Flowtite Technology: Continuous Filament Winding
High-performance GRP pipe manufacturing technology designed for structural efficiency and long-term reliability.
GRP pipes manufactured according to Flowtite technology have a structural sandwich build-up produced using a continuous filament winding process. High-strength continuous glass fibres are precisely oriented to resist hoop stresses caused by internal pressure, while chopped fibres contribute to resistance against axial stresses, impact, and handling loads.
The structural laminate consists of heavily reinforced inner and outer skins, separated by a compact, reinforced, silica-filled core that provides optimal bending stiffness. Together with dedicated protective layers, this construction enables the pipe to withstand high internal pressures while maintaining excellent long-term stiffness and dimensional stability.
Wall structure of a filament wound GRP pipe
- Inner protective layer
- Inner structural layer
- Core layer
- Outer structural layer
- External protective layer
Hover or click a layer to explore the structure
Wall structure of a filament wound GRP pipe (Flowtite technology)
Manufacturing of Flowtite GRP pipes
GRP pipes based on Flowtite technology are produced using a continuous advancing mandrel process. This process enables the use of continuous glass fibre reinforcements in the circumferential direction. For a pressure pipe or buried conduit, the principal stress occurs circumferentially; therefore, incorporating continuous reinforcements in this direction results in a higher performing product at a lower cost.
The filament winding manufacturing machine consists of a continuous steel band mandrel supported by beams arranged in a cylindrical shape. As the beams rotate, friction pulls the steel band around, while a roller bearing allows the band to move longitudinally so that the entire mandrel advances continuously in a spiral path towards the exit assembly. As the mandrel rotates, all composite materials are metered onto it in precise amounts with the help of electronic sensors. First, a mould release film is applied, followed by various forms and patterns of glass fibres embedded in a polyester resin matrix. The structural layers are made solely of glass and resin, whereas the core layer contains pure silica. Once the pipe has been formed on the mandrel, it is cured and later cut to the required length. The ends of the pipe section are then calibrated to ensure a perfect fit with the coupling.
Technical data GRP pipes produced with Flowtite technology
| Main materials | resin, glassfibers, sand |
|---|---|
| Main materials | resin, glassfibers, sand |
| Operating temperature | -50 °C to +70 °C, higher temperatures may be considered for individual projects |
| Standard lengths | 12, 6, and 3 m, other lengths on request |
| Pressure range | PN 1-32 |
| Corrosion protection | none needed, as materials used are inherently resistant to corrosion |
| Hydraulic roughness | k = 0.029 mm (Colebrook-White) |
| Water jetting resistance | tested according to DIN 19523 |
Key benefits of the
Flowtite technology
Continuous circumferential glass fibres provide superior hoop strength, while chopped fibres enhance axial reinforcement and impact resistance – ensuring reliable performance under demanding conditions.
A compact, silica-filled core increases wall thickness and bending stiffness, making Amiblu Flowtite pipes ideal for underground installations with long-term structural demands.
Reinforcing materials are placed exactly where stresses are highest, resulting in high performance with optimised material consumption and reduced overall cost.
Electronic metering and the continuous mandrel process ensure uniform laminate structure, precise geometry, and reproducible quality from one pipe section to the next.
Flowtite licensees worldwide
Flowtite technology is available around the globe through our exclusive licensing program. With nine trusted manufacturing partners worldwide, we ensure consistent quality, expertise, and support across all markets.
Explore our global network of Flowtite licensees in the map below.
