Installation and Decommissioning

Definition

Pipeline installation is a highly nonlinear 3D process (Trapper 2019), which involves coupled in-plane and out-of-plane phenomena, such as full pipeline-seabed interaction, lateral buckling, lateral stability under hydrodynamic loads, torsion, sideway walking, etc. If the laying of pipelines is finished prior to the arrival of the platform or encounters bad weathers, the pipelines need to be abandoned onto the seabed, and recovery and reinstallation of pipelines need to be carried out when the platform is available. In the abandonment operation, the A&R cable lowers a pipeline down to the seabed by a pull head and in the recovery operation lifts it up to the sea level (Wang et al. 2015).

Scientific Fundamentals

Installation of Risers and Pipelines

With the discovery of offshore oil fields in the shallow waters of the Gulf of Mexico during the late 1940s, offshore pipeline installation was invented. The first “offshore” pipeline in the Gulf of Mexico was constructed in 1954....