Filament Winding Grade Resin data sheet (PDF)Ask for a quote
What winding asks of a resin
On a filament-winding line, roving is drawn through a resin bath, wiped to the right resin content and laid onto a rotating mandrel. The resin must wet the roving in the moments it spends in the bath, and remain workable for as long as it takes to wind and consolidate the whole part. For a small pipe that is short; for a large tank it can be long.
Those two needs — fast wet-out and a long working window — define a winding grade.
Line and product questions
Share with the enquiry
- Pipe diameter and length, or tank diameter and height.
- Wind pattern, line speed and bath size.
- Workshop temperature through the year.
- The medium the pipe or tank will carry, and its temperature and pressure.
- Liner construction, and whether it uses a different resin.
- The governing pipe or tank specification.
Where SPR 301 FW fits
SPR 301 FW is the non-thixotropic isophthalic grade the catalogue lists for filament winding and filament-wound pipes and tanks. Its typical viscosity of 200–400 cPs at 25 °C suits bath wet-out, and its typical gel time of 20–60+ minutes at 25 °C gives a long working window at the reference cure, MEKP 1.5% with cobalt octoate approximately 0.4%.
For the liner that faces the medium, the catalogue’s SPR 301 OS is listed for sewage pipes and solvent service, and Vinyl Ester Resin for more corrosive service.
Published typical values
| Property | Filament Winding Grade Resin (SPR 301 FW) | Organic Solvent-Resistant Grade Resin (SPR 301 OS) | Vinyl Ester Resin (SPR 501 VE) |
|---|---|---|---|
| Chemistry | Isophthalic unsaturated polyester | Isophthalic unsaturated polyester | Bisphenol-A Epoxy Vinyl Ester |
| Viscosity (typical) | 200–400 cPs at 25 °C | 200–400 cPs at 25 °C | 350 cPs (at 25°C) |
| Gel time / pot life (typical) | 20–60+ minutes at 25 °C | 15–35 minutes at 25 °C | 15–20 minutes at 25°C (see TDS test condition) |
| Styrene content (typical) | 35–45% by weight | 35–50% by weight | 40% |
| Reference cure | MEKP 1.5% + Cobalt Octoate approximately 0.4% — added separately during use | MEKP 1.5% + Cobalt Octoate 0.4% — added separately during use | MEKP at 1.5% — the dosage the published gel time is measured at |
| Source of values | 2026 catalogue; grade TDS | 2026 catalogue; grade TDS | Vinyl Ester Resin TDS |
Typical values, reproduced from each product’s own published data. They describe the liquid resin at its reference condition, not a finished part, and are not guaranteed limits.
Liner and structural wall
Many wound products are built with an inner liner — a resin-rich layer, often with veil and chopped strand — laid up or sprayed onto the mandrel before winding begins. The liner resists the medium; the wound wall resists pressure and loads. Using a more resistant resin in the liner and a winding grade in the structure is a common, deliberate design choice, not a compromise.
Limits and trials
No cured mechanical, pressure or chemical data are published for SPR 301 FW. Pipe stiffness, pressure class and joint performance are properties of the finished, tested pipe. On the line, bath life depends on bath temperature, volume and turnover; establish the practical working window with a trial wind of a full-length part.