The Blow-Out Preventer

A relatively simple device: The Blowout Preventer

It’s mandatory in Norwegian offshore oil drills. It’s mandatory in Brazilian offshore oil drills. It is not mandatory in oil drills off the US coast.

It could have prevented the latest spill.

But. You had the oil industry effectively on the helm of your country for too long. And, without effective regulation, they won’t even begin to consider using these – costs you know.

UPDATE:  See more information regarding the oil spill by commenters TerrytheTurtle, houseofroberts, 2ebbandflow, and Hoodathunk here, here, and here.

UPDATE II: TerryTheTurtle has made us aware of a valuable source, for those who are following the research of the oil spill’s cause. You will have regular updates here and another article based on a European source can be found here.

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23 thoughts on “The Blow-Out Preventer

  1. EV, there was a BOP on the sea bed. That was not the issue.

    The issue was that it failed to operate. How is unclear, but the fact that the robots could not manually override it and close it is very telling indeed.

  2. So if we assume that this assembly is 5000 feet under water, the water pressure is about 2500 psi (I derive that from normal atmospheric pressure = 15 psi * 5000 feet / 30 foot water column at normal atmospheric pressure). All numbers are approximate. This means that sending a diver down to solve the problem is a mute point.
    What roils the issue in my own mind is that a simple stop-cock or interrupt valve could have stemmed the low if it had been in place. The problem is that such devices are priced like insurance polices. While costing a few thousand dollars to manufacture, their prices are based on their potential protective value. Scarcely a way to run an economy or any industry.

  3. Walt these are not your granddad’s stopcocks…. scuse me – I said c***.

    These things are the size of a room, rated to 5000psi and cost millions of dollars to make.

    They are complex devices, requiring extremely high tolerances on manufacture and performance.

    They are designed to fail safe, meaning you ahve to work hard to open them and then you need to keep a bunch of active and passive controls to keep them open.

    Its clear to me, since BP can’t close this one using a robot on the manual override that this one has failed.

  4. I see that the accepted rate of release is now 5000 bpd and not the original 1000. That means Exxon Valdez scale by about mid June.

  5. The well had a blowout preventer (known as a BOP). EVERY well drilled, virtually anywhere in the world, has a BOP mounted on it.

    What was missing was a acoustic device that would allow a closing signal to be sent from the surface. It’s required in some parts of the world, not in the US.

    Obviously something went wrong, and it’s more complex than this one missing item. First, we don’t know what caused the fire and explosion that sank the rig. Second, usually there are “dead man” devices that should close the BOP and securely shut in the well whenever contact is lost with the surface vessel. Third, I’m also curious about why they weren’t able to close the BOP using an ROV (Remotely Operated Vehicle, basically a robotic submarine).

    It will turn out to be human error, we don’t know whose. But it will cost BP millions and it should. Somebody f***ed up big time.

    On the other hand, before anybody else gets too sanctimonious: unless you’re living off the grid, bike everywhere you go, get all your power from renewable sources, raise your own crops without chemical fertilizers: almost all of us depend on power from fossil fuels. We use gasoline in our cars, or jet fuel when we fly, or electricity generated from fuel oil, natural gas, or coal. The task is not without risk. It needs to change but most of us are not yet willing to pay two or three times to go all green.

    BTW, that is a simplified picture of a BOP arrangement, intended for a land well during well repair (not drilling). A subsea BOP stack is more complex and includes a control system and power supply.

    • marzolian, last thing I heard, which is discussed lively here in Europe is, the well didn’t have one. But as my point is a different one, namely that regulation may be a bad thing for corporations, but it’s a good thing for us. So don’t let corporations own government, it will in the end only hurt you.

      When you said:

      What was missing was a acoustic device that would allow a closing signal to be sent from the surface. It’s required in some parts of the world, not in the US.

      You didn’t exactly prove my point wrong, did you?

