Monday, July 19, 2010

Oil Drum Talking , Dead man walking.

 I went to the Oil Drum to ask a whole boatload of questions a few weeks back. This is what I have gotten in response so far from people who work in the field. I also posted the Banana-Doughnut theory there too lol..

 Questions :

   So I have to say, it was impressive watching them work to put the new flange down, can't says I would have chosen to sew at 5k', but the angular shear on the male end , and the torsion bars on the sides were great. It's really a beautiful application of simple mechanics. I was curious why they opted not to just attach a "stinger" on a 180 balljoint attached to the male end, maybe 2'x1"x1" to guide the initial hook-up, but hey, they got there, that's what counts, it is inevitable that an outcome will happen, A or B, glad it was A. I have gained a massive amount of respect for those of you that work in any of the endless fields that fall under the moniker " Big Oil "...a whole hell of a lot of people fail to see that not everybody who works these industries is out to destroy the universe. In fact, since we are all at the core, very similar, and ultimately desire the same things, I find it interesting that many on other forums, the yelling and explanations of why " it will not succeed ", when SOME solution will satisfy. So kudos to those of you that are working on this. The study of Bayesian probability and public debates has opened my eyes to some very humorous things. I go to places like the Yahoo investors board to observe the monkeys trying to get the banana on the string, then I come here to see what the researchers say. I like standing on this side of the partition much better, monkeys like to fling their own excrement.

    That said, I still have some questions, but they are about kills.

   I understand how Bingham plastics work and I understand how hydrostatic kills work. Please correct me if I am wrong, normally they "soft drill" relief wells, to error on the side of caution when making the initial intersect, to avoid a massive "kick". If the kick is the sum return of the initial wave created by two opposing column faces , and the return is the wave determined by the porosity encountered in the "walls" of a trap, right..? I mean, the energy will go where it can and the rest will choose plan B, of which which is time dependent on the event. So what can't dissipate into porous rock will will effectively go " backwards " towards the first exit, running not walking. Would the aperture of the intersect, or the aperture into the trap be considered a Venturi tube...? I mean, the grade of the enlargement is much less severe, but ultimately the same in principle..? Casing string, small to large, bottom to top, respectively..? What happens if they reach equilibrium and a section pops laterally near the bottom of the gelled column of mud, from any HS stress cracks..? If there is a chance that there is an external void between the casings( there are 2 right ? ), doesn't that mean that stratigraphic pressures are not delivering direct support to the intrinsic strength of the bore. ?
Would the kick from that be massive or inconsequential..? I could see both A or B. I'm picking A, but that's personal. I like to say the best mechanics have no morals.

 response :

What's an HS crack?

While I'm at it, there's nothing empty down there. It either has
1. low porosity and permeability rock (shale),
2. Porous and permeable rock (sand)
3. Mix of the two (shaley sand)
4. Void space (full of mud or hydrocarbons
5. Cement
6. Steel

I believe the relief well is drilling in shale. So, let's say they have mud which puts a 1000 differential pressure across the rock standing between the relief well and the whatever has oil flowing up towards the surface (some say it's the annulus, I say by now it has to be a wormhole running vertically alongside the casing string). Eventually the rock they're drilling ought to crack and they'll just have a bunch of mud squirting from the relief well into the flow conduit alongside the wild well.

Typically, this makes the driller holler and cringe, and the company man starts looking real worried. Now, I suspect they got somebody nearby, say an old guy with a typical oil field name like Wright, or Arceneaux.
This guy will probably tell somebody to speed up the pumps and start putting a lot of mud down the hole.
Meanwhile, the guys sitting in Houston will watch this going on and go say their prayers, because this is when the kill operation has to start. And I sure hope they got themselves hooked up to pump down the kill line if they have to. I would have a boat hooked up to the kill line, and another boat hooked up to the rig just in case.

I don't know if this answered your question. My main concern would be to see them put so much pressure on they'll frac the well, and I haven't seen the well logs, they could have more than one sand feeding in, so this could get kind of complicated.

 Question :

Lol, thanks for the rundown. There's really only 2 types of stratigraphic traps, shear pockets, or fold traps, I think folds are called " Gumbo zones " and are the underside of a salt finger , brine channels help to guide the oil....the surrounding field is always specific to the area, and each different from what I understand, yeah many different rock types and porosity encountered . here's a closeup of an offshore bore return from the initial drill.

HS cracks are stress cracks from reactions of sulfuric acid, seawater can meet rock and form it, or it can be formed in the reservoir.( I believe, otherwise it wouldn't end up coming up the casing ) Sulfide stress cracking it's called. It's a problem for both the outside face of the concrete in the bore that makes contact with the surrounding rock, and the inside of the casing. The analysis being circulated online showing a sweet well does not correlate with the elevated H2S levels in the G.o.M.

