UPDATE 1-GlobalSantaFe 1st-quarter profit more than doubles

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HOUSTON, May 2 (Reuters) - Offshore driller GlobalSantaFe Corp. GSF.N said on Wednesday its net profit more than doubled, helped by higher prices for its rigs and one-time gains from insurance payments.

The Houston-based company reported a net profit of $347.4 million, or $1.49 per diluted share, compared with $162.9 million, or 65 cents per diluted share, in the year-earlier period.

Excluding after-tax gains related to insurance payments and other items of $48.2 million, or 21 cents per diluted share, 2007 first-quarter income was $299.2 million, or $1.28 per diluted share.

On that basis, Wall Street analysts on average had expected a profit of $1.23 a share, according to Reuters Estimates.

Revenue in the quarter rose to $903.5 million from $679.4 million a year earlier.

"Our improved first quarter results reflect solid operating performance and ongoing strength across international offshore drilling markets," GlobalSantaFe President and Chief Executive Officer Jon Marshall, said in a statement.

The average revenue per rig per day rose 58 percent to $159,500 during the first quarter of 2007 from $101,000 a year earlier.

The shares of Houston-based GlobalSantaFe closed up 1.2 percent, or 77 cents, at $65.24 on the New York Stock Exchange.