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2010-06-16 -Short Attention Span Theater-
Boy, 10, shows how to stop oil
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Posted by gorb 2010-06-16 03:32|| || Front Page|| [3 views ]  Top

#1 Dumb.
Posted by Phosing Big Foot3926 2010-06-16 03:59||   2010-06-16 03:59|| Front Page Top

#2 One small problem Charlie. There are two strings of 5" drill pipe inside the riser.
Posted by junkirony 2010-06-16 08:44||   2010-06-16 08:44|| Front Page Top

#3 I suppose there is no way to pull out the drill pipe, eh?
Posted by gorb 2010-06-16 10:15||   2010-06-16 10:15|| Front Page Top

#4 gorb, there are a log of problems with the idea. I recommend 'The Oil Drum' for extensive discussion on the complexities of trying to control this well. For starters: lots of oil blowing in your sensors so you can't see once you get nuts loosened, the pipe is likely pratly crushed and pinned below the flange, tough to maneuver a plate into place with a vicious cross-flow, and even if you succeeded, the added stress on the upper part of the well could cause it to break off and lead to an even more uncontrollable situation.

junirony, there shouldn't be but one string of drill pipe in the riser - the pictures of the clipped riser look like two, side-by-side, but it could be just a a short little stub that slipped in somehow and got cut a second time, or it could be a stub of 9 7/8" casing bent into a figure 8 and no drill pipe.
Posted by Glenmore 2010-06-16 10:58||   2010-06-16 10:58|| Front Page Top

#5 One thing that has me puzzled. The BOP is supposed to be able be removed and replaced in case of a problem. It can supposedly be pulled up, repaired and put back in place.

That the BOP has not be removed, another put in its place and the new one "fired" has me a little bit baffled. This would seem to imply that the well is blown out below the BOP. Otherwise, why wouldn't they try that?
Posted by crosspatch 2010-06-16 13:45||   2010-06-16 13:45|| Front Page Top

#6 I don't know if anyone knows what the second pipe is or where it came from. But it may explain why BP would try to close the upper annular rather then one of the pipe rams. I have read that they needed 16 ppg. mud wt. to balance the well. .052 x 16 x 18000 gives you a btm hole pressure of about 15,000 psi. which is way above the burst pressure of the csg. You would be risking an underground blowout even if you could plug it off at the surface.
Posted by junkirony 2010-06-16 14:08||   2010-06-16 14:08|| Front Page Top

#7 "You would be risking an underground blowout even if you could plug it off at the surface."

Which is what I am starting to suspect happened. The BOP might have activated and then the well blew out below it.
Posted by crosspatch 2010-06-16 14:12||   2010-06-16 14:12|| Front Page Top

#8 You are supposed to be able to remove and replace the BOP, but you would do it with a plug in the well. In principle you could do it flowing, and dump the oil in the ocean (er, like is going on anyway), but I am not sure if the release hardware is functional. They had at one time considered doing that, or adding a new BOP on top of the existing one, but changed their minds. I presume because the casing strings in the shallow part of the well were damaged such that stopping the flow out the top would simply direct it out the sides into the shallow mud, which would then wash out from around the well, allowing the whole thing to fall over and result in unconstrained flow. Sounds from pressure data that they may be nearing unconstrained flow now anyway somehow - much less drop from below the BOP to ambient sea pressure than there used to be - so either the restrictions in the BOP have eroded and are unable to hold as much pressure differential or some of the pressure is bleeding off deeper, out through brokend pipe and into the sands and mud.
Posted by Glenmore 2010-06-16 15:34||   2010-06-16 15:34|| Front Page Top

#9 crosspatch. The BOP weighs about 185 tons and is normally installed and retrieved by the riser which is laying like a pretzel on the ocean floor.

The crane operator testified that the first indication he had that there was a problem was when the gas buster blew up. About the only way that could happen is if the blow out preventers were already closed and functioning and the crew was circulating the gas through the choke line. As the pressure below the blow out preventers approached maximum allowable casing pressure the driller would have been sending more and more gas through the gas buster which caused it to explode. The gas blowing out of the ruptured gas buster was sucked into air intake of the rig engines which caused them to over speed then die. The hydraulics for the BOP'S and the emergency disconnect system is driven by an electric motor which would explain the loss of hydraulics. There are in fact at least three backup systems but someone would have had to be able to get to the main unit to activate them. Even if you could seal of the well off at the ocean floor, that would probably be a very bad idea at this point.
Posted by junkirony 2010-06-16 15:47||   2010-06-16 15:47|| Front Page Top

#10 needed 16 ppg. mud wt. to balance the well

14 ppg. 13,000 psi at the wellhead. Reservoir formation was supposedly less than that - saw 12.5 ppg. Probably less than that now. Hope so or they may not be able to kill this thing until it depletes.
Posted by Glenmore 2010-06-16 19:36||   2010-06-16 19:36|| Front Page Top

#11 I'm sure your right Glenmore. I was pretty sceptical about 16 ppg. mud myself. I would be interested to know where you found your data. I haven't been able to find anything reliable myself.
Posted by junkirony 2010-06-16 22:06||   2010-06-16 22:06|| Front Page Top

00:01 Dash Riprock
00:00 JosephMendiola
23:57 Sgt. D.T.
23:56 JosephMendiola
23:53 Sgt. D.T.
23:50 Dash Riprock
23:48 Dash Riprock
23:42 Frangipani
23:31 Zhang Fei
23:20 Zhang Fei
23:19 Dash Riprock
23:13 Zhang Fei
23:09 Dash Riprock
23:04 Dash Riprock
23:00 Asymmetrical
22:35 Asymmetrical
22:30 JosephMendiola
22:09 DMFD
22:06 junkirony
22:06 DMFD
21:56 M. Murcek
21:51 M. Murcek
21:50 Cornsilk Blondie
21:47 M. Murcek









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