Catenary Risers
The heaviest components which connect the platform to the well head are the steel catenary risers, used to inject water, export gas and bring production oil to the surface for offloading. Since these risers hang freely from the platform, there is much impetus towards reducing their weight, a process which can substantially affect the platform's size and cost, and help access deeper water reservoirs. Of course, this must not be at the expense of the riser structural integrity and instrumentation of the SCR sections is now desirable in order to ascertain the performance and lifetime structural integrity of the riser systems, particularly at the top sections and seabed touchdown zones where fatigue damage is most likely. fiber Bragg grating strain and temperature sensor arrays offer a perfect solution to this instrumentation challenge, due to their high multiplexing capability, zero power, remote deployment, and long-term stability.

Composite Risers
As accessible fossil fuel resources become less plentiful, the requirement to access reservoirs in deeper water is becoming increasingly important, and the technical difficulties associates with relatively heavy riser systems are becoming limiting. To meet this challenge, a consortium of offshore companies have been involved in a project for several years to develop composite risers for such deepwater applications.

Since 2000 we have been assisting this project, and our involvement has introduced embedded fiber sensors to create a "Smart" pipe whose structural integrity can be continuously monitored. More details are given in our project pages.

FPSO Umbilicals and Anchor Cables
The umbilical connections between FPSOs and the well head, and the anchor cables which attach these to the piles sunk into the sea bed, are another potential application of Smart Fiber technology. These large flexible connectors, either cables or continuous tubes, are a vital part of the rig attachment and must therefore be produced to withstand the most testing conditions. In the same way as the catenary risers, the umbilicals could be effectively monitored by the inclusion of armoured fiber optics and sensor arrays.

Sea-Bed Pipelines
A rapidly expanding area of composite use is the replacement of conventional steel pipes by composite filament wound tubes. The composite pipelines, although advantageous from a production, weight and cost point of view, are subject to significant stresses imposed by ocean currents and the pressure at depth. The monitoring of the structural health of the pipeline, especially for signs of weakness and corrosion, would help to prevent problems such as salt water contamination of the contents.