Deepwater Horizon BP analysis

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Pigeon
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Deepwater Horizon BP analysis

Post by Pigeon » Sun Jan 24, 2016 8:09 pm



The best laid plans....

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Pigeon
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Re: Deepwater Horizon BP analysis

Post by Pigeon » Sun Jan 24, 2016 8:12 pm


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Pigeon
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Re: Deepwater Horizon BP analysis

Post by Pigeon » Sun Jan 24, 2016 8:12 pm


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Pigeon
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Re: Deepwater Horizon BP analysis

Post by Pigeon » Mon Jan 25, 2016 3:33 pm


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Pigeon
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Re: Deepwater Horizon BP analysis

Post by Pigeon » Mon Jan 25, 2016 8:22 pm

the beast gets loose.

A little noisy.


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Royal
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Re: Deepwater Horizon BP analysis

Post by Royal » Tue Jan 26, 2016 2:58 am

I will volunteer to PenTest the multi-million dollar engineering marvels.

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Re: Deepwater Horizon BP analysis

Post by Royal » Thu Jan 28, 2016 6:48 am

the tunnels

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Pigeon
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Re: Deepwater Horizon BP analysis

Post by Pigeon » Fri Jan 29, 2016 7:14 pm

Big crane for marine


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Pigeon
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Re: Deepwater Horizon BP analysis

Post by Pigeon » Wed Mar 29, 2017 3:11 am

The particular "botched negative pressure test" failed to make it obvious to everyone involved, whether they worked for BP or Transocean, that they had an anomalous result that needed to be resolved. They all should have stopped work and shut in the well while they figured it out. But they put the best face on mixed results and returned to work without understanding why the unfavorable result existed.

At almost the exact time the pressure instrumentation on the drill pipe was showing an increasing pressure of 1,400 psi, indicating a flowing well, the BP "company man" was on the phone to the drilling engineer ashore to discuss the test. The engineer told him that they should not have pressure on the drill pipe and at the same time have no flow through the kill line connecting the blowout preventer on the sea floor to the open atmosphere on the rig. He suggested that maybe Transocean had not lined up the test properly. Theoretically, the drill pipe and kill line were connected down below, so they should have had the same pressure at the surface. If the kill line had pressure, it should be flowing. It was not. The crew had opened the line to the surface and monitored it for 30 minutes without detecting any flow. That was what they were trying to achieve, so when they got what they both wanted and expected, they assumed that everything was all right - everything, that is, except for that 1,400-pound-per-square-inch pressure on the drill pipe.

What the crew did not consider was that there was a plug in the kill line formed by compressed "lost circulation material." This is an additive to drilling mud used to control seepage outward from the well into the surrounding porous rock. It clogs the pores of the rock, stopping the seepage. In this regard, it functions like the coagulants in blood as they form clots. It had plugged the kill line just as tightly as a clot in a coronary artery during a heart attack, with similar deadly results.

The lesson to be learned is that one proven explanation for a circumstance where you have pressure on the drill pipe but no flow through the kill line is a plug within the kill line. So how could the crew evaluate that possibility? They could pump sea water down the kill line. If there is a plug, they either will not be able to get any flow when they should, or they will eject the plug, which will result in a sudden drop in the back pressure they are pumping against. If they then stop pumping and re-check the pressure, they will then get a reading of 1,400 psi on the kill line, too. They will have resolved the anomaly with a consistent indication of high pressure indicative of a flowing well, before the well blows out. At that point, the Transocean employees in the drill shack, with the instrumentation right before them, should act in accordance with Transocean (and broader industrywide) practice and shut in the well by closing the blowout preventer without any instructions from BP or anyone else. They have both the authority and the duty to act. They need to take personal responsibility.

They could then pump denser drilling mud down the kill line (a "kill pill") to re-establish an overbalanced condition where the pressure at the bottom of the well is greater than the pressure of oil and gas in the pay zone. At that point, they could take their time doing a "squeeze job" to repair the leaky cement. Once the leak is repaired, they could continue with their plug and abandonment operation, with no deaths, injuries, pollution, or multi-billion-dollar financial losses.

Link


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Pigeon
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Re: Deepwater Horizon BP analysis

Post by Pigeon » Wed Mar 29, 2017 3:14 am

Link to time line

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