When done right, high-performance composites enable outstanding lightweight designs for structural components and open up further advantages such as very good damping properties or high corrosion resistance. More than ever, current and future series applications must be developed, manufactured and put into service economically in order to be able to compete with metallic lightweight designs. A key element is the joining technology, which might influence the mass and cost balance in a negative sense due to potentially necessary laminate doubling and processing or quality assurance steps.

In this context, the team of LZS GmbH has developed and tested a new type of connection for composite profiles subjected to tensile and compressive loads. It is based on a formfit supported pressfit connection in circular cylindrical composite hollow sections (see Fig. 1). This enables the use of cost-effective composite tubes while at the same time being much more robust than pure structural bonds. All in all, components such as hydraulic cylinders (see Fig. 2), piston rods and generally tension and compression struts can be manufactured much more cost-effectively than with other known formfit load transmission systems such as bolts or loops.

Because of the clearly defined joining parameters, the Helix-PressFit connection can be included in a design and dimensioning guideline, significantly accelerating future development and design processes. We as the LZS team have driven this exciting connection up to experimental „proof of concept“ and are looking forward to interested users to bring this system on the road, in the air, in space, in water or simply into their machine shop!