Optimizing Additional Stabilization Requirements of an Existing Pipeline

Abstract

In order to increase oil production, an oil field operator undertook a field expansion program which required the construction of additional satellite platforms and several new artificial islands as centres for future drilling and oil production facilities. As a result of these newly constructed islands, wave and current conditions within the surrounds became more severe. Some sections of the existing pipelines in the vicinity of the new artificial islands were identified to no longer satisfy DNV-RP-F109 Generalized Method's stability criterion of pipe lateral displacement for less than ten (10) times the diameter. This resulted in the need to employ additional stabilization measures for these affected sections. As a consequence of the high costs associated with these measures and the inherent conservatism in the use of small allowable displacements as a failure criterion, a dynamic analysis using finite element method was used to assess the pipeline displacement and the structural integrity responses during a storm duration. This paper details the use of such dynamic analysis to optimize the additional stabilization requirements for one of the pipelines in the field. The results demonstrate that significant cost savings for the operator could be achieved using this method.