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components contained within the vessel’s hull.

These components are:

1. The chain-table, including chainstoppers,

2. The turret cylinder,

3. The friction pad assemblies and support structure,

4. The main weathervaning bearing and its support structure,

5. The turret moonpool structure.

These components are described in more detail as follows:

The chain-table forms the connection point for the anchor lines of the turret

mooring system to the FPSO vessel. Mooring loads are transferred from the

chainhawse connection points through the chain-table structure to the turret

cylinder, and via the vessel friction pads and main weathervaning bearing into the

ship’s structure. The chain-table also provides the entry points for the product
risers and houses the foundations for the bend restrictors (as required).

The chain-table deck, which is approximately 1.5 meters deep is formed of
welded steel plates. The deck consists of an external support ring box for the

chainstoppers and a clear central opening which allows the entry of the risers and
free passage of water flow in and out of the turret.

Chainstoppevs and Chainhawses

Nine (9) chain hawse supports, each consisting of two cast steel pieces

having a hook shape, are welded to the chain-table deck. The chain hawse

assemblies complete with automatic chainstoppers are fitted into the hooks via a

self lubricated bearing which allows the chain hawse to rotate and align with the

chains. A tubular guide trumpet ensures proper alignment of the chain during

tensioning and helps the articulation of the chainhawses.

This system allows the chain to be hauled in when the mooring line is

pulled, and to be locked as soon as the tension is released. The chain hawse and the

automatic chain stoppers are of a design, which has successfully used on previous

projects and reduces the time to hook-up the FPSO vessel to the preinstalled
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