Submerged floating pipeline in deep water

Installation of conventional pipelines in areas with very irregular seabed bathygraphy may require large amounts of intervention work, e.g. gravel dumping or dredging. To facilitate pipeline installation in those areas with a minimum of intervention work, a Submerged Floating Pipeline (SFP) could be installed. The concept consists of a floating pipeline, which is anchored to the seabed by inclined or vertical tethers in an off-bottom configuration. The SFP concept is a novel technology and represents an interesting potential for relevant applications. At present, the concept is being developed and evaluated as an alternative for the gas export pipeline system from the Ormen Lange Field located outside Mid-Norway. This paper presents some key features and design aspects that are relevant for the SFP concept. The analyses are carried out based on a 20-inch internal diameter pipeline installed in 1000 m water depth.