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Advanced Composite Materials

* Composite materials offer several advantages for marine construction

because of their low density, corrosion resistance, high thermal

insulation, high structural damping and excellent fatigue performance.

In addition, the use of composites allows for greater design flexibility by

tailoring the properties to meet specific design requirements, thus promoting

better system-oriented solutions. On a one-to-one replacement basis,

composite components are often more expensive than their steel counterpart.

However, on a performance equated basis, the economic incentive to use

composite components can often be demonstrated based on their capability

to reduce system and life cycle costs.

* Fibreglass composites, and to a lesser extent carbon composites, have

been used by the offshore oil industry in a variety of applications. Some

specific examples for the offshore application of fibreglass composites

include firewater piping, seawater piping, storage vessels, grating, fire

and blast walls, cable trays, mud mats and subsea wellhead.

* Almost all Tension Leg Platforms (TLPs) in the Gulf of Mexico have used

fibreglass pipe for the firewater ring main and gratings. While in the past

many operators had very disappointing experiences with leaks of fibreglass

pipe joints, recent applications of fibreglass pipes on several offshore

facilities have shown that the leak rate of several thousands of field joints

was less than 0.1%. Composites have also been used for many high-pressure

vessel applications. These vessels are manufactured from glass and carbon

fibre composites with a thermoplastic liner.

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