Some internal mechanical aspects of flexible pipes, cables and umbilicals for marine applications

Much research work has been carried out on the dynamics of flexible tubulars for marine applications, principally to ensure the avoidance of unacceptable excursions in bend radius or in tension. Comparatively little attention has been paid to the consequences of global loadings on the stresses and strains in the individual components of these and other flexible elements. This paper reviews the state of knowledge of such internal mechanical effects and focuses on two examples recently studied by the authors. The consequences of these in static and (more particularly) dynamic failure prediction are also discussed. Such an approach is necessarily highly product-specific but every attempt has been made to preserve a methodological approach so that application can be made to a range of products for different uses. The general approach is analytical rather than numerical so that the use of (for example) finite element packages has been minimised in the interests of simplicity and versatility of application. © 1992.