But anyway, the plastic zone is where the metal becomes weak at the molecular level and is subject to creep when stress is applied. No big deal normally because surrounding pressure on a bore lining is like squeezing an egg. It strengthens it..until force is applied unevenly, like this >0< . Anyway, my point is that there is always a kick when they intersect, normally gravity takes care of the problem, but lateral failure is not subject to gravity very much at all comparatively. Yeah... eventually the ball falls....

-Also just wanted to add this because I don't know if it is being applied in current drilling tech, but has a very real possibility of utilized. Faraday waves in Non-Newtonian fluids will introduce radical structures. Waves travel through solids with more resistance than liquids...yada yada..Mud is an NN fluid type .It would not increase the density of the mud, per se, but rather create great difficulty for opposing waves to travel through the material, and the wave can travel up the solid casing to follow the mud for some way, all the while imposing it's the structuring takes place at the intersect of face , I'll admit, I do not know, but given the actions of a drilling mud, I would be very interested to hear from some of you, what are your opinions about this. check out this video.

 response :

I wouldn't know about this. The well is pretty new, and there's no reason to have a lot of H2S down there. Therefore stress cracking due to hydrogen isn't something I've given a lot of thought to.
Now, if you try to be less scientific, maybe I would get your concern. For example, are you saying the casing is going to collapse because the mud pressure is going to be a lot higher than the pressure inside the casing? I don't really get your point otherwise.


Ok, sorry man,  sometimes I get long-winded.

   The weight in a vertical fluid column is distributed at the bottom. The bore is a dogleg at around 18k ? The final casing in a well get's bigger as you go from the deposit to the seafloor.? For every larger section of pipe that fluids encounter as they comes around a dogleg of system from lateral to vertical, the pressure gradients change. It's time dependent too. So if you have specific M=pva in this scenario, then you can estimate any "kick" encountered. Anytime fluid enters a larger bore traveling up, there is a slight momentary drop in velocity. My question is that if the bore/casing is damaged, say at something like 16k' , could hydrostatic load pop a weak casing..? Let's say they successfully get equilibrium and 5 minutes later something gives. That whole column above the point of "give" immediately starts to fall downward. When you break the equilibrium , doesn't the mud become fluid again..? Muds gel when they stop moving and settle right..? That's a mighty big hiccup , normally it's either going back into the res, or up to the surface.. And thanks for pointing that about about hydrogen , I appreciate your patience answering my questions, even if ultimately the are the wrong ones.

 .....that was the end of further responses....I am having great difficulty finding answers to my questions. If you guys in Houston are reading this....and I know you are....

                                     ..I know that you might frac' the well....

                                            NN-fluids + Faraday waves.


Anonymous said...

TOD begin every post comment section with "Professor Goose", who describes itself as:

"... Kyle Saunders, associate professor of political science at Colorado State University. "

This is someone who should know enough about conflicts of interests, and unethical behavior with a PhD in Political Science.

Given the money at stake, TOD ought to exercise the highest standards of integrity.

Instead, we find this at the beginning of every comment:

"3. We have gotten a lot of queries whether this bump in traffic is adding costs to keep the site functioning. Truth is, yes, we are incurring added expenses from these events. It is also true that we try not to beg from you very often as we are not the types to bother you with constant queries.

That being said, if you are inclined to help out, your support is always welcome and very much appreciated. To those who have already given, thank you very much.

You can find the donate button in the top left hand corner of the main page."

They beg from money, no questions asked as to source, whether it comes with strings, tainted, etc.

That is even less accountability than politicians.

Anonymous said...

What is the condition / status of Maconda 252?

Anonymous said...

Remember TOD claiming there is no leaks of oil and gas from the seafloor:


"Shortly after the Government’s discovery of the methane and oil leaks was leaked to the media Thad Allen sent a sharply worded letter to BP confirming the statements of the anonymous government official.

""Given the current observations from the test, including the detected seep a distance from the well and undetermined anomalies at the well head, monitoring of the seabed is of paramount importance during the test period.

As a continued condition of the test, you are required to provide as a top priority access and coordination for the monitoring systems, which include seismic and sonar surface ships and subsea ROV and acoustic systems.

When seeps are detected, you are directed to marshal resources, quickly investigate, and report findings to the government in no more than four hours.

I direct you to provide me a written procedure for opening the choke valve as quickly as possible without damaging the well should hydrocarbon seepage near the well head be confirmed.""

The letter from Thad Allen revealed that the multiple statements BP has given to the media over the last few days claiming that there where no signs oil leaking from the sea floor were all outright lies.

Just hours before Thad Allen sent the letter BP gave the following statement during the Kent Well’s technical update which once again denied there was oil leaking from the sea floor."

Where is "Heading Out"?

Heading out to collect his paycheck from BP?