Drilling advances

More tech companies these days are designing their mobile phones, PCs and laptops with an eye toward the end of their productive lives. “We think as much now, about the recycling and end-of-life of products, as the design of products itself,” Lisa Jackson, Apple V.P. of environmental, policy and social initiatives, told the Wall Street Journal.

What some might see as a fatalistic corporate strategy, the tech companies see as a sound business approach, and one that reduces end-of-life waste and headaches. As Dell’s director of Environmental Affairs, Scott O’Connell, said in the June 8 article, “If you don’t think about it at the beginning, with the design, it becomes a lot more complicated later on.”

O’Connell could just as well be speaking for the global oil field, which is recognizing increasingly that the manner in which a well is designed and drilled has a direct bearing, not only on maximum reservoir drainage, but also in the secure, and mandatory, abandonment once said reservoir is commercially depleted. Hans-Christian Freitag, Baker Hughes V.P. of integrated technology, practically channeled the Dell executive, saying, “We have to design at the beginning with the end in mind, and that’s secure abandonment. How do we get to a well that’s more abandonable without too many issues?”

Freitag made the comments during the June IADC Drilling Engineering Committee’s (DEC) quarterly Technology Forum in Houston, which focused on the sundry issues associated with well life cycle design. He suggests that engineering for the utmost in wellbore integrity at the onset is the be-all and end-all for delivering a well that produces at its maximum potential, but which can be abandoned with minimal complications when it reaches the end of the line. Despite the acceleration of pacesetting drilling technologies, however, the universal elimination of wellbore integrity issues remains elusive.

“I went back to 2006, and there was a Wellbore Integrity Network, and in the second meeting they had in September 2006, they came up with a profound first observation that there seemed to be a problem with wellbore integrity in existing oil and gas wells throughout the world,” he said.

Freitag pointed to a multi-agency study five years later that found 45% of the wells in the Gulf of Mexico, 34% in the UK sector of the North Sea, and 18% in the Norwegian sector still had wellbore integrity problems. “We see an astounding number of wells having integrity problems,” he said. “What we do with wells with integrity problems is try to do something with them, but normally we shut them in and drill another well to provide the production we promised shareholders. That’s highly inefficient.”

Changing mindset. DEC chairman Keith Lynch, ConocoPhillips’ global completion chief, referenced another analysis that puts total abandonment costs in the UK sector, alone, at $87 billion, or more than the aggregate costs to drill the wells. Freitag said that “hefty price tag” should provide ample impetus to drill wells, so they can be plugged and abandoned with minimal hassles. “This is what we should do, but the path for getting there is a different matter,” he said.

Transitioning to a more variable well construction environment, he said, would go a long way toward optimizing the complete life cycle. “We look at constructing a well efficiently, with no lost time and getting to the reservoir safely, and with all barriers in place. This is a very static environment that doesn’t take into account the 10-, 15- or 20-year life cycle of the well, and what happens in the reservoir and the surrounding environment during the production phase,” he said. “The production department needs to have a well that can react to reservoir pressure and other changes during the production phase.”

Of course, between the initial design, drilling and eventual abandonment, the overriding objective is to deliver a useable wellbore and one that will “continue to flow for the longest period of time,” Freitag said. For unconventional wells, many of which invariably require artificial lift, that means drilling a smooth lateral without the dips that can impede flow, said Bill Lane, V.P. of Weatherford Artificial Lift Systems Emerging Technologies. “We need to construct a straight lateral, where possible, to minimize undulations,” he said. “During drilling, we need to consider how best to drain the well from heel to surface.”

In another presentation, Sylvain Bedouet, founder and CEO of Bison Oil Tools, discussed new-generation plugs, comprising a bismuth-based metal alloy that is melted in-situ via a chemical reaction heater to provide a gas-tight seal even, he said, in corroded or damaged casings. For both abandonment and intervention purposes, he says the metal plugs provide a more reliable alternative to commonly used elastomer seals. “We’re still using elastomers for nearly all sealing downhole, even though we know that elastomers do fail. It is our belief that trying to get a gas-tight seal in a corroded well with elastomers is more or less impossible,” he told the DEC.

Game-changers. Freitag singled out steerable drilling liners and wired drill pipe as reflecting the technologies that have profoundly elevated the industry’s ability to access reservoirs efficiently. “We can navigate today with a degree of accuracy that people would have believed impossible just five years ago,” he said.

All well and good, but what about ensuring that the well maintains integrity throughout its useful life? As fantastical as it may appear on surface, intelligent and self-healing cement is not that far from reality, Freitag says. “Just imagine, and it’s not far off, a cement that assesses its own integrity through the life of the well. Take the Gulf of Mexico, for instance, where we have issues with casing deformation and so on. Imagine a cement that not only diagnosis itself, but heals itself.” 

About the Authors

Jim Redden

Contributing Editor

Jim Redden is a Houston-based consultant and a journalism graduate of Marshall University, has more than 40 years of experience as a writer, editor and corporate communicator, primarily on the upstream oil and gas industry.