standard |
|---|---|---|---|---|---|---|
| 45° Elbow (LR) | 25 – 1200 | ✓ | ✓ | ✓ | FW (≤600) · HL (>600) | ASTM D2996 / DIN 16966 |
| 90° Elbow (LR) | 25 – 1200 | ✓ | ✓ | ✓ | FW (≤600) · HL (>600) | ASTM D2996 / DIN 16966 |
| Reducer CON | 50×25 – 1200×800 | ✓ | ✓ | ✓ | FW / Hand lay-up | ASTM D2996 / DIN 16966 |
| Reducer ECC | 50×25 – 1200×800 | ✓ | ✓ | ✓ | FW / Hand lay-up | ASTM D2996 / DIN 16966 |
| Equal Tee | 50 – 1200 | ✓ | ✓ | ✓ | FW / Hand lay-up | ASTM D2996 / ISO 14692 |
| Reducing Tee | 80×50 – 1200×800 | ✓ | ✓ | ✓ | Hand lay-up | ASTM D2996 / ISO 14692 |
| Stub End | 25 – 1200 | ✓ | ✓ | ✓ | FW / Hand lay-up | DIN 16966 |
| End Cap | 25 – 1200 | ✓ | ✓ | ✓ | FW / Hand lay-up | DIN 16966 |
| Coupling (Spigot) | 50 – 1200 | ✓ | ✓ | — | FW / Hand lay-up | DIN 16966 |
| Saddle (full encirclement) | 100 – 1200 | ✓ | ✓ | — | Hand lay-up | Manufacturer spec |
| Y-piece / Lateral | 80 – 800 | ✓ | ✓ | On request | Hand lay-up | Custom design |
FW = Filament Wound · HL = Hand Lay-up. All fittings hydrostatically tested to 1.5 × rated pressure. Butt & wrap joints require site lamination — joint kits (resin, glass, instructions) supplied with every order.
Contact moulded (hand lay-up) or filament wound GRP flanges. Always supplied as flat face (FF) — full-face gasket mandatory. GRP-to-metal flange joints require full-face gasket and reduced bolt torque to prevent flange cracking. Flange drilling matches ASME, DIN, EN, or BS bolt circles.
- TypesIntegral (laminated to pipe) · Loose backing ring (stub end type) · Blind flange
- Face TypeFlat Face (FF) — ALWAYS flat face for GRP. No raised face on GRP flanges.
- Size RangeDN 25 – DN 1200
- Pressure RatingPN 6 / PN 10 / PN 16
- DrillingASME B16.5 (ANSI) · DIN 2501 (PN series) · EN 1092-1 · BS 4504
- Resin SystemsISO · VE · Epoxy · Ortho
- Gasket Req.Full-face EPDM / NBR / PTFE — min. 3 mm thickness
- Bolt TorqueMax. 40–80 Nm (DN 50–300) — torque wrench mandatory, never pneumatic impact
- Backing RingSS 316 / GRP ring for stub end (lap joint) assemblies
- Blind FlangeAvailable DN 25 – DN 600 for system isolation
- ConstructionHand lay-up (chopped mat + woven roving) min. 8 mm flange thickness
GRP Flange Bolting — Maximum Torque Values
GRP flanges are brittle in compression — over-torquing causes cracking and leakage. Never use pneumatic impact wrenches. Torque wrench mandatory. Tighten in star pattern (crosswise), 3 passes.
| DN / NPS | No. of Bolts | Bolt Dia. | Max. Torque (Nm) | Gasket Type | Note |
|---|---|---|---|---|---|
| DN 50 / 2″ | 4 | M16 | 40 | Full face EPDM 3 mm | Tighten in 2 passes to max |
| DN 80 / 3″ | 4 | M16 | 45 | Full face EPDM 3 mm | Star pattern, 3 passes |
| DN 100 / 4″ | 8 | M16 | 45 | Full face EPDM 3 mm | Star pattern, 3 passes |
| DN 150 / 6″ | 8 | M20 | 55 | Full face EPDM 4 mm | Star pattern, 3 passes |
| DN 200 / 8″ | 8 | M20 | 60 | Full face EPDM 4 mm | Star pattern, 3 passes |
| DN 250 / 10″ | 12 | M24 | 70 | Full face EPDM / PTFE 4 mm | Star pattern, 3 passes |
| DN 300 / 12″ | 12 | M24 | 80 | Full face EPDM / PTFE 4 mm | Star pattern, 3 passes |
| DN 400 / 16″ | 16 | M27 | 90 | Full face EPDM 5 mm | Star pattern, 3 passes |
| DN 600 / 24″ | 20 | M30 | 100 | Full face EPDM 6 mm | Star pattern, 3 passes |
Continuous-pull pultruded structural profiles in E-glass / isophthalic or vinyl ester resin systems. Consistent cross-section, high fibre volume, excellent mechanical properties. Non-conductive, non-magnetic, corrosion-free alternative to structural steel in aggressive environments.
