Composite riser repair standards

This chapter will first outline the conventional offshore riser repair techniques and their limitations which, in turn, provide the motivation for adoption of composite repair. A brief discussion about the application of FRPC in pipeline repair, its limitations, current practices, and material types will be given. A subsequent section provides information on the industrial design and safety standards used in designing and assessing the performance of offshore risers, corroded pipelines, and pipelines repaired with FRPC. The typical loading conditions of an offshore riser are also discussed so that the requirements of CRS can be understood. 

Before conducting a repair on a corroded pipe, analysis must be done to determine whether a repair is sufficient to restore the strength of the riser. This can be evaluated using the codes provided in ASME B31G (1991). The standard used here is compliant for onshore pipelines where the equations are only functions of the corrosion dimensions and internal pressure. Nevertheless, it provides a basis for determining the required thickness of the composite laminate. 

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