Manufacture and Bending Test of a Cylindrical Laminated Tube with Integrally Formed Ring Flanges

The connection problem of composite tubular members in the domain of transmission ducts and assembly structures remains an obstacle to the wide application of continuous fibre-reinforced composites. Traditional longitudinal connection techniques of composite tubular members to address this problem mostly require the use of metal connectors, which reduces the weight reduction effect of composite materials to a certain extent. To explore a new solution, a cylindrical laminated tube component with integrally formed ring flanges is proposed in this paper with a detailed design. The component was fabricated using a prepreg hand layup and compression moulding process, and was then tested under cantilever bending conditions to obtain the bending performance of the bolted composite flange connection. The results suggest that the continuous fibre placement scheme from the tube part to the flange adopted in the design could ensure a good integrity of the component, but also cause nonuniform laminate properties in the flange. A theoretical model constructed for the evaluation of the flange laminate properties is used for the modification of a subsequently established finite element model. The effectiveness of the fabrication method is verified by comparing the finite element results with the experimental results. Compared with a conventional steel-FRP joint, the proposed component can be used for the fast longitudinal assembly of laminated composite tubes with an all-composite bolted flange joint to bear loads and save the need for a traditional indispensable metal connector.