The process consists in winding up resin-soaked fibers (glass or carbon fibers…) on a mandrel, and then in polymerizing the structure (heat-induced polymerization in a sterilizer). The winding machines are digitally controlled and guarantee a perfect reproductibility of the fabrications. As a result, what we get are materials with very good mechanical characteristics (high fiber rate : 60 to 75 % by mass) and with the possibility to place the fibers optimally in the direction of the stress to support.

There are 2 kinds of winding, which can be combined during the tube’s fabrication process :

• Hoop Winding : (90-to-85-degree angle in relation to the mandrel’s axis) (”parallel winding”)
• Helical Winding : (80-to-30-degree angle in relation to the mandrel’s axis) (”crossed winding”)

Playing with the number of ”hoop” and ”helix” in the structure of a tube as well as with the given ”crossed” angle, it is possible to optimize the structure according to the stress supported by the part. After polymerization, the finished part is separated from the mandrel during the ”demandrelling” operation.

Here are the different qualities according to the nature of the parts :

• Carbon tubes : low density, good specific mechanical characteristics. High continuous use temperature (130°C).
• Hybrid tubes : glass/carbon combination (delamination properties under impact – shielding). These solutions make it possible to combine technical nature and design. Advanced material.
• Glass tubes (E-Glass fiber) : Glass-fiber tubes are used for applications requiring insulating tubes, which are able to resist internal pressures and high-temperature working environments (130°C max).