The BP well could be capped tonight

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Ivan Seeking
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A new valve has been installed on top of the failed BOP. Tonight, they will be closing the valves and evaluating the response. I believe that something like 8000 psi on the gauge, means success.
http://www.bp.com/liveassets/bp_internet/globalbp/globalbp_uk_english/incident_response/STAGING/local_assets/html/Hos_ROV2.html

All live feeds
http://www.bp.com/sectionbodycopy.do?categoryId=9034366&contentId=7063636

Edit: In fact, they just now repositioned the camera to center the guage. They must be getting ready.
 
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The ROV's were busy Sunday and Monday. There are about 15 of them in the area now all with cameras.

I still question the idea of loading 160,000 pounds on top of everything else. If the pressure doesn't come up high enough it means there is a leak under the sea floor.

According to news releases the relief well is only five horizontal feet from the main well pipe. They have been drilling through extensive frozen methane. Hot oil passing through frozen methane doesn't sound good.
 
One big concern of the cap is whether or not the pressure may crack or break a pipe elsewhere along the line. The cap is fantastic, and I hope beyond anything I can articulate that it works well until they the relief line over.

There's also the concern of why they didn't use this thing months ago. All of the parts for the cap were readily available and the little underwater mabob working on it was available too. But I guess we'll have to leave WTF is up with BP with that for another day and cheer anything that will stop the incessant puking of toxins into the world's water supply and ocean world.
 
GeorginaS said:
One big concern of the cap is whether or not the pressure may crack or break a pipe elsewhere along the line.
Unless there is the expectation of another component damaged somewhere, I don't know why this would be a concern.
There's also the concern of why they didn't use this thing months ago. All of the parts for the cap were readily available and the little underwater mabob working on it was available too.
I wondered that as well. We don't know a whole lot about how they went about their contingency operations. When you think about what they've done over the last 3 months, there really were only about a half a dozen major efforts made to stop the leak. I wonder if they immediately started pursuing all of them in parallel or attacked them one at a time - I'm sure the cap took several weeks to actually design and construct. Anyway, though, a wellhead cap seems like an obvious best fix compared to things like hanging a big funnel above a broken pipe!
 
According to this story they are on hold with the pressure testing.

(CBS/AP) Updated at 11:53 p.m. ET

A pivotal moment in the Gulf oil crisis hit an unexpected snag Tuesday evening when officials announced they needed more time before they could begin choking off the geyser of crude at the bottom of the sea.

BP and federal officials did not say what prompted the decision or when the testing would begin on a new, tighter-fitting cap it had just installed on the blown-out well. The oil giant had been scheduled to start slowly shutting off valves on the 75-ton cap, aiming to stop the flow of oil for the first time in three months.

http://www.cbsnews.com/stories/2010/07/13/national/main6675968.shtml
 
russ_watters said:
Unless there is the expectation of another component damaged somewhere, I don't know why this would be a concern.

There is [or was] no way to know if there is additional damage below the bop. One of the big concerns is that well casing might be damaged. The potential for damage exists due to the blowout.

I wondered that as well. We don't know a whole lot about how they went about their contingency operations. When you think about what they've done over the last 3 months, there really were only about a half a dozen major efforts made to stop the leak. I wonder if they immediately started pursuing all of them in parallel or attacked them one at a time - I'm sure the cap took several weeks to actually design and construct. Anyway, though, a wellhead cap seems like an obvious best fix compared to things like hanging a big funnel above a broken pipe!

Allegedly, this was started almost right away. My best take on this is that it has never been done before, so a lot of engineering had to be done first. It was reported somewhere along the line that Chu himself was working on this one.

I remember that early on, this approach was considered very risky due to potential damage to the casing. If they cause the casing to blow out of the hole, which [in some sense] is possible, there is no more to be done except the bottom kill. So this may have been treated as a last resort due to risk. In know they have been doing various analyses of the well and the surrounding material, so that may play a role. They now seem to be reasonably confident that the well will hold under pressure.
 
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Ivan Seeking said:
There is [or was] no way to know if there is additional damage below the bop. One of the big concerns is that well casing might be damaged. The potential for damage exists due to the blowout.
I'm not following - what could the blowout do to the well below the BoP? It isn't like the well saw abnormal pressure or anything - all of the damage should have been after the BOP (besides whatever happened when it tried and failed to close). A blowout/gusher is just a well without a cap on it.
 