  6. ElmoTheGrape at TP had this link. I know it’s Faux, but the guy being interviewed is the poster himself. The blog is certainly on the left, so I take his explanation as plausible.

    Bob Cavnar Gives Possible Scenario For Blowout

    This looks like it could have been a backside blowout, which means it actually blows out, on the outside of the pipe, not the inside of the pipe, and because there was a setting tool, inside the blowout preventer, that kept them from closing that blowout preventer.

    • HoR, good link to the video. I am not really into engineering things and had difficulties following the guy, but God forbid I had that vacant stare that the blonde girl had :D

      The explanation, however, was really interesting. I will check into that a little more, but I am afraid the real reason for the explosion will not be known for a while. At least until BP gets dragged into court and forced to explain. I am sure, however, no matter what Fox tries to do and that blonde really tried hard, no foul play was involved.

  7. I fully agree with your main point, which was that the corporations shouldn’t control the regulators.

    But you started with a mistatement about which equipment was missing.

    From what I read in other sources, the need for an “acoustic switch” is debatable. For instance, if the BOP won’t close for some mechanical reason, then an acoustic signal would not be helpful.

    Furthermore, you seem to be saying that there is no regulation at all. There is quite a bit; not as much as in Europe, and there should probably be a bit more regulation. But it’s simply not correct to claim that there is no oversight at all. And even with independent regulators, mistakes happen. Even in Europe.

  8. marzolian, I am keeping track on the causes of the oil spill. I am fully willing to correct myself or this post, if necessary. I am unwilling, however, to get myself in a discussion about this is debatable, that is debatable, which only serves to take the point away.

    I said nowhere, there was no oversight, I said “without effective regulation”, right?

    Corporations, who have way too much influence in your political system, and in ours, try to water down all regulative legislation and often succeed.

    Look at what’s happening to the financial markets regulation planned by your current administration!

    The Hill is swarming with lobbyists.

  9. It’s been reported that the Deepwater Horizon well had a blowout preventer, but that it did not work correctly. Although it is not a requirement to install a Blowout Preventer (or Christmas Tree as it’s called in the industry), many companies do because of the savings in cases like this (if the Blowout Preventer had worked properly it would have prevented much of the spill).

    The issue in the case of the Deepwater Horizon is not whether there was a Blowout Preventer or not, but why safety measures put in place did not work in this case.

    • jessica2514, welcome to the Zoo. I recommend you follow comments in our threads. Our regular commenter Terry The Turtle is closely watching the coverage pertaining to the cause of the spill and he is regularly posting updates. I think the jury’s definitely not in on that.

      My issue in the case is, however, wouldn’t strict regulation and controls help keep the oil companies on their toes ?

  10. jessica2514, you are repeating a mistake made by several news reports. I grew up and worked in the oilfield for many years, and I’m amazed how poorly the mass media reports on the equipment and processes used in the oilfield, especially with a fast-breaking story such as this one. However, they seem to learn after a few days.

    A blowout preventer (BOP in the trade) is NOT the same thing as a Christmas tree. A BOP is a safety device that is installed on a well while it is being drilled, and at any time after that when work is being done and there is the possibility that the well might have sufficient pressure to flow out of control.

    A Christmas tree is installed on a well after the drilling is finished, during an operation called the “completion”. It remains on the well for as long as the well is producing.

    This Wikipedia article is not perfect, but it gives a reasonable explanation of a Christmas tree:

    http://en.wikipedia.org/wiki/Christmas_tree_%28oil_well%29

    It is not only a good idea, but it is a legal requirement to have BOP equipment on a well, and that is anywhere in the world. It would be impossible to control flow from high-pressure zones of the well without it.

    What was missing from the Transocean rig was an acoustic switch, which is a device intended allow the BOP to be operated even when there is no direct physical connection to the rig on the surface. However, given that the company has been unable to operate the BOP using ROV’s (robotic submarines), it’s not likely that an acoustic switch would have helped this time.

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