Deepwater Horizon ROV BOP photo

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Cool stuff.

Pic of an underwater ROV attempting to operate the blowout preventer on the leaking wellhead: http://www.flickr.com/photos/uscgd8/4551846015/

"Once we got to the point where twenty/something's needed a place on the corner that changed the oil in their cars we were doomed . . ."
-NickDG

[GeorgiaDon 340]

Thanks for posting that link. The comments are very educational. Most are from engineers involved in the oil industry, proposing and critiquing possible solutions. I now have a much better understanding of what may have gone wrong, and why the problem is so difficult to fix. Very different from the usual string of illiterate imbecilic rants that follow most internet postings (not to cast aspersions on SC!).

Don

_____________________________________
Tolerance is the cost we must pay for our adventure in liberty. (Dworkin, 1996)
“Education is not filling a bucket, but lighting a fire.” (Yeats)

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Yeah, I've been reading the comments. Very interesting. There are some links in the comments that show drawings/pics of the riser that fell to the ocean floor. More underwater pics here: http://www.flickr.com/photos/uscgd8/.

"Once we got to the point where twenty/something's needed a place on the corner that changed the oil in their cars we were doomed . . ."
-NickDG

[rwieder 0]

Pics And Sonar Of Deep Water Horizon's Resting Place

There also literally hundreds of links loaded with first hand accounts of crew members speaking to the media. Bad move on their part, IMHO.

The odd thing about that ROV attempting to close the "Blind Shear Rams" is the switch is set toe the "OP" position. If they could just get the Blind Shears to close they would slam shut cutting & shearing anything in it's path & the flow of hydrocarbons & massive amounts of methane gas would be stopped from flowing. My fear is the storable bottles of NO2 mounted on the Sub Sea BOPE package have been depleted. Remember prior to this well control event they were displacing the riser itself with sea water before the disconnect of the riser to the well head, with drill pipe in the riser. this considerably reduces the hydrostatic pressure inside the riser itself. Because they had ran a liner, cemented it and hung it off the wellhead itself, this tells me that the cement job may have possibly "Channeled" and they didn't have a sufficient bond around the circumference of the liner which would serve as a completion casing. I don't have any information concerning this topic, but if it had been me, after the cement job I would have pulled approx 4-5 hundred feet above the liner top, reverse circulated a minimum of two times, secured the well and observed the backside, or casing pressure to insure no influx of formation fluids were entering the wellbore. Your casing pressure will build some because of the cement activation ingredients generating heat, which causes expansion generating casing pressure, but if they had the cement lab results on board they would have known how much expansion and pressure to expect. Remember when we drill these wells no matter where you are we control them with our mud weight which compensates for formation pressure, the higher the "Pore Pressure" the higher the mud weight needs to be to keep hydrocarbons in the formation utilizing more hydrostatic pressure with a higher mud weight. Hydrostatic pressure = MW X 0.052 X TVD (True Vertical Depth) MW = (Mud weight of mud utilized during the drilling process) 0.052 = A mathamatical "constant" You can relate hydrostatic pressure much like swimming to the bottom of a 22' deep swimming pool, you can actually feel the hydrostatic pressure on your body, divers should be acclaimated to this feeling that hydrostatic pressure exerts on their bodies. A riser disconnect from the well head is a simple process and usually always uneventful, however this time it was evenful.

-Richard-
"You're Holding The Rope And I'm Taking The Fall"

[TrophyHusband 0]

where the fuck is chuck norris in all this and why hasn't he stopped this yet?

"Your scrotum is quite nice" - Skymama
www.kjandmegan.com

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Rwieder,

I read that the shear rams on a BOP cannot cut through a "tool joint" Is that true? Does the successful operation of the shears on a BOP require that the string be positioned such that a joint not be at the shears? Thanks.

"Once we got to the point where twenty/something's needed a place on the corner that changed the oil in their cars we were doomed . . ."
-NickDG

[rwieder 0]

Quote

I read that the shear rams on a BOP cannot cut through a "tool joint" Is that true? Does the successful operation of the shears on a BOP require that the string be positioned such that a joint not be at the shears? Thanks.

They are designed to shear through anything. Chances are they would shear through a "tool joint" on drill pipe, but bear in mind, there was no drill pipe inside the sub sea package at the time of the well control event. If the shear rams would have been operable (And I don't know they weren't) they should closed and sealed the well off. They had set cement plugs in the casing to T&A the well (Temporary Abandon) and that should have created a "Barrier" You always have to have at least 2 barriers. One barrier was the casing that was cemented in place, the other, the cement plugs that were set in place, (As Per MMS) and they had a 3rd barrier w/ the sub sea package. It's hard to understand how a sub sea BOPE package works because you can't see it, all of the "Floaters" I've been on have had ROV's w/ cameras and you could see anything you wanted, big huge gigantic fish swimming around etc...What I know from what I've researched so far is they were merely displacing drill mud out of the riser with sea water (Which is common) in preperation to disconnect from the sub sea well head to move either port, starboard, bow or the stern position to finish pulling the 4800' or so of drill pipe, then pull the 17 1/2" riser. Cosequently reducing the amount of hydrostatic pressure indide the riser. Riser is simpley the pipe that connects on top of the "Knuckle Joint" of the upper most annulur preventer to allow movement, kind of like a ball joint works on your A frame on your car. It then enables lowering the sub sea package to the sub sea well head which is then set in place and latched via remote control via the surface controls on the rig floor. The riser goes to the surface where a "Slip Joint is placed under the rig floor inside the "Moon Pool. Each "Floater" has a sub sea engineer, I'm not clear on whether he was amoung the missing or not, but he, or one of the rig managers would be in the position to answer that.

