Flexible Pipe Systems Configurations for the Pre-Salt Area

Unbonded flexible pipes are being considered as an actual solution for the following developments for the Brazilian Pre-Salt area. This technology is already being successfully used in the first EWT installed in the Brazilian Pre-salt and being qualified for the first Pre-salt Pilot Project development. However, unlikely the current project developments in water depths around 1500m, the free catenary configuration is not always an applicable option not only due to the 2500m water depth but also to the presence of contaminants such as CO₂ and H₂S in the conveyed fluids which in certain applications make the use of conventional high strength steels unfeasible, making the use of sour service armour wires mandatory. This paper presents the result of the global and local analysis performed for different applications such as 4^″ gas lift, 6^″ water injection, 6^″ production and 9.13^″ Gas export structures designed specifically for the ultra deep water in Brazilian Pre-Salt area. The aim of this study was to verify the feasibility of the free hanging catenary configuration and determine the most suitable flexible pipe system configuration for different applications, confirming that the flexible pipes are an adequate solution for the Pre-Salt even when the service life requirements exceeds 20 years and associated safety factors.