Composite repair of pipelines, considering the effect of live pressure-analytical and numerical models with respect to ISO/TS 24817 and ASME PCC-2

Wrapping composite material around the defected pipe is a recent method in pipeline rehabilitation. ISO-24817 and ASME PCC-2 are the only available design codes for the design of this repair system. For the case when the corroded pipe contributes to the load carrying capacity, the two codes suggest calculating the repair thickness for a special design pressure based on the pipe diameter, remaining wall thickness, pipe and composite material properties, composite allowable strain, and the live pressure, which is the internal pressure in the pipe at the time of repair application. In this study, a range of design scenarios are modelled using analytical equations and finite element method in order to assess the validity of including live pressure in the design. Results indicate that the repair thickness is independent of the live pressure and hence an appropriate modification is proposed to the existing design equation.