Deep Water Horizon - Gulf of Mexico

[emicen]

Yes, I know its a while back now but found this interesting:
http://deepwater.com/fw/main/Blow-Out-Preventor-(B...

Shows how it all unfolded.

[Brother D]

emicen said:

Yes, I know its a while back now but found this interesting:
http://deepwater.com/fw/main/Blow-Out-Preventor-(B...

Shows how it all unfolded.

Thanks for that ! - Good explination

[Ozzie Osmond]

Hmmmmm.

Do we therefore conclude that,
i) the Blow Out Preventer was never capable of preventing a blow-out? or
ii) the BOP would have worked just fine if only it had been one specific diameter of BOP used with one specific diameter of pipe? or
iii) this blow-out was so big that nothing could possibly have stopped it?

[srebbe64]

Fascinating. If I've interpreted it correctly (and that's a big if) it's amazing how much friction was caused by 'fluid' - presumably oil ???

[anonymous-user]

Ozzie Osmond said:

Hmmmmm.

Do we therefore conclude that,
i) the Blow Out Preventer was never capable of preventing a blow-out? or
ii) the BOP would have worked just fine if only it had been one specific diameter of BOP used with one specific diameter of pipe? or
iii) this blow-out was so big that nothing could possibly have stopped it?

i was thinking more the pressure capabilities, i presume this BOP was never supposed to work at such this great pressures. i wonder if BOP are designed for specific drilling areas or generic.

[Mr Sparkle]

Very interesting, thanks for posting.

So the shear rams should have isolated and sealed the lower section but the pressure was too great and the fluid just tunneled through the steel? Would think this means it was designed or spec'ed incorrectly. I wonder of the pressure compares with that experienced at other sites where a BOP has been successful.

[DonkeyApple]

This would mean that it was the fault of TransOcean as BP have claimed all along.

As such, what are the chances that BP's money is involved in that article somewhere?

[Stylus]

DonkeyApple said:

This would mean that it was the fault of TransOcean as BP have claimed all along.

As such, what are the chances that BP's money is involved in that article somewhere?

That's the website of Transcocean and the finding of their internal report.

[emicen]

srebbe64 said:

Fascinating. If I've interpreted it correctly (and that's a big if) it's amazing how much friction was caused by 'fluid' - presumably oil ???

Mixture of oil, gas and drilling mud. High pressure and velocity grinding paste effectively.

[Parrot of Doom]

Regardless of blame, it just looks like one big old-fashioned cock-up from which, hopefully, everyone will have learnt an expensive lesson.

[The Black Flash]

Fascinating stuff. You can see why it was so hard to fix - everything got locked up, then it crimped the top off for good measure. It's hard to imagine a worse scenario.

It would seem, from my layman's point of view, that some design changes are in order.

[Ozzie Osmond]

The Black Flash said:

It would seem, from my layman's point of view, that some design changes are in order.

Absolutely agree. Looks like a Blow Out Preventer with the minor problem that it wasn't actually capable of preventing a blow-out. Or at least, not this blow-out.

If this particular blow-out wasn't foreseeable the fact is that the next one IS foreseeable. Assuming the BOP was a standard piece of equipment we now know for certain that the ocean floor is littered with oil wells fitted with BOPs which don't always work.

[Stylus]

Ozzie Osmond said:

Absolutely agree. Looks like a Blow Out Preventer with the minor problem that it wasn't actually capable of preventing a blow-out. Or at least, not this blow-out.

If this particular blow-out wasn't foreseeable the fact is that the next one IS foreseeable. Assuming the BOP was a standard piece of equipment we now know for certain that the ocean floor is littered with oil wells fitted with BOPs which don't always work.

Not really....

This well was being drilled in an area that is relatively new with pressures and temperatures that do provide challenges (as obviously happened). The BOP is a proven bit of kit, however in this case the data provided beforehand on the pressures to be expected while drilling were wrong (too low) and so the BOP was inadequate.

In a mature area, the North Sea for example, the pressures are known and drilling doesn't throw up surprises as big as what happened in the GoM.


Additionally, you'll notice I'm only talking about drilling wells. The wells scattering the ocean floor are on 'production'. Here a different surface (seabed) containment method is used - a tree and wellhead outlet. These are only fitted after drilling is complete, and as such you will have already seen any pressure hikes during drilling, and subsequently spec'd them to match.
Furthermore, you will have valves down in the wells themselves (Safety Valves) which will close if communication is lost from surface (rig being disabled), and will shut the well in automatically.

Hope that helps.

[The Black Flash]

Stylus said:

This well was being drilled in an area that is relatively new with pressures and temperatures that do provide challenges (as obviously happened). The BOP is a proven bit of kit, however in this case the data provided beforehand on the pressures to be expected while drilling were wrong (too low) and so the BOP was inadequate.

Cheers for the info.
Given, though, that this is the last-ditch safety device in case of complete and utter balls-up, I'm amazed that they're not always specced to deal with the highest known pressures.

The very fact that it is there to deal with the unforeseen, surely means that you shouldn't assume anything?

I'm not pretending to know much about this stuff, but I'd be surprised if new BOPs didn't sprout improvements in the light of this accident.

[BrassMan]

The Black Flash said:

Stylus said:

This well was being drilled in an area that is relatively new with pressures and temperatures that do provide challenges (as obviously happened). The BOP is a proven bit of kit, however in this case the data provided beforehand on the pressures to be expected while drilling were wrong (too low) and so the BOP was inadequate.

Cheers for the info.
Given, though, that this is the last-ditch safety device in case of complete and utter balls-up, I'm amazed that they're not always specced to deal with the highest known pressures.

The very fact that it is there to deal with the unforeseen, surely means that you shouldn't assume anything?

I'm not pretending to know much about this stuff, but I'd be surprised if new BOPs didn't sprout improvements in the light of this accident.

The kit is pretty reliable, I'm as work so haven't seen the video yet, but I'd assume that it came down to human error (maintenance or operation) or another failure elsewhere.

[Beardy10]

That is very interesting....it seems like Transocean are looking to portray it as a series of unfortunate occurances ?

I suspect ultimately it will come down to a combination of errors on the part of Transocean (operator), BP (majority owner) and Haliburton (logisitics/construction) though obviously BP being British are in the cross hairs more.