Deepwater Production TTR Design

As the majority of “easy access” reservoirs have been discovered, deep water exploration and production is at the forefront of the Oil & Gas industry. Operators have utilized Top Tensioned Riser (TTR) systems in deepwater on Spar and TLP platforms and are now well established in the US Gulf of Mexico (GoM), West Africa and Asia. However, new reservoirs, particularly in the US Gulf, will be discovered in ultra-deep water (∼10,000 ft) with high pressure (HP) (>15 ksi) and high temperature (HT) (>284 °F). In such conditions, the criticality and complexity of a production TTR system is significantly increased. This paper addresses key design issues and considerations including wall thickness sizing, material selection, manufacturing capabilities, interface management and qualification testing.