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oil leak gulf of mexico 5

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CH5OH

Petroleum
Oct 4, 2009
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just some open topic...
being an engineer, how would you go about to seal off a leaking well @ 1500m depth.
try to get Redair to get into a divesuit, convincing him the depth is kinda exagerated ?
Any bright idea's ?
 
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Did you see the one about using cheap casing?
a
To help with the stress, BP has laid on massage therapists in an alcove in the command center, with two massage chairs.
"When you're working people as hard as we are, you have to provide some stress relief," Kent Wells, BP senior vice president, told Reuters on Monday.

They want to turn off the cameras and not talk about real numbers, the supposed 700M they've already spent trying to fix it, because they don't want anyone racing to the real 50 Billion in cleanup and legal costs they could be approaching right now, today.

Today was the first time I heard some newscaster say BP could be looking at "10s of billions" in costs. Well .. it's about time somebody (besides me) started doing the math. If the leak has always been 20 KBOPD * 35 days * $ 32,500/BBL * 1.9, today they're looking at a $43 Billion (based on Valdez cost/BBL adjusted for inflation and BBLS spilled, but not for economic value of area affected). Right on target to hit my projected 100 B if it goes until the relief well gets drilled, but they may be broke by then.


"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO, BP

**********************
"Being GREEN isn't easy" ..Kermit

 
A friens of mine worked suraface wells for years in Alberta. He is astonished that the work continued without fixing the annular bag in the BOP as soon as it was damaged. He is further astonished that normal work continued after it was known that the BOP had a hydraulic leak and low hydraulic pressure.
Although the final trigger to the blowout may have been the controversial command to replace the mud with sea water, The known issues with the BOP took away their safety backups.
Many accidents are the result of more than one coincidental issues. Often three or more coincidental issues.
1> Had the annular bag been repaired on the BOP it had a good chance of benignly stopping the flow when the cementing crew first discovered rising pressures. The driller apparently activated the annular device in time but it had been destroyed a month previously and not replaced.
2> Apparently it was known that the BOP was leaking hydraulic fluid, and operating pressure was low. Had that issue been addressed it is likely that the BOP would have operated in time to save the rig and possibly the lives.
3> The decision to proceed with the removal of the mud despite ambiguous pressure test results may have been recoverable in the absence at least one of the other factors.
I remember being in an arbitration hearing and hearing a PE describe his theory of an accident. After the workers brole the control block, it fell UP into the main contacts and initiated the fault.
Everyone was so aghast at his disregard for basic physics that the defense attorney did not even ask him to reconcile his theory with the law of gravity. His position prevailed.
I am sure that BP's lawyers will be able to suppress most of the facts on one pretext or another.
I wish I wasn't so cynical, but with corporate survival at stake and billions of dollars available for lawyers, I fear that the next casualties in this disaster will be logic, truth and justice.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
waross,
Totally agree, if only some one in authority would have asked the proverbial question "how come".

A very interesting read. The thing that bothers me is this was a drill ship. That means it was a ship under maritime regulations and on a ship is in charge if he is alive and that is the Captain.


The total mud pumped was announced as 30,000 barrels.

waross
Also agreed that science and law or lawyers don't go together. i had a friend who was sitting at a traffic light and was hit by a county dump truck. The attorney was using diagrams and physics to prove that the county truck hit the car because he didn't go on the light. About 30 seconds into his spiel my big boss who was on the jury called "BS" on him. For this he thrown off the jury and fined for contempt of court. After he was removed the judge allowed the lawyer to go and the county driver got off and my buddy was charged with impeding traffic. My boss had a PhD in Engineering Physics and Chemical Engineering.
 
waross (and, I know nothing about drill rigs)...

"He is astonished that the work continued without fixing the annular bag in the BOP as soon as it was damaged."

Would whoever was doing the work know the function of the annular bag and if it had failed, would he not require some kind of permission to continue without it?

In a similar fashion, would he know what might be the likely cause of the hydraulic leak? or the low hydraulic pressure?

"Although the final trigger to the blowout may have been the controversial command to replace the mud with sea water,"

Why would this be done? and with the pressures involved what would be the difference between using drilling mud and sea water. Is the drilling mud a 'swelling' bentonite type of material?

"The driller apparently activated the annular device in time but it had been destroyed a month previously and not replaced."

I would assume that the driller did not know that the annular device was inoperable, else he wouldn't have tried to activate it. Is this correct?

"I wish I wasn't so cynical, but with corporate survival at stake and billions of dollars available for lawyers, I fear that the next casualties in this disaster will be logic, truth and justice."

... my earlier comments...

Was BP actually looking after the work? or had they sub-contracted to others? Do they have an involvement, other than owning the well?

