Brian Spencer, president of Spencer Composites Corp. (Sacramento, Calif.), focused on real and potential use of carbon fiber in offshore oil and gas applications. Use of composites in offshore oil and gas has been talked about for years, and the potential in this market is substantial. Spencer noted, however, that the oil exploration industry offers several challenges: Conservatism and familiarity with metal, high exploration and development cost/risk, harsh environment, in-service inspection requirements, and increased distance from existing infrastructure.
Incentives for using composites, however, are sustantial: Light weight, corrosion resistance, fatigue resistance, embedded instrumentation, thermal insulation, increased damping. Potential carbon fiber use in exploration structures includes: 45 to 50 lb/ft in drilling risers; 10 to 12 lb/ft in production risers; 6 to 7 lb/ft in choke and kill lines; 2 to 5 lb/ft in auliliary lines; and 16 to 17 lb/ft in 270-mm-diameter tethers. One tension leg platform (TLP), said Spencer, with maximized use of carbon fiber, could use more than 7 million lb/3.18 million kg of the material.
Spencer also evaluated carbon fiber use in pressure vessels and flywheels, the latter of which is being developed for storage of wind energy during non-peak generation. One fly wheel, he said, could consume as much as 1,100 lb/500 kg of carbon fiber.
Noted accomplishments of carbon fiber in exploration and storage include: A composite drilling riser in the Heidrun oil field (North Sea) has been in service since 2001; a U.S. Department of Energy-sponsored project for deepwater composite drilling riser is under way; a composite auxiliary line project is under way; frequency regulation using a composite flywheel is certified.