Testing composite riser

August 8, 2001, 10:15 CEST

Statoil is currently testing a riser made from a light composite on the Heidrun field in the Norwegian Sea. The riser has been specially developed for drilling and production in deep waters.

Never before has a composite riser been tested on live production wells, and the results are promising, reports project manager Gisle Stjern.

He says that Statoil can see major benefits in the equipment, since more and more of the group’s operations are taking place in deep waters.

The riser being tested, CompRiser, is composed of carbon fibre and epoxy resin. A composite riser weighs half that of an equivalent steel riser, and the gain lies mainly in the material’s low specific gravity, says Mr Stjern: “A drilling rig that can operate in water depths up to 400 metres with a steel riser will be able to go down to 800 metres with the new riser.”

He adds that the supporting structure of new floating rigs can be made lighter than before through the use of composite risers. Furthermore, this material opens up the possibility of developing deepwater fields that until now have been impossible to develop due to the weight of the drilling and production equipment.

The CompRiser has been developed by Kværner and Conoco, with financial support from Statoil.