LeTourneau Technologies will have a blank slate after its current jackup rig is delivered to sea in about a year, but its parent company, Rowan, has just purchased a Norway-based rig builder.

Rowan announced Thursday it plans to buy a majority share of Skeie Drilling, which has three, high-specification “N” Class jackup drilling rigs under construction. The deal is worth $250 million in stock, with costs to finish the rigs pegged at $420 million. The rigs can drill in 550 feet of water, tap reservoirs up to 35,000 feet deep and help expand the company’s presence in the North Sea.

Rowan will assume $530 million of first- and second-lien debt from Skeie, bringing the total investment on the trio of rigs to $1.2 billion — which company executives termed a discount over building them from the ground up.

“We are certainly turning over every stone to look to see if we can contract these rigs,” CEO Matt Ralls said during a conference call with media outlets. “You can rest assured we will be bidding in every area to try to put them to work.”

Rowan’s board of directors must approve the deal by July 19. The move means Rowan would own 50.3 percent of Skeie and half the global fleet of the high-spec rigs — those with at least 2 million pounds of hookload capacity. Like other jackups, they stand on legs on the seabed while drilling generally in waters 400 feet deep or shallower.

Also on Thursday, Rowan said it wants to move the Ralph Coffman and Bob Palmer shallow-water rigs. Both were built at LeTourneau’s yard off U.S. 61 South and, the company said, will be leaving the Gulf of Mexico due to demand elsewhere. Executives didn’t say where the two rigs would drill next and did not attribute the move to the moratorium on U.S. drilling and tighter safety regulations on all drilling in the wake of the Deepwater Horizon disaster. The announcement came a week after the company said new rules in place by the newly created Bureau of Ocean Energy Management, Regulation and Enforcement had impacted seven of its nine shallow-water rigs in the Gulf of Mexico that had contracts.

Rowan has said in regulatory filings it has no plans for LeTourneau after work on the Joe Douglas jackup wraps up by June 2011 and is delivered two months later. Ralls has said in published reports the company seeks deeper-water interests and revived talk of spinning off the local unit to another company. A move to that effect was announced in 2008 but shelved less than a year later due to the recession. About 600 are employed at the local facility.

“We’ve got prospects and quotes for some other jobs,” LeTourneau General Manager Bo-D Massey said, adding the company has continued service work to existing rigs out of the Vicksburg plant. “We’re looking for other work to bring to Vicksburg.”

The $150 million Joe Douglas is the third of the 240-C class of jackups, which can drill in up to 400 feet of water. Other specifications include an 80-feet cantilever reach and 491 feet of leg length.

Inquiries into economic development funds from the Mississippi Development Authority have started but are preliminary, Warren County Port Commission Executive Director Wayne Mansfield said.

“It’s all in case there’s a need,” said Mansfield, head of the county’s industrial development arm. “We’re trying to be proactive and retain the jobs.”