Floating catenary riser system concept for brownfield application

The expansion of a deepwater brownfield may become necessary to increase the production of hydrocarbons. Such expansion often requires the installation of additional risers to the existing floating production platform. However, the seabed footprint of the existing facilities may be congested with existing subsea pipelines and structures. Tying back of risers such as steel catenary riser (SCR) to the floating platform becomes challenging. Floating catenary riser (FCR) is a novel riser solution with floating bends or 'waves' close to the seabed. The FCR is engineered to extend its touch down point (TDP) far beyond the nominal TDP of the SCR and away from the congested seabed footprint. The riser sections before the nominal SCR TDP is configured to float by installing buoyancy modules. The multiple wave buoyant sections also provide the FCR with the capability to decouple its touch down zone (TDZ) from the floating platform motion. This can result in a significant reduction in the stress and fatigue damage around the riser TDP. Presented in this paper are the FCR configuration development and global responses to vessel offsets, current drag load impact, combined load, and wave fatigue loads, simulated to demonstrate the FCR feasibility.