Deep And Ultra Deep Riser Concepts Allowing to Maximize Local Content

As hydrocarbon fields are discovered in ever deeper waters, a need for innovative riser concepts allowing putting into production such fields has arisen. In addition, current trends show that local content is becoming more and more important especially in West Africa and in Brazil. For these reasons SAIPEM has developed an evolution of the Single Independent Riser (SIR) in order to answer to both deep water and local content requirements. The Single Independent Riser is an innovative riser solution aiming at deep and ultra-deep water depth while featuring a significant ratio of local content. The SIR is based on a hybrid solution composed, from bottom-up, of a rigid part vertically tensioned by means of distributed or continuous buoyancy and a flexible jumper. This evolution is based on an innovative material that has been developed by SAIPEM: the Glass Bubble Gum. This material is composed of a gel and glass bubbles. The insulating gel makes it a highly efficient insulating and light material. The glass bubbles further decrease the density of the material making it significantly buoyant. This material features a slightly exothermic reaction and significant pot life allowing it to be poured in large quantities which make it fit for continuous buoyancy applications. The chemical components and properties of the GBG make it easy to fabricate in a local yard. An extensive qualification program is being completed. The SIR features improved dynamic behaviour of the rigid riser section under fatigue/extreme environmental conditions. The configuration of the flexible jumper ensures the displacements of the rigid riser section of SIR are significantly decreased compared to SHR. Using locally fabricated continuous floatability makes it possible to assemble the SIR onshore and install it using towing methods. Alternatively, the quad joints can be fabricated onshore and a conventional J-lay method can be used offshore. Both these solutions feature a high ratio of local content.