Van Gogh Project – Western Australia
Dynamic and Static Subsea Production Umbilicals
The Van Gogh development is part of the greater Vincent Field located 53 km north-northwest from Exmouth on the Western Australian coast. The Van Gogh oil field involves the installation of subsea well production equipment and connection to a Floating Production Storage and Offloading (FPSO) vessel. JDR was contracted to provide subsea production umbilicals for use at 350m water depth over a 20 year operating cycle.
The main JDR-designed umbilical, connecting the FPSO to the Drill Centre One manifold, is 4.17km. The infield umbilical to Drill Centre Two is 1.85km. The main umbilical riser was installed in a lazy-S configuration using distributed buoyancy modules. Internal ballast was incorporated into the dynamic section to ensure a correct dynamic response in the riser. All electrical cable quads included special low permeation outer jackets to mitigate the impact of hydrogen gas.
The FPSO incorporated a Disconnectable Turret Mooring Buoy (DTMB). The DTMB allows the vessel to disconnect from the field hardware in adverse weather conditions for relocation to safer waters, reconnecting when the storm has passed.
The umbilical riser was installed in the DTMB using a bull nose umbilical termination unit (BUTU) and bend stiffener latch mechanism (BSLM). The BSLM provided automatic connection of the dynamic bend stiffener and can be disconnected by an ROV (remotely operated vehicle) if required.
A Subsea Distribution Unit (SDU) was fitted to the main umbilical. Subsea Umbilical Termination Assemblies (SUTA) were fitted to both ends of the infield umbilical. The two umbilicals were delivered by JDR on standard 9.2m x 5.0m installation drums with the SDU and SUTAs attached for offshore installation.