Analysis and Repair of Delaminated Continuous Helical Ply in a Composite Pressure Vessel

The pressure vessels are designed with carbon/epoxy composite materials for better efficiency and ease of fabrication methods. Filament winding using helical, hoop and fabric layers is the major technology used for manufacturing of pressure vessel. The vessel is subjected to non-destructive examination after manufacture and defect study is done. Delamination in the composite plies is identified, mapped and analysed through finite element software. The delaminated zone in the component is identified and the corresponding helical, hoop layers are removed. Scheme for filling of composite angle plies is designed and the patches are repaired with carbon/epoxy composite. Further filling and joining plies are laid and the vessel is cured. Hydropressure test was conducted and the strains, displacements were recorded. The data are compared with the defect free vessel and a good correlation is achieved with ply-repaired composite vessel.