http://online.wsj.com/article/SB1000...5024.html?mod=
The link to part I is on the left side of the page. This an interesting excerpt:
I know exactly what they are talking about. I've drilled plenty of oil wells. Those things cost about $100 and take maybe a minute to install. BP was spending a million dollars a day for that rig yet, they cut a crucial corner that saved them...$2000 and about 15 minutes of time. This is the same guy that told them to switch from drilling mud to brine water all the while the Transocean people were arguing with him all the way.Halliburton, the cementing contractor, advised BP to install numerous devices to make sure the pipe was centered in the well before pumping cement, according to Halliburton do ents, provided to congressional investigators and seen by the Journal. Otherwise, the cement might develop small channels that gas could squeeze