Friday, March 8, 2013

New Technology Saves 7 Days In Drilling Time

NDIC says it takes about 20 days to reach total depth.  It looks like about five days to reach vertical depth and fifteen days to reach  total depth from there. I don't read many well files, but of those I read, it doesn't seem like all that many wells are reaching TD in 20 days. I still use 30 days as a general rule of thumb. (The guys and gals in the field are probably laughing.)

A reader sent this story; it's very technical but worth reading even by a layman. High points:
  • international conference; held in Amsterdam
  • Forbes 500 oil services company: Weatherford
  • Bakken used as a laboratory (again)
  • new steering technology
  • compared two wells
  • well #2: horizontal rate with old technology: 31 feet/hour
  • well #1: horizontal rate with new technology: 38 feet/hour
  • well #2: length of lateral using old technology: 8,956 feet (failed to meed planned TD)
  • well #1: length of lateral using new technology: 10,217 feet
  • well #2: 8,956/30.67 = 292 hours of actual drilling with old technology
  • well #1: 10,217/38.08 = 268 hours of actual drilling with new technology
Conclusion of the article:
As a result of the smoother wellbore, the operator had a trouble-free casing run in Well #1. The system consistently achieved more than 93% rotation in the lateral in both wells. This was a significant improvement from previous wells, which achieved roughly 70% rotation. On the first well, sliding time was reduced from 30% to 8%, saving seven days of rig time and the associated drilling costs.
As drilling progressed, these wells required frequent directional updates, due to formation faults. Consequently, this required many target changes for geosteering. ROPs in the first Bakken well were higher than the second well, since more time was spent sliding to correct the well path on #2 without TBS technology. Use of TBS technology on Well #1 enabled the operator to have precise steering control and drill a smoother wellbore. The second well reached TD early, due to an inability to overcome high frictional forces in the lateral leg.
From the linked article, this is the technology:
To improve performance in these [Bakken] laterals, operators have been looking for a while now, for an economic alternative to rotary steerable systems (RSS’s), while still retaining their basic benefits.

Lead author Wendell Bassarath said that a new system to achieve 3D directional control was developed to improve drilling efficiency, using targeted bit speed (TBS) technology. The system uses a conventional positive displacement motor with a bent housing and an MWD tool that mimics many of the features offered by an RSS. The steering technique was achieved by accurately modulating the flow of the drilling fluid through the drillstring.

This allowed rapid variations in the drilling parameters to accurately control the bit speed along the desired toolface setting. If wellbore objectives could not be achieved in rotary mode using TBS technology, then the mud motor could be oriented in a conventional manner to follow the well plan.

6 comments:

  1. here is a Debbie Downer link to Motley Fool.

    http://beta.fool.com/grahamsway/2013/03/08/be-cautious-fracking-boom/26054/?source=eogyholnk0000001

    Crager

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    1. I can't comment on financial aspect of their comments; they are a lot smarter than I am.

      This is their lede:
      The oil & gas industry has a tendency to go into mini-booms. Often things look very promising and money enthusiastically flows into the space. Unfortunately, in many cases, things don't quite meet expectations and investors suffer. The latest mini-boom in the industry seems to center around "fracking."

      This is quite some "mini-boom" in the Bakken: it started in Montana in 2000, in North Dakota in 2007 -- so either 13 years or 6 years old and no sign of abating.

      This is quite some "mini-boom" in the Bakken: it now accounts for 12% of US oil production and continues to grow, even while oil production on federal lands is decreasing.

      This is quite some "mini-boom" in the Bakken: singularly responsible for the resurgence of American railroad industry.

      But yes, it's expensive. But as noted, I can't comment on the financial end, but if the Motley Fool writer is correct, there are a lot of investors (and analysts) that see it much, much differently.

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  2. Bruce,

    Do you have the link to the article you mention? I would like to read it. Sounds like they may be talking about Rotary Steerable System, but I would like to see what they are talking about. Thanks.

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    1. I'm sorry. I forgot to put in the link.

      I will add the link to the main post.

      But here it is:


      http://www.worldoil.com/TBS_technology_optimizes_Bakken_shale_drilling.html

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  3. Bruce,

    I did some research on the technology called "Targeted Bit Speed" technology. Not sure that it could be or would be a game changer in North Dakota. The lateral runs they quoted in the article were actually what I would consider poor runs. One well had 4 bit runs in the lateral. Last well I drilled had 1. Consider each bit trip in the lateral takes 12-24 hours depending on depth. Minimizing your bit trips alone is a gigantic factor in drilling quick laterals in the Middle Bakken or Three Forks formations.

    The directional companies have tried RSS (Rotary Steerable Systems) in North Dakota, but have not found the technique to be cost effective in the Bakken due to high costs of the RSS method. The TBS Technology is not the same thing as RSS, It basically has a flowrate modulator in the MWD tool that rapidly changes flowrate across the drilling motor depending on the rotational orientation of the drilling motor. While I suspect the system would work, the current system we utilize (bent motor and sliding for orientation) works pretty darned well in the Bakken, even in long laterals.

    Wish I could be more cheery about dropping drilling days utilizing this technology, but I do not think this will be the Holy Grail of the Bakken based on my experience. I think the biggest factors in dropping drilling days will be increased reliability of drilling rigs and downhole mud motors/mwd tools and experienced rig crews who can trip pipe quickly. Most operators in the Bakken are now utilizing more or less the same drilling methods with little variation. I suspect we are approaching the low end of Spud-TD on some of the better wells. As I said, experience and equipment reliability will be the biggest factors going forward in my opinion.

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    1. I don't know enough about drilling to comment, but it was rewarding to see, again, the Bakken being used as a laboratory.

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