Espirito Santo: Design and Operational Expereince of the Use of Steel Risers on a Turret-Moored FPSO

The centrally located FPSO facility is the Espirito Santo. The BC-10 joint venture charters the FPSO facility from SBM Offshore jointly with MISC under a long-term lease and operating contract. A unique feature of the BC-10 development is the use of steel lazy-wave risers (SLWRs) in conjunction with an internal turretmooring system. This is the first use of SLWRs in the industry, and the first time a steel-riser system of any configuration has been used with an internal turret-mooring system. After more than 5 years of operational experience, the integrity of the turret and riser system has been demonstrated in field conditions. The intent of this paper is to describe the impact of the use of SLWRs on the turretmooring system, and to report the in-service inspections carried out to verify the ongoing integrity of the riser system.