Exxon Sculpin Ocean Monarch ultra-deepwater project

With hard bottom soil conditions and Exxon’s desire to use the mooring system on board the semisub Ocean Monarch as much as possible, Delmar Systems worked with Exxon’s technical group to design a mooring solution that would allow the rig to moor on a drag anchor/chain/wire system in just under 2,280 meters of water.

Exxon’s VIC/P70 block is located approximately 90 – 100 km off the East Gippsland Victorian coast, Australia, and includes the ultra-deepwater Sculpin-1 well.

Using detailed load sharing calculations, Delmar Systems provided the needed technical numbers to ensure a safe and efficient installation and recovery while sharing the mooring load between the boats and rig. In practice this came down by using a combination of the rig’s onboard chain/wire mooring system, over 1,000 meters of chain extensions (per leg), 2,000 meters of insert wire (per leg), and 110 kips of submersible buoyancy (per leg).

Buoys and insert wire were used to elevate the mooring line catenaries and keep them off of the MODU’s anchor bolsters with such a deepwater catenary mooring solution.