Rowan Cos. Inc., Houston, is currently designing the first of its new Tarzan-class jack up rigs, which was unveiled during a conference call in July 2001. Following the 9-12 month design period, construction will start on the Scooter Yeargain in 2002 at LeTourneau Inc. yard in Vicksburg, Miss., with rig release and deployment targeted for the third quarter 2004.
The Tarzan-class rig will be one-third the size of Rowan's Gorilla-class rigs, according to Bill Provine, vice-president for investor relations. The new rig will have one-third the steel and will cost about $70 million, depending on inflation and other unknowns, compared to about $200 million for a Gorilla-class rig.
Targeting the Gulf of Mexico shelf, the rigs will be capable of operating in 250 ft of water and drilling past 15,000 ft. The new rig class will have as much power as the Gorilla-class rigs, with three 3000-hp mud pumps, providing the hydraulic budget necessary to drill 15,000-ft TVD wells, extending a mile out laterally from the platforms.
Operators have identified Miocene sands under older fields on Gulf of Mexico's continental shelf, often under the salt. "The Tarzan-class rigs will be perfect for this application," said Provine. The Gorilla rigs can do the work but are too big and expensive for the Gulf of Mexico market.
The Gorillas-class rigs, having almost 1acre of deck space, were intended for deeper water and harsh environments like the North Sea with 50-ft seas and 100-mph winds. The Gulf of Mexico shallow water environment simply doesn't require that big of a structure.
Rowan has only one Tarzan-class rig slated for construction, says the company, and having just entered the design phase doesn't have to make the decision about additional rigs at this time. Since LeTourneau Inc. is entirely owned by Rowan, options for construction of additional rigs, as a package are not required.
Provine said it's an option for Rowan to sell off older assets as the Tarzan-class rigs are brought out of the construction yard. For example, Tarzan-class rigs could replace older rigs like Rowan's four LeTourneau 52-class that range 28-31 years old.
The new rig's namesake, Scooter Yeargain, is a 50-yr Rowan veteran and current LeTourneau Inc. chairman.
In other news, Rowan expects to complete construction on Gorilla VII, currently at its Sabine Pass, Tex. yard, by early December 2001. Construction on Gorilla VIII is scheduled for completion and rig release in third quarter 2003 (OGJ, Sept. 3, 2001, p. 54).
