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This month in history: BP sets record
20 years ago this month: company sets CTD world record at Niakuk; technology may allow sidetracks to 4,000 feet Kristen Nelson Petroleum News
Editor's note: This story first appeared in the Oct. 10, 2004, issue of Petroleum News.
BP Exploration (Alaska) has recently set development drilling records on Alaska's North Slope with technologies targeted at oil accumulations that are smaller and often farther from infrastructure, and with technologies developed to aid in production of viscous oil, which is colder and thicker than the slope's conventional crude and doesn't flow as readily.
Members of BP's Alaska drilling group talked with Petroleum News Sept. 28, 2004, about the company's development drilling program, the recent drilling records and about the technology that is driving the company's program.
Gary Christman, BP's Alaska drilling and wells manager, said the 129-person drilling organization monitors some 2,000 wells BP has on the North Slope and keeps eight rigs busy: five rotary rigs, two coiled tubing drilling rigs and one rotary workover rig.
"Within the BP portfolio we're the third most active drilling and wells organization worldwide," Christman said, behind Argentina and the Lower 48. BP expects to see that level of activity continue, with capital spending in Alaska expected to be "pretty steady over the next five years," after which the company hopes to see drilling at its Beaufort Sea Liberty prospect, and gas development.
In addition to being a "good, steady piece of very important work for BP," North Slope development drilling has also been "a technology incubator" for the corporation over the years, Christman said. New technologies have been developed on the North Slope, and continue to be refined, he said, noting in particular coiled tubing drilling, and the use of multi-lateral drilling to access viscous oil, with recoverable reserves (with current technology) of 1.6 billion barrels.
He said coiled tubing drilling was "taken from an idea and germinated ... into a technology that's a key part of our portfolio."
Technology developed in Alaska is exported to other operations, but also helps Alaska. "We continue to show year-on-year performance improvements through the effective use of new technologies, as well as the techniques that we employ in the drilling and completion of our wells," Christman said.
"So, our capital efficiency, despite the fact that we're going after smaller and smaller accumulations of oil, tends to be flat or improving on an annual basis, so performance improvement has been on, and remains on, a good trend for continuation."
The measures BP uses to compare Alaska's operation to the company's other business units include number of days to drill 10,000 feet; reserves added per million dollars of investment; capital employed per thousand barrels of oil a day; number of days to complete a well; and number of days to put a well on production after it has been completed.
Coiled tubing drilling plays major role Coiled tubing drilling plays a major role in BP's efforts to produce its North Slope fields "as efficiently as possible and get the most oil out of those mature fields," said BP senior coiled tubing drilling engineer Mark O. Johnson.
BP set a coiled tubing drilling record at the Niakuk field in March 2003: "We drilled to 17,500 feet, which was a world record with coil," he said.
Coiled tubing was first used for drilling in Alaska in 1993-94, and the technology, used to reposition the bottomhole of a well where the original well has petered out, has been developed over those 10 years.
A 15,000-foot tube is put on a reel and snaked into an existing well "with a bit and a motor on the bottom of it" and used to sidetrack out of an existing well bore to a new bottomhole location, Johnson said. The sidetracks are usually horizontal and are in the 2,000- to 2,500-foot range.
Coiled tubing drilling costs less than rotary drilling, Johnson said, and allows drillers to get "to trapped pockets of oil at a lower cost than alternative methods."
Downhole tractor trials BP is trying to improve on coiled tubing drilling technology so that it can drill longer horizontal sections with coil, perhaps up to 4,000 feet Johnson said, and is testing a downhole tractor that will help pull the drilling bottomhole assembly.
A bottomhole assembly, some 100 feet in length, is the drilling end of the coiled tubing and includes the bit, a motor and other tools.
A bottomhole assembly has a motor behind the bit that turns the bit by pumping fluids through it, "but you have to have weight" behind the bit, Johnson said, and the limitation of coiled tubing drilling is that you can't push that hard on the 15,000-foot coiled tubing, "it's kind of like pushing a noodle."
If you can't push, you can pull, and BP is testing a tool called a tractor, designed to pull the coil at the end, with the goal of extending the length of horizontal sidetracks that can be drilled to as much as 4,000 feet.
The tractor is added to the bottomhole assembly just behind the motor. The tractor is about 22 feet long and about 3 inches in diameter and has arms that extend wheels out to grab onto the hole that has been drilled, pulling the coiled tubing along.
The tractor has "been tested now in two wells with encouraging results, but it's definitely in the testing phase," Johnson said.
BP doesn't know yet if this will work, "and this is what we have to do with coiled tubing drilling all the time: we come up with an idea and we test it. If it works, we run with it. If it doesn't, then we go on to something else."
Leading edge for BP Alaska represents the leading edge at BP in using coiled tubing drilling "on a regular basis and improving it," Johnson said. BP has drilled more than 50 sidetracks a year with coiled tubing drilling and has two rigs in continuous operation, he said.
The majority of the coiled tubing drilling sidetracks are at Prudhoe Bay, but one of the rigs is currently working in the Kuparuk River unit, and the company has also done coiled tubing drilling at Endicott, Milne Point, Lisburne, Point McIntyre and Niakuk.
BP's Alaska coiled tubing drilling experience is also being shared around the world, Johnson said, with a recent successful gas drilling project at the Sajaa field in Sharjah in the United Arab Emirates.
"Technology developed here is being used there by BP and very successfully, and they're feeding back ideas to us that we're using and they're helping our program."
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