The continuous filament winding process is used to manufacture composite materials. It involves continuously winding reinforcing filaments (such as fiberglass, basalt fiber, or other materials) onto a rotating mandrel while simultaneously impregnating them with a polymer resin. This technique is particularly suited for producing high-strength, lightweight, and cylindrical composite structures like pipes and tanks walls.

The manufacturing of continuous pipe is carried out on a mandrel assembled with discs, aluminum beams and steel band, sized according to the pipe diameter required.

The steel band moves in the axial direction, sliding over the ball bearings inserted in aluminum beam grooves. At the end of the mandrel, an exit head guides the steel band back into the mandrel inner pipe, which supports the exit head. On the opposite end of the mandrel near the cam plate, the steel band is wound on the mandrel again, forming a smooth surface with simultaneous rotation and advancing in the axial direction. The glass fiber laminate is applied onto the moving mandrel according to the following procedure: firstly, a release film, e.g. polyester film, is wound on the mandrel, followed by a surface veil (“C” glass or synthetic), both of them supported by proper winders. Glass roving, together with chopped glass, sand aggregate and polyester resin, is applied simultaneously in the correct position, according to design specifications. Finally, a layer of surfacing veil is applied.

The resin feeding on the continuous winding machine consists in feeding the resin and catalyst from respective resin daily mixers and the catalyst storage tank by dedicated pumps and via separate piping to the continuous winding machine dozing station. The resin and catalyst mixing are pumped on the winding machine shortly before feeding the mix on to the pipe/coupling under production. The mixing operation is carried out with static mixers.

After the pipe has cured, it is automatically cut and calibrated on-line and the pipe length is selected by the operator between min. 3.100 mm and max. 12.000 mm. Other pipe lengths based on customer requirement are possible, but subject to prior techncial analysis.