Axial mechanical experiments of unbonded flexible pipes

Probabilistic failure analysis of underground flexible pipes

Methods for estimating structural reliability using probability ideas are well established. When the residual ultimate strength of a buried pipeline is exceeded the limit, breakage becomes imminent and the overall reliability of the pipe distribution network is reduced. This paper is concerned with estimating structural failure of underground flexible pipes due to corrosion induced excessive de...

Sealing Performance of the End Fitting of a Marine Unbonded Flexible Pipe under Pressure Penetration

The sealing performance of end fittings is very important for offshore oil and gas pipelines. To investigate the sealing behavior of a ring-shaped wedge seal, global and local numerical models of the ring–pipe interaction have been developed based on the finite-element method. First, the sealing process of the ring under pressure is simulated. Second, a criterion for the penetration of fluid pr...

Experiments on vertical slender flexible cylinders clamped at both ends and subjected to axial flow.

Three series of experiments were conducted on vertical clamped-clamped cylinders in order to observe experimentally the dynamical behaviour of the system, and the results are compared with theoretical predictions. In the first series of experiments, the downstream end of the clamped-clamped cylinder was free to slide axially, while in the second, the downstream end was fixed; the influence of e...

Effect Of Electric Field On Liquid Viscosity in Co-Axial Cylindric Pipes

A Segmentation Technique for Flexible Pipes in Deep Underwater Environments

This paper presents a novel segmentation technique for flexible pipes in deep underwater environments. It consists in finding regions of the pipe denominated vertebrae and has three stages. Firstly, the input image is pre-processed to reduce noise. Secondly, the pre-processed image is binarized by the proposed Multi-level Topological Binarization technique, resulting in an image which highlight...