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times.

Fluid transfer from the seabed flowlines is achieved by flexible risers which

are suspended from, and routed through the turret mooring to the interface with

rigid piping at the manifold deck level. After manifolding the product is routed

through toroidal swivels to the vessel’s main deck piping and process facilities.

Lift gas is compressed on board the FPSO and transferred by a high-pressure

swivel to the gas lift riser. Inject water is pressurized on board and transferred by a

high-pressure water injection swivel to the water injection riser.

The turret’s manifold area is protected from possible wave action (green

water) by a wave breaker structure mounted on the vessel. A pedestal crane serves

the complete turret to handle swivels and perform other maintenance functions. A

stair tower is integrated with the crane superstructure to provide access to the

swivel stack area.
A hydraulic power unit provides power via the swivel to activate the

different valves in the manifold. Swivels are also provided for well control fluid
and signals. Electric power is provided via a distribution system serving an exterior

floodlighting and an interior accessway lighting of the complete turret.
The turret would be classified as the hazardous area, consisting of Zones 1

and 2. The turret cylinder would be monitored for the presence of gas. Fire and gas

detectors would be located in the manifold swivel area. All signals would be

transmitted to the FPSO’s central fire and gas control panel.

During inspection, temporary ventilation inside its annulus and cylinder

would be provided by air fans. The manifold area and the swivel stack are situated

above the vessel’s main deck and are thus freely (naturally) ventilated.

Fire protection inside the turret cylinder area is effected using portable fire

extinguishers, as the possibility of fire occurring in this area is considered remote.

Moorings Interface

The mooring forces applied to the vessel are introduced and accommodated

by the turret
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