Was there not initially an explosion and a fire? And could that not have damaged more of the pipe than just the part that connected the main pipe to the rig? And wasn't that an issue when they tried the top kill procedure, that not only was the oil still blowing out around that plug but began leaking from a cracked pipe elsewhere?

That's what I've heard. Could be entirely wrong, though.
 
russ_watters said:
I'm not following - what could the blowout do to the well below the BoP? It isn't like the well saw abnormal pressure or anything - all of the damage should have been after the BOP (besides whatever happened when it tried and failed to close). A blowout/gusher is just a well without a cap on it.

I know that is one of their concerns [according to Thad Allen and others]. But whether the potential for damage results from the blowout, or potentially was the cause of the blowout, I'm not sure. There was a reason for the blowout, and I don't know that the well never experienced abnormal pressure.

Where do you get your information? How do you know that the well never experienced any unusual pressure or abnormal conditions that could cause damage?

The last report indicates that they stopped to do some additional analysis. That doesn't sound good.
 
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Ivan Seeking said:
I know that is one of their concerns [according to Thad Allen and others]. But whether the potential for damage results from the blowout, or potentially was the cause of the blowout, I'm not sure. There was a reason for the blowout, and I don't know that the well never experienced abnormal pressure.

Where do you get your information? How do you know that the well never experienced any unusual pressure or abnormal conditions that could cause damage?

The last report indicates that they stopped to do some additional analysis. That doesn't sound good.

From the CBS link above:

A series of methodical, preliminary steps were completed before progress stalled. Engineers spent hours on a seismic survey, creating a map of the rock under the sea floor to spot potential dangers, like gas pockets. It also provides a baseline to compare with later surveys during and after the test to see if the pressure on the well is causing underground problems.

An unstable area around the wellbore could create bigger problems if the leak continued elsewhere in the well after the cap valves were shut, experts said.

I am surprised that they didn't already have a seismological map of the formations below the well. That is how they find the oil.
 
If the cap works, will all of these SES people go back to being their boring selves again?
 
Woohoo! In the last five minutes, they started shutting down the flow and raising the pressure in the system. As of right now, the flow from the main pipe has stopped! Apparently the pressure is holding. They will be testing for some time. There is still some flow from other outlets, and main flow might start again, but so far, so good. I'm hearing that they hit the 8000 psi mark with no problem.

Thad Allen had just finished a news conference and given the go ahead, about an hour ago. A 24 hour delay had been imposed by the government, for review, to help ensure that they wouldn't cause a casing failure, so the test never did start yesterday.

Edit: It doesn't make sense that it would be up to 8kpsi already. That must have been a misstatement.
 
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GeorginaS said:
Was there not initially an explosion and a fire? And could that not have damaged more of the pipe than just the part that connected the main pipe to the rig?
There was an initial explosion and fire, but that was at the surface, 3/4 of a mile above the wellhead on the floor of the Gulf. The explosion and fire did not touch nor could have had any direct impact on the wellhead.
And wasn't that an issue when they tried the top kill procedure, that not only was the oil still blowing out around that plug but began leaking from a cracked pipe elsewhere?
Yes, but all of that piping has now been removed and the cap right on top of the wellhead, above the blowout preventer.

The blowout preventer and where it connects to the wellhead are the only components that have much chance of being damaged - they were probably subjected to forces they weren't designed for when the piping riser fell to the sea floor around them. Below that, it's just a pipe imbedded in rock for 6 miles - I don't see how any of that could have been damaged.
 
russ_watters said:
Below that, it's just a pipe imbedded in rock for 6 miles - I don't see how any of that could have been damaged.
The final certification of the concrete installed by Halliburton was not performed. The company contracted to do that evacuated its employees from the rig after the rig's operators refused to honor a stop-work order. There may be some concern that there are gaps or weak concrete between the drill-pipe and the surrounding rock, which could allow the pipe to blow out and rupture, allowing oil to emerge from around the pipe. We may never get all the details surrounding this incident, but there seems to be some uncertainty and some caution surrounding the application and closing of this new cap.
 
Ivan Seeking said:
I know that is one of their concerns [according to Thad Allen and others].
I see that in several stories now (hadn't read any yet this morning when I posted before). Perhaps it is just an overabundance of caution (better than an underabundance, to be sure), but I just don't see how it is possible for there to be damage below the wellhead and they aren't specific about what they are looking for or why.
But whether the potential for damage results from the blowout, or potentially was the cause of the blowout, I'm not sure. There was a reason for the blowout, and I don't know that the well never experienced abnormal pressure.
A blowout in and of itself isn't really that violent of an event. It used to be par for the course in drilling until it was decided that the loss of oil, pollution and risk of an explosion was too high to keep doing drilling that way.