- Profile TypesFlat bar · Angle (equal & unequal) · Channel (C / U) · I-beam · T-section · Tube (round & square) · Grating
- Resin SystemsIsophthalic polyester (standard) · Vinyl ester (chemical / fire rated)
- Standard LengthsUp to 12 m standard · Custom lengths on request
- Fibre Content50–70% by weight (high Vf — high mechanical strength)
- Tensile Strength (axial)≥ 240 MPa (flat bar) · ≥ 200 MPa (I-beam web)
- Flexural Modulus17–23 GPa (vs. ~200 GPa steel — lighter, lower stiffness)
- Density1.8–2.0 g/cm³ (¼ weight of steel)
- Surface FinishNatural grey / green · UV-stabilised topcoat · Anti-slip grit surface (grating)
- Fire RatingClass B2 (DIN 4102) standard · Class B1 / Class 1 FR grades (halogen-free)
- ApplicationsCable trays · Handrails · Structural supports · Walkway grating · Pump bases · Pipe supports · Chemical plant structures
Pultruded GRP — Mechanical Properties vs. Structural Steel
| Property | Pultruded GRP (ISO resin) | Pultruded GRP (VE resin) | Mild Steel S235 | SS 304 | Advantage |
|---|---|---|---|---|---|
| Density (g/cm³) | 1.85 | 1.88 | 7.85 | 8.0 | GRP = ¼ weight |
| Tensile Strength (MPa) | 170–240 | 200–270 | 360–510 | 485–690 | Steel stronger but 4× heavier |
| Flexural Modulus (GPa) | 17–21 | 18–23 | 210 | 193 | Steel stiffer — GRP deflects more |
| Compressive Strength (MPa) | 180–250 | 200–280 | 235–355 | 170–310 | Comparable — check buckling |
| Corrosion Resistance | Excellent | Superior | Poor (paints needed) | Good | GRP wins — no paint, no rust |
| Electrical Conductivity | Non-conductive | Non-conductive | Conductive | Conductive | GRP safe near live equipment |
| Thermal Conductivity (W/mK) | 0.3–0.4 | 0.3–0.4 | 50 | 16 | GRP = better insulator |
| Maintenance Cost (25yr) | Very low | Very low | High (painting, inspection) | Moderate | GRP = lower whole-life cost |
Resin Selection Guide
Resin system is the most critical specification for FRP/GRP piping — it determines chemical resistance, temperature capability, fire performance, and cost. Select based on the most aggressive chemical in your process stream.
Resin Chemical Resistance Quick Reference
✓ = Recommended · L = Limited / consult full resistance table · ✗ = Not recommended. Always verify with full ISO 14692 / ASTM chemical resistance chart for specific concentration and temperature before final specification.
| Chemical / Medium | Concentration | Orthophthalic | Isophthalic | Vinyl Ester | Epoxy | Phenolic |
|---|---|---|---|---|---|---|
| Water (raw / potable) | — | ✓ | ✓ | ✓ | ✓ | ✓ |
| Seawater / brine | — | L | ✓ | ✓ | ✓ | L |
| Hydrochloric Acid (HCl) | Up to 37% | ✗ | L (≤25°C) | ✓ | L | ✓ |
| Sulphuric Acid (H₂SO₄) | Up to 70% | ✗ | L (≤20%) | ✓ | L (≤30%) | ✓ |
| Nitric Acid (HNO₃) | Up to 30% | ✗ | ✗ | L (dilute) | ✗ | L |
| Sodium Hydroxide (NaOH) | Up to 40% | ✗ | L (≤30°C) | ✓ | ✓ | L |
| Sodium Hypochlorite (NaOCl) | Up to 15% | ✗ | L | ✓ | L | ✓ |
| Crude Oil / Hydrocarbons | — | L | L | ✓ | ✓ | ✓ |
| Sewage / wastewater | — | ✓ | ✓ | ✓ | ✓ | ✓ |
| Ferric Chloride (FeCl₃) | All conc. | ✗ | L | ✓ | ✓ | ✓ |
| Phosphoric Acid (H₃PO₄) | Up to 85% | ✗ | ✓ (≤50%) | ✓ | ✓ | ✓ |
| Acetic Acid | Up to 50% | ✗ | L | ✓ | ✓ | ✓ |
| Flue Gas (FGD scrubbers) | — | ✗ | L | ✓ (preferred) | ✓ | ✓ |
| Mine tailings / slurry | — | ✗ | L | ✓ | ✓ | L |
Applications — Key Sectors
FRP/GRP piping systems deliver 30–50 year service life in environments where carbon steel corrodes within 2–5 years. The whole-life cost advantage is typically 2–4× over metallic piping in corrosive service.
