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anchorlines.

The bearings of the chain hawse shafts are formed of low friction material,

designed for full operational lifetime of the system, to allow rotation about a

horizontal axis, which is perpendicular to the chain. This articulation allows the

chain hawse assembly to pivot and thus minimise the interlink movements that are

experienced by the top of anchor chain, virtually eliminating wear and chafing.

Turret Cylinder

This structure is the principal support element of the deck’s turret section. It

is supported from the main roller bearing and constitutes a circular stiffened shell

member approximately five metres diameter, which extends from the chain-table

up through the total hull depth. At the main deck level, a circular penetration

allows the turret cylinder to continue until approximately four metres above the

vessel’s main deck, where it is supported by the main weathervaning bearing.
An annulus between the turret cylinder and the moonpool shell provides a

flooded passage for the anchor chain connection lines. The chains pass to
individual mooring line gypsy winches. The turret cylinder houses the riser and

umbilical ‘I-tubes’, which provide protection to the flexible risers over their transit
height inside the turret cylinder.

The turret cylinder extends from the chain-table up to the vessel’s main deck

and also supports the turret main deck, the manifold structure. the swivel stack and

all earth bound parts of the fluid transfer system.

Bearing Support Stvuctures

Weathervaning Bearing Support Structure - In order to effectively transit the

vertical and the horizontal mooring loads from the turret chain-table and the turret

cylinder into the FPSO vessel’s structure, and to keep deformations at the main

weathervaning bearing support within very tight tolerances, a conical piece of

welded structure is fitted. The continuation of this cone forms the outside shell of

the turret moonpool and interfaces with the vessel’s structure. On the one hand,

this conical structure must be flexible enough to decouple the bearing from the
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