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BP Prepares Complex "Top Kill" Bid To Plug Well
shmG excerpts from the International Business Times: "Government and BP officials are hopeful after extensive preparations, but are not guaranteeing that a complex attempt early this week to cap an uncontrolled underwater oil spill from a well in the Gulf of Mexico will be successful. The so-called 'top kill' procedure that oil major BP is tentatively scheduled to attempt on Tuesday involves plugging up the well by pumping thick 'drilling mud' and cement into it. While it had been attempted on above-ground wells, it has never been tried at the depths involved with this spill, nearly 5,000 feet below the surface."
They will and are already paying.
As they should....
Veni, Vidi, Velcro!
He's talking about the 5 nukes the Russians used, 4 of which succeeded. Of course the Russian oil wells were surrounded by hard, brittle rock, while the leak in the Gulf is surrounded by mud. Different environment leads to different results.
http://www.timesonline.co.uk/tol/news/world/us_and_americas/article7129225.ece
"According to a survivor’s account... blowout preventer...was punctured in the weeks before the blast but nothing was done to fix it.
"a crewman accidentally nudged a joystick, which sent 15ft of the oil pipe through the closed device"
"Mr Williams added that a crewman “discovered chunks of rubber in the drilling fluid”. He thought that it was important enough to bring them into the driller shack. “I recall asking the supervisor if this was out of the ordinary. And he says, ‘Oh, it’s no big deal’
"two control pods that operate the blowout preventer had lost some of its function weeks before the explosion, and the batteries on the device were weak. With the schedule slipping, Mr Williams said that a BP manager ordered a quicker pace. The faster drilling had caused the bottom of the well to split open, swallowing tools. “There’s always pressure [on the crew], but yes, the pressure was increased,” he said. "
So what do you do? Pretty much what they did - cotinue and hope for the best.
Wrong. You stop drilling and eat the $10 million you've dropped on the well so far. If that's not acceptable to you, don't drill off my damn coast.
It should be illegal to say that freedom of speech should be limited.
Real explosives don't need ambient oxygen. Internal break down of (usually Nitrogen) bonds releases the energy, not rapid oxidation. A few exotic chemistrys exist, such as getting a normally inert noble gas to combine with a reactive gas (i.e. Xenon Trifloride) to store similar levels of energy, but mostly it's Nitrogen. C-4 isn't really the name of an explosive, but Composition 4 is about 90% RDX, which is the high explosive part (also called cyclonite). The other 9 to 10 % is the plasticizer that makes it putty like. No, C-4 does not require outside Oxygen, although it's probably not the stuff to use here. I'm sure the US Navy has some data on what explosives stay safe under very high seawater pressures and still react quickly, hopefully someone will ask them as needed.
Who is John Cabal?
So what do you do? Pretty much what they did - cotinue and hope for the best.
Umm, I have to say I work on all surface stacks, but if I was the company man in charge - and yes that is my current job for another major (... okay, fine, company person) - we'd shut the pipe rams, bleed the pressure above them, and fix the annular. Changing out an annular preventer on a surface stack is a relatively routine procedure. Close the pipe rams, bleed the pressure off, unbolt the top, remove the annular, cut a new one in half to go around the pipe, replace it, retighten the bolts, retest, and get on with it. I find it hard to believe that they don't have a way to replace the annular with an ROV. The blowout preventer is not a singular piece of equipment. The annular, the pipe rams, and the blinds can all be functioned and replaced separately. If your blinds are messed up, you have to get more complicated and start setting plugs, but anything above that you should be able to change fairly easily.
There's a few docs online from one of the oil field "auditors" (the ones that value reserves and help measure risk, advise on investing and so are familiar with the science) and it looks to me from those reports that there's a good chance that everyone knows why the well blew out. The BOPs failing is a separate subject. A BOP are like airbags in a car. They help mitigate the damage, and the BOPs didn't. What it looks like is that the cement job failed, and the design of the pipe in the hole didn't allow for a casing hanger. Start with this document: http://www.tudorpickering.com/pdfs/tph.well.slides.pdf Look at Schematic #3. You'll see the 7" x 9 7/8" (tapered) casing is run to surface, through the 9 7/8" lnr (not run to surface) There is a space and the possibility that the blowout happened from poor cement across the oil/gas formation and then between the 7" and 9 7/8" liner. It would have a free run all the way up to the base of the BOP. This also implies the 7" x 9 7/8" casing is still viable and still has cement plugs in place. If all true, then it also means that this well would have blown out with heavy mud in the casing. For the heavy mud to get down in a large 9 7/8" space with the oil flowing is one thing, as it's being engineered for. For that same heavy mud to get into a much smaller space , the space between the 9 7/8" pipe and the 16" casing (again, look at the red line/arrows in the diagram) with the oil and gas "jetting out" is going to be much tougher. What may happen is the heavy mud goes in, and gets rejected out, and _then_ the call goes out to put in the junk, stopping up the flow partially, and then trying more heavy mud. They've got plenty of mud, so they say, so they'll try this to see what happens.