The Latest Developments In the Design And Simulation of Deepwater Subsea Oil And Gas Pipelines Using FEA

This paper gives an overview of the latest developments in how advanced finite element analysis (FEA) tools can be used for the design and simulation of subsea pipelines and components. Through the use of these tools, it allows designs to be undertaken for complex scenarios that were not previously possible, and confronts key technical design challenges such as pipe-in-pipe (PIP) in deepwater and high-temperature situations. This paper is split into three main parts, and covers the use of cutting-edge FEA tools for the design and simulation of pipelines and components. The first part looks at the ‘global’ analysis of pipelines using a highly non-linear finite element (FE) program, which has been developed called 'Simulator, and uses ABAQUS as the finite element engine. These tools can be used to undertake complex design cases such as lateral buckling, upheaval buckling, reeling and installation analysis, single pipe and pipe-in-pipe response, pipe-soil interaction, fatigue, expansion-span analysis and thermal buckle management. The second part of the paper demonstrates how FEA can be used to undertake ‘local’ modeling of pipelines and components. A local full-size PIP FE model is used to verify the global PIP FE model at a local level. Also solid modeling of complex subsea components such as bulkheads, flanges, girth welds and clamps are described. The third part of the paper looks at an integrated approach to route selection, using three-dimensional (3D) software and stress analysis, to reduce pipeline length and minimize intervention. Using the above-mentioned tools, project examples are then given where the FEA tools are used to address deepwater and high-temperature issues. The combination of these analysis tools allows solving some of the most complex engineering problems presently faced in the industry, and in some cases has allowed significant cost savings to be achieved in the engineering.