BMT Scientific Marine Services Inc. has chosen Sonardyne International Ltd to supply an integrated acoustic positioning and telemetry system for Petrobras America’s Gulf of Mexico Cascade Chinook field.

The system forms part of an extensive life-of-field integrity monitoring system for five Free Standing Hybrid Risers (FSHRs).

The Cascade Chinook field development is the first use of an FPSO (Floating Production Storage and Offloading) system in the Gulf of Mexico. All risers, umbilicals and monitoring system transceivers are integrated into a turret buoy which can be disconnected from the FPSO allowing it to move off-station when there is a threat to the facility.

The selection follows the successful development and deployment by BMT and Sonardyne of a similar system for a deep water field in Brazil.

The acoustic instrumentation is configured to monitor the position of each riser tower and the turret buoy in relation to the seabed. Integrated sensors will also monitor depth, temperature, inclination and sound speed. The integrated modem or telemetry functionality will also transfer the data from BMT’s load and attitude monitoring system on each riser tower to the turret buoy at the central location.

The turret buoy is fitted with a number of transceivers to ensure a line of sight to each riser tower without obstruction by the risers or mooring lines. These transceivers are controlled by BMT’s monitoring system in the FPSO’s turret to acquire position, sensor and load monitoring data. In the event of a disconnection the system continues to record data which can later be downloaded by the FPSO or another vessel. The system uses Sonardyne Wideband® signal architecture that enables remote high speed and reliable data communications through water.

The integrity monitoring system will provide valuable data about the movement and loading on hybrid riser systems during extreme weather. The system demonstrates a growing demand for reliable subsea remote integrity monitoring that has been enabled by the high performance of Sonardyne’s Wideband® acoustic positioning and data communication systems and BMT’s proven subsea strain and motion sensing systems.