Oil well driller Helmerich & Payne's ( HP) saidthird quarter profit more than doubled. The Tulsa, Okla.-based company earned $80 million, or 75 cents a share, in the quarter, compared with $29.8 million, or 28 cents a share, a year ago. Earnings include a gain of 6 cents a share related to sale of portfolio securities and drilling equipment. Analysts polled by Thomson First Call were estimating earnings of 67 cents a share in the most recent quarter. Third-quarter revenue increased 54.2% to $319.8 million, higher than the consensus estimate of $313.8 million. Operating profit more than doubled to $114.1 million and operating profit margin improved to 35.7% from 24.8% a year ago. The company said U.S. land average rig margins per day rose from $12,567 in the year ago period to $12,938 per day and third quarter average rig revenue reached an all time high of $23,503 per day. The company expects to begin drilling operations in Tunisia with a new FlexRig3 during the first fiscal quarter of 2007.