Deep-sea mooring test successful

Nov. 15, 1999
A project sponsored by five major Gulf of Mexico operators has demonstrated a new ultradeepwater mooring system for mobile drilling units.

A project sponsored by five major Gulf of Mexico operators has demonstrated a new ultradeepwater mooring system for mobile drilling units.

Houston-based Aker Marine Contractors Inc. (AMC) and Marlow Ropes successfully completed testing of the new technology, which is part of a program sponsored by BP Amoco PLC, Chevron Corp., Mobil Corp., Vastar Resources Inc., and BHP Petroleum Pty. Ltd.

The new technology's components are expected to allow drilling units to be moored in water as deep as 10,000 ft. Both the US Minerals Management Service and the American Bureau of Shipping have approved the system.

As part of the testing of the new technology, AMC installed its suction-embedded plate anchor-handling construction vessel (SEPLA), the Cal Dive Aker Dove, as a preset mooring in 5,000 ft of water. The mooring components were load-tested to about 350 tons using the Aker Dove and the Seacor Vanguard, Seacor Marine's recently built anchor-handling vessel.

During the 1.5-hr test, and while using suction techniques activated from the Oceaneering Millennium ROV, the SEPLA reached full embedment of about 85 ft. The vessel then deployed the polyester rope.

As a stand-in for one of the conventional mooring legs, the mooring was linked to Diamond Offshore Drilling Inc.'s Ocean Victory semisubmersible drilling rig.

The mooring will be utilized for the duration of the drilling of one well, says Aker Marine. It will then be disconnected from the rig, recovered, and taken to shore for extensive inspection, loading testing, and analysis.