Method for winding continuous fibre rovings for the manufacture of complex fibre-reinforced plastic components

Coreless winding for the production of complex three-dimensional support structures

Coreless filament winding is a continuous process for the production of continuous fibre reinforced composite components. By using this method, corrosion-resistant structural components with high mass-specific mechanical characteristic values and a high degree of geometric design freedom can be produced cost-effectively.

While complex three-dimensional load-bearing structures can be created quite easily in coreless winding, the individual elements have high deviations in their cross-sectional shape. This complicates the calculability of the structures and causes relatively large safety factors.

Scientists at the University of Stuttgart and the German Institutes of Textile and Fibre Research Denkendorf have developed a process for the production of coreless wound complex structural components with adjustable cross-sections. Using glass fibre rovings, the process according to the invention combines the great design freedom of the winding process with the high dimensional accuracy of pultrusion profiles. To produce the component, the fibre strand is continuously wound along spatially arranged deflection points (sleeves, pins, ...) freely in space. During the winding process, the fibre strand is only cured between the deflection points; the fibre strand remains flexible at the deflection points. This immediate curing by using UV radiation ensures the shaping of the fibre strand, which thus does not have to be cut to length and allows an integral construction. The process enables the production of resilient components with complex component geometries with adjustable and constant fibre strand cross-sections and fibre volume contents.

• Great freedom in component design
• Constant fibre strand cross-section
• Adjustable cross-section shape
• Reduced safety factors
• Smooth component surface
• High automation capability
• Adjustable fibre volume content
• No dripping of resin during production

Possible applications are structural components which currently consist of two or more parts (bolted or welded) and which can be manufactured in one piece using the process according to the invention. Possible applications are, for example, bicycle frames, brackets for exterior mirrors, satellite systems, rear spoilers or any kind of reinforcing struts.