FRP/GRP vs. Steel
A direct technical and economic comparison. FRP/GRP does not replace steel in all applications — but in corrosive, weight-sensitive, or electrically isolated service it is the superior choice on total cost of ownership.
| Property / Factor | FRP / GRP (VE resin) | Carbon Steel (CS) | SS 316L | HDPE | Verdict |
|---|---|---|---|---|---|
| Density (g/cm³) | 1.85 | 7.85 | 8.0 | 0.95 | HDPE lightest; FRP ¼ of steel |
| Corrosion Resistance | Excellent (no metal) | Poor (requires coating) | Good | Good | FRP / HDPE / SS 316 win |
| Max. Service Temp. | +110°C (VE) · +120°C (Epoxy) | +450°C (carbon steel) | +450°C | +60°C (pressure) | Steel wins for high temp |
| Pressure Capability | Up to PN 25 (50 bar) | Essentially unlimited | Essentially unlimited | PN 10 (≤60°C) | Steel wins for high pressure |
| Tensile Strength (MPa) | 170–270 (hoop) | 360–510 | 485–690 | 20–30 | Steel stronger; FRP lighter |
| Hazen-Williams C | 150 (permanent) | 100–130 (decreases) | 130–140 | 150 | FRP / HDPE — lowest friction |
| Installation Weight (DN300) | ~17 kg/m | ~78 kg/m | ~78 kg/m | ~12 kg/m | FRP much easier to handle |
| Electrical Conductivity | Non-conductive | Conductive | Conductive | Non-conductive | FRP/HDPE safer near live equip. |
| Cathodic Protection | Not required | Required (buried / offshore) | Not required | Not required | FRP saves CP system cost |
| External Painting | Not required (UV coat only) | Mandatory (ongoing) | Not required | Not required | FRP / SS / HDPE win |
| Design Life | 50+ years | 10–25 years (corrosive service) | 25–40 years | 30–50 years | FRP comparable or better |
| Initial Material Cost | Medium–High | Low | High | Low–Medium | CS cheapest upfront |
| Whole Life Cost (50yr) | Lowest (corrosive service) | Highest (corrosion, maintenance) | Medium | Low–Medium | FRP wins in corrosive service |
| Fire Performance | L (limited — phenolic for FR) | Good structural | Good structural | Burns / melts | Steel best; phenolic FRP acceptable |
| UV Resistance | L (UV gelcoat required) | Good (painted) | Good | L (UV grades) | All need UV protection |
Export Standards
All FRP/GRP products supplied with full quality documentation — lamination records, hydrostatic test reports, dimensional inspection, raw material certifications, and third-party inspection reports. DNV / Lloyd's / BV product certificates available.
Export Market — Preferred Standards Guide
| Export Region | Pipe Standard | Fittings Std. | Flange Drilling | Design Std. | Certification |
|---|---|---|---|---|---|
| USA / Canada | ASTM D2996 / AWWA C950 | ASTM D2996 | ASME B16.5 (ANSI) | ASME RTP-1 | NSF 61 (potable water) · UL (fire) |
| Europe (EU/EEA) | BS EN 13121 / DIN 16965 | DIN 16966 | EN 1092-1 (PN) | BS EN 13121 | CE Mark (PED 2014/68/EU) · WRAS (UK water) |
| Middle East (Oil & Gas) | ISO 14692 / ASTM D2996 | ISO 14692-3 | ASME B16.5 · ANSI | ISO 14692 · NORSOK | Aramco / ADNOC / PDO specs · DNV/BV cert |
| Middle East (Water) | AWWA C950 / DIN 16965 | DIN 16966 | ANSI / DIN 2501 | AWWA M45 | SASO (Saudi) · ESMA (UAE) |
| Africa | BS 6464 / AWWA C950 | BS EN 13121-3 | BS 4504 / EN 1092-1 | BS EN 13121 | SABS (SA) · EN 10204 3.1 |
| Marine / Offshore | ISO 14692 / NORSOK M-622 | ISO 14692-3 | ASME B16.5 | ISO 14692 · IMO A.753 | DNV · Lloyd's · BV · IMO class cert |
Tell us resin system, size range, pressure class, service medium, and export standard — we'll respond within 24 hours with pricing and lead time.
- Full lamination records and raw material batch traceability with every order
- Hydrostatic test (1.5 × PN rating) certificates supplied as standard
- Dimensional inspection report per ASTM / DIN / ISO standard
- Third-party inspection — DNV, Lloyd's, BV, SGS, TÜV on request
- CE marking (PED 2014/68/EU) for European export
- DNV / Lloyd's product type approval certificates available
- Resin chemical resistance confirmation for your specific medium
- Joint kits (resin, glass tape, instructions) supplied with pipe orders
- Export packing — fumigated wooden crates, sea freight & air freight ready
