History

Tri-Catenary mooring systems (TCMS) were first designed for extended well testing (EWT) in the North Sea in the mid 1990s. They provided a better and more cost-effective alternative to dynamic-positioning tankers.

After various EWT projects, the TCMS system was successfully used to moor storage tankers and floating production, storage and offtake (FPSO) vessels. It provided an alternative to submerged turret production buoys, tower yoke mooring systems and conventional multi-line turrets for vessels up to 250,000 DWT, most notably for marginal fields where the field economics dictate a simpler, easy to deploy mooring system for fields with a limited production life.

Since first deployment in 1996, TCMS has been:

• Used on EWT, EDOR, FSO and FPSO applications
• Best known is Isis FPSO offshore Tunisia, 138,000Te DWT
• On station for 3.5 years with zero downtime
• Deployed on Oudna (2005), Didon (2007), Arthit (2009) and Westaf (2009)