Filament-wound pressure vessel with thick metal liner

A method for calculating stress and strain in non-symmetric filament-wound pressure vessels with thick metal liners, up to burst pressure, is presented. The calculations are based on classical laminate theory and Tsai-Wu failure criterion. Plastic yielding of the liner and transverse cracking of the composite are not considered failures of the vessel and are modelled by reduced properties. The effect of changing thicknesses of various layers, on burst pressure and efficiency of the vessel, is considered. It is shown that the efficiency of a thick liner reinforced with filament winding can approach optimal values that are quoted in the literature, even when the liner is selected arbitrarily. The calculations agree with test results of two 6 litre vessels having the same liner: one with Kevlar 49/Epoxy overwrap and the other with T300 Carbon/Epoxy.