Influence of the filament winding tension on physical and mechanical properties of reinforced composites

Abstract In this experimental investigation the influence of the applied tow tension during filament winding on the physical and mechanical properties of glass-fibre reinforced polymeric composite tubulars, was studied. Pressure retaining tubular products used in the transportation/storage of fluids are generally subjected to a variety of loading conditions during their service life; thus tubular specimens were tested under different biaxial loading ratios. The stress/strain response was recorded and functional and structural failure envelopes were developed. These envelopes indicate the leakage and final failure characteristics of the components, respectively. The mechanical properties were analysed in conjunction with the measured physical properties: ‘fibre volume fraction’ and ‘effective wall thickness’. Experimental findings demonstrate that the component strength depends on the degree of fibre tensioning. Under fibre-dominated loading conditions, higher winding tension leads to an improved resistance against failure of tubular components, whereas under matrix-dominated loading failure is delayed by reduced fibre tensioning.