Delmar Systems, Inc. and Shell Exploration and Production Co. established a new world-record depth for moored vessels using suction anchor technology in the Gulf of Mexico.
The Transocean 5th generation semi-submersible rig, Deepwater Nautilus, was moored in 8,951 feet of water in Lloyd Ridge Block 399 (Cheyenne) with the deepest anchor at 9,205 feet. This ultra-deepwater mooring project was accomplished using high-strength synthetic mooring rope connected to suction anchors. This achievement surpasses the previous world record water depth record of 8,717 feet set last year by Shell in Alaminos Canyon Block 857.
The world-record installation was accomplished in a two-step process whereby the suction anchors were pre-installed using only one anhcor-handling vessel, the Laney Chouest, which is owned by Edison Chouest Offshore, Inc. The eight mooring legs were then connected to the rig at a later date using lighter weight polyester rope and the patented Delmar Subsea Connector, allowing for quick connection once the rig arrived on location. The reduced weight of the polyester rope increases the rig’s variable deck load, permitting the rig to anchor in deeper waters.
The ability to moor conventional semis in these waters and beyond has been non-existent until this technology was developed, tested, and utilized. To date, Delmar has deployed and recovered more than 400 suction anchors for multiple MODU operations—more than any other contractor. This method and new lighter weight technology will play a major role in achieving the industry’s deepwater goals as the quest for oil and gas exploration continues into deeper waters.