Dik
 
"Although the final trigger to the blowout may have been the controversial command to replace the mud with sea water,"

As I'm sure you've found out by now, the "mud" is a complex chemical formulation of clay, varying brine content, gels, minerals, of varying ph and chemical compatability with the near surface environment, the geologic formation and even with the crude. Properties of the mud can vary widely depending on if it is being circulated or if circulation has stopped. If circulation is stopped, shear stresses may change and make it very difficult to restart, salt crystals can form, hydrates can form and flow can become blocked. It wouldn't be too surprizing to find out that salt crystals or hydrate formation was responsible for initial plugging, which may have caused some confusion about the pressure readings of the well tests. Its also slick and dirty, so its usually removed before final cementing to get a good bonding surface for the cement setup. That's probably why it was being removed and replaced with seawater.

I would imagine the drill boss believed the BOP and all equipment was in working order.

The company rep always, always, always has the last word. Did I mention "always". This next article suggests that his last word came after a "skirmish" with TransOcean personnal, which to me would also indicate that there might have been considerable emotional involvement clouding that judgement rather than being the result of pure logic. I'm sure you know I don't like to spectulate (joke), but stranger things have happened, right?

"Skirmish"

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO, BP

**********************
"Being GREEN isn't easy" ..Kermit

 
Here is the 60 Minutes interview with Mike Williams from the DWH. It gives a little better time line and the reason for the loss of power, but mainly the loss of the annular valve.


The government keeps referring to the two relief wells being drilled when for several days there has been only one well being drilled. BP stated yesterday that the second drill ship had even move off station.
 
The flow capacity is just a little tiny bit more than
the maximum of what I calculated above according to this article,

80 bbls/m
3360 bbls/h
80640 bbls/d




"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO, BP

**********************
"Being GREEN isn't easy" ..Kermit

 
Has anybody seen a copy of the flowrate calculations done by the US gov Flow Rate Group?

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO, BP

**********************
"Being GREEN isn't easy" ..Kermit

 
I've been watching the cut progress on the live feed.

It's clearly getting hard to maneuver the camera sub because of the flow from the cut.

As of now, it appears they've gotten what I think is a wire saw stuck in the kerf, possibly because of the claw pulling up on the bent-over portion of the riser pipe and closing the kerf, just like my Dad yelled at me for when I was 'helping' him saw lumber.



Mike Halloran
Pembroke Pines, FL, USA
 
{b]MikeHalloran[/b],

If your observation is correct, that was one of the main problems considered when they chose thee diamond wire saw.
There are other considerations to look at, like the presure jet is taking some of the contact pressure off the wire. Another is that the drill pipe inside the drilling riser is vibrating. This would be almost like trying to cut a tube with free round solid rod inside rolling with the saw.

For all:

 
Right now the live feed is showing plankton or something.

From 4AM EDT to a while ago, it looked like they had stopped the wire saw, and maybe backed it out of the kerf, and had something on the end of a shiny arm extending from the camera sub into the area of the wire saw's guard in line with the kerf. I couldn't figure out if it was an impact wrench on a bolt, or a circular saw above the bolt head. It didn't translate for all the time I watched it.



Mike Halloran
Pembroke Pines, FL, USA
 
DOUBLE WALL SEA ANCHOR>> Forgive me if this has already been talked about, but I feel obligated to get this idea out for scrutiny. I watched on Discover channel, just a couple of weeks before this disaster, about how floating derricks of this type were stabilized from the ocean floor. If I remember correctly they called them vacuum anchors. Which were dropped into the ocean from the derrick, I assume imbedding themselves in the ocean floor like a lawn dart and then a vacuum was pulled, thereby using the advantage of ocean depths to push the anchors with mooring lines into the sea bed.

I am wondering if a double wall vacuum sea anchor could be built. Basically a large diameter pipe with a smaller pipe inside which the diameter of the inner cylinder would be large enough to clear the largest well casing and BOP. The top of the pipe would be sealed with a plate. Above the center pipe chamber would be located a "working" BOP would be installed in the open position. A "vacuum" would be pulled on the outer ring of surface area between the inside of the largest cylinder and outside of the inner cylinder. Calculations assuming a certain pressure on the inner area could be counter acted with the ocean pressue on the outer area. This area would be sized to counteract the pressure in the well to hold this device in place after the BOP valve is shut. Also some addition friction could be utilized from the soil surrounding the imbedded cylinder.

 
Her is the Wach's diamond Wire saw being used. One can not wee it clear enough it appears to have been slightly modified from the brochure.



TGordon15,
This ship has no anchors as it has a dynamic positioning system. I don't know to what sea state will hold it's position, but it is pretty high.
Checkout the last two picture links in my 1 June 10 21:27 post, it is holding station at this time.
 
Holding position and working wave height are usually entirely different criteria. Even though there is no wave action at the bottom, you still might have to recover or deploy tools from a pitching deck and through the surface water waves, so they can only work up to a wave height and wind velocity that would be significantly smaller than what holding position limits would allow...unless of course they increased their risk tolerance a corresponding amount.

"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO, BP

**********************
"Being GREEN isn't easy" ..Kermit

 
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