From what we've been told so far, it seems relatively clear that the cause of the blowout was the removal of the heavy drilling mud before the concrete lower riser caps cured, which pressurized the entire riser before it was ready to take pressure. Then the blowout preventer failed to contain/stop the blowout.
Where do you get your information? How do you know that the well never experienced any unusual pressure or abnormal conditions that could cause damage?
:confused: :confused: There's a thousand posts in a half dozen threads in PF on the subject. I didn't think the general cause of the accident was much in doubt anymore.

Most of the keys were laid bare in the 60 minutes interview a couple of months ago. http://www.cbsnews.com/stories/2010/05/16/60minutes/main6490197.shtml
 
turbo-1 said:
The final certification of the concrete installed by Halliburton was not performed. The company contracted to do that evacuated its employees from the rig after the rig's operators refused to honor a stop-work order.
Yes, and in fact, the last plug wasn't even fully set before the accident. That's in the riser and it appears the blowout broke through the caps. But that is very unlikely to damage the riser itself.
There may be some concern that there are gaps or weak concrete between the drill-pipe and the surrounding rock, which could allow the pipe to blow out and rupture, allowing oil to emerge from around the pipe.
It was my understanding that the caps are inside the drill pipe (riser), between it and the oil extraction pipe.
 
russ_watters said:
From what we've been told so far, it seems relatively clear that the cause of the blowout was the removal of the heavy drilling mud before the concrete lower riser caps cured, which pressurized the entire riser before it was ready to take pressure. Then the blowout preventer failed to contain/stop the blowout. :confused: :confused: There's a thousand posts in a half dozen threads in PF on the subject. I didn't think the general cause of the accident was much in doubt anymore.

Most of the keys were laid bare in the 60 minutes interview a couple of months ago. http://www.cbsnews.com/stories/2010/05/16/60minutes/main6490197.shtml

You seemed to suggest this is not a problem, or that it contradicts something you have seen, but it [a casing failure] has been at the top of the list of concerns from day one. An abundance of caution? Perhaps. If the casing fails, nothing more could be done less the bottom kill. And from what I understand, there are situations where even that would be ineffective in stopping a leak.

The test had to be stopped last night due to a leak in the choke line. But about 45 minutes ago, they started again.
 
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I would add that I don't think anyone knows for a fact what happened yet. It may all seem to make sense based on certain criteria, but a 60 minutes reports hardly qualifies as a failure analysis.
 
BP just announced that the flow of oil has been completely stopped!

It is a bit confusing to make sense of the testing procedure. They may have to allow additional flow at times, but at the moment no oil is flowing. As near as I can tell, as long as the pressure holds, the source of this nightmare is finally under control.
 
ivan seeking said:
bp just announced that the flow of oil has been completely stopped!

whoohoooo!
 
Note that the gauges are for ROVs and not for the well. Only transducers are used to monitor the well pressure.

BP just tweeted CNN to clarify that point! :smile:

I have to admit that I was a little worried to see the one gauge sitting at 3kpsi. Whewww.
 
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Uh oh, Thad Allen is now calling this a temporary means of shutting down the well in the event of a hurricane, in which case the ships would be forced to leave. Apparently they are now planning to go back to capture. But, it was also noted early on that capture is now practical as they have a clean connection.

This is definitely a change in the language, so I can't help but suspect that they see a problem. But they still think they can capture 100% of the oil now. They are prepared to receive 80,000 barrels a day.
 
Ivan Seeking said:
BP just announced that the flow of oil has been completely stopped!
:biggrin:

[PLAIN]http://www.thedpn.com/b/images/smilies/icon_party.gif GOOD NEWS! I was planning to go look at the spill tomorrow.
 
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Office_Shredder said:
That was your biggest concern?

Yes.
 
KalamMekhar said:
Yes.
I have a friend who co-owns and operates the largest flash-freezing plant for processing shrimp in Mississippi. His business is ruined, his former employees are unemployed, his suppliers and the shrimpers who they buy from are losing their boats, homes, berths, docks, businesses, etc. The people that supply essential services to all these now-unemployed people are also hurting badly, and some may never be able to jump the hurdle of BP's promise of paying claims for "verifiable losses". You worry about the lost oil? 10 years from now, the lost oil will be forgotten and the lost livelihoods and habitat may still be with us.