Long before the industry dared to dream that operating in the ultra-deepwater of the U.S. Gulf of Mexico could be possible, Noble took a bold and pioneering step in that direction. Believing that the deepwater was the future, the Company undertook the conversion of several shallow water submersibles into semisubmersibles known as the “EVAs.” The EVAs, which stood for “economic value advantage” leveraged Noble’s considerable engineering expertise and well-deserved reputation for efficient and safe operations.
The EVA rigs immediately demonstrated why they were so named. Several set water depth records. If there was any skepticism in the offshore drilling industry that a converted submersible could begin a new life capable of drilling in 7,000-8,000 ft of water, it was quickly swept away. One of the forward-thinking oil companies that contracted an EVA semisubmersible early on was Shell, beginning a15-year (and counting) partnership of continued innovation in the industry.
More recently, Shell contracted another one of Noble’s new ultra-deepwater semisubmersibles, the Noble Clyde Boudreaux, to batch drill 23 wells in water depths ranging from 7,800-9,000 ft of water for its innovative ultra-deepwater Perdido development project.
The Noble Clyde Boudreaux began life as a Russian-built hull that Noble had purchased. The hull was completely stripped of all of its original drilling equipment, offering Noble and Shell a clean slate that eventually became one of the largest and most technologically advanced drilling rigs in the Gulf of Mexico.
The Noble Clyde Boudreaux batch drilled 23 wells for Shell’s Perdido development project while moored in water depths up to 9,000 ft.
The rig was outfitted with the latest automated drilling and pipe handling equipment designed to take rig workers out of harm’s way and to increase performance while saving time. This upgrade included an automated pipe racking system and two iron roughnecks.
Upgraded mooring system
The Noble Clyde Boudreaux originally was designed to have a standard 8-point mooring system but after Hurricanes Katrina and Rita devastated the Gulf drilling industry with Category 5 winds, Noble conducted studies to make the rig capable of withstanding a 100 year storm.
“With participation from Shell, we redesigned the mooring system to a 16-point system based on the results of the studies,” said Dave Petitjean, Noble’s Project Manager during the rig’s upgrade. “We also redesigned it to be a larger and more robust system.”
The mooring wire was increased to 3 3⁄4-in. diameter from 3 1⁄8-in. diameter for greater breaking strength. Likewise, the chain was increased to 3 1⁄4-in. from 2 3⁄4-in. Finally, the size and weight of the anchors were upgraded to 18 metric tons from 12 metric tons. Shell employed a suction pile system for the Perdido wells so the larger anchors were not used during the project.
In order to accommodate the extra weight of the larger chain and wire rope and the 16 mooring winches, the rig was made more buoyant by the addition of smaller columns to each of the four corner columns and “blisters” to each pontoon.
While the Noble Clyde Boudreaux was drilling the Perdido wells, it received the U.S. Minerals Management Service’s (MMS) Lake Jackson District SAFE (Safety Award for Excellence) Award for 2007 and 2009. The rig was delivered in June 2007, and during the first year of working for Shell on Perdido, the rig completed the year with 1,086 days without a recordable or lost-time incident. The rig was visited and inspected nine times by the MMS during its first year of operations, with no non-compliance issues reported.
Noble Corporation’s innovation and commitment to safety has helped Shell to successfully complete the Perdido project, itself an innovative endeavor. These attributes have helped to build Noble into one of the world’s largest offshore drilling contractors capable of handling the most complex projects around the world with extra value added.
Noble Drilling Services Inc.
13135 South Dairy Ashford, Suite 800
Sugar Land, TX 77478
Tel: 1-281-276-6100 • Fax: 1-281-491-2092