-Richard-
"You're Holding The Rope And I'm Taking The Fall"

[1969912 0]

Right, no drill pipe. But if they were in the process of replacing the mud with seawater, wouldn't they have a string of some kind of pipe in the well in order to pump seawater in and slurry the mud back up to the drill rig? Something is keeping the BOP from shearing and sealing the well. If the cement plugs failed, could they be shoved up through the casing and mash whatever pipe was hanging from the rig into a big blob inside the BOP that is impossible for the shears to cut? Could a casing failure allow casing to be squished up into the BOP?

Thanks for the info.

"Once we got to the point where twenty/something's needed a place on the corner that changed the oil in their cars we were doomed . . ."
-NickDG

[1969912 0]

From what I'm reading, there WAS drill pipe in the well. Perhaps that's what was being used as a seawater conduit to displace the mud. There is still talk about a tool joint being at the BOP shear line and the BOP rams are unable to cut it. Here is a pic of the riser at its lowest point: http://twitpic.com/1m8f4c.

Edit: The top of the BOP is ~10 feet below the bent riser in this pic, and is not visible.

"Once we got to the point where twenty/something's needed a place on the corner that changed the oil in their cars we were doomed . . ."
-NickDG

[rwieder 0]

What you see in that photo is merely the riser collapsed to the left while it's still attached to the knuckle joint. It wouldn't matter if there was any drill pipe there, a simple move of a joy stick at the driller's cyber chair and it's outta there. Why would they have drill pipe in the Sub Sea BOPE Package? You don't need to worry about having drill pipe in the BOPE Package or anywhere near to Liner Top that has been sealed in the Sub Sea Well Head and a Sucessful Positive-Negative test having been performed? I believe this well control event may have been caused by channeling cement. I really don't like to discuss it but back in 1997 when I was a Drilling Foreman on a ****** Rig # 238 in Union Hill Louisiana we experienced much the same phenom. We had drilled the well succesfully, and we did the production part of the well with the drilling rig. We set our packer, performed a positive negative test at the packer top, and it was succesful. So we ran 3 1/2" tubing, stung into the packer, spaced it out and landed it in the well head, and tested the pack off and the void to 20K. We knew BHP was 12K-15K. Everything was going great until we went to NDBOPE Package. We got the Rotating Head on the cellar floor and next thing you know....BLAM...Raw gas at the surface near the wellhead. 1 minute later ignition, 15 minutes later the derrick was in the reserve pit and the rig was a total loss. Cement channeling is a problem. Another Operator had a well accross the street from ours, it was already in production status, next thing you know, there was drilling mud coming out on the surface from approx 15K BGL. They built a gigantic reserve pit around it and they were hauling off oil and salt water for the entire time I was there.

You'll notice that on each side of the riser, there are 3" lines that run on each side of the riser to the surface, that is the choke & kill lines that go to our remote control panel, we use these lines to accuate our Sub-Sea BOPE Package.

-Richard-
"You're Holding The Rope And I'm Taking The Fall"

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This is crazy!

Quote

"Under scrutiny from officials in his own agency, the local Minerals Management Service engineer who approved BP's application to drill under the Deepwater Horizon admitted that he approved the blowout preventer that failed to stop the Gulf of Mexico oil spill without assurances that its last-ditch mechanism would work on the drill pipe the company was using.

Jason Mathews, an MMS official who sits on the six-member joint Coast Guard and MMS investigative board, questioned Frank Patton, the agency's New Orleans District drilling engineer, about his approval of BP's drilling permit. Mathews noted that MMS regulation 250.416(e) requires would-be drillers to submit proof that the blowout preventer they are using to shut off the well will have enough power to shear a drill pipe in case of an emergency.

Those mechanisms on the 450-ton blowout preventer at the bottom of the seabed are called blind shear rams, a pair of high-pressure valves and blades that are supposed to slice through a gushing drill pipe and close off a well leak. But attempts to get those shear rams to operate on the well below the Deepwater Horizon have been unsuccessful since the April 20 disaster.

Patton testified he was not aware of any such requirement and never demands it from more than 100 applications his office reviews each year.

"I have never been told to look for this statement," Patton said. The BP application had "no information on blind shear rams' ability to shear the drill pipe used."

"If they didn't submit it, why did we approve it?" Mathews asked.

"That is one thing I don't look for in my approval process," Patton said. "I've never looked for that statement there."

"Is this just you, or is this MMS-wide? " Mathews persisted.

"I'm not sure," Patton said sheepishly.

Another MMS official on the panel, John McCarroll, continued to put the pressure on. He asked if Patton was aware of a 2004 study for MMS by WEST Engineering that found problems with blowout preventers shearing heavy drill pipe. Patton said he wasn't. McCarroll asked him when he took over as the permitting engineer in New Orleans. Patton said 2008.

"And that report was written in 2004," McCarroll repeated.

From: http://www.nola.com/news/gulf-oil-spill/index.ssf/2010/05/updates_from_oil_rig_explosion_1.html

WEST engineering BOP study is here: http://www.mms.gov/tarprojects/463.htm

"Once we got to the point where twenty/something's needed a place on the corner that changed the oil in their cars we were doomed . . ."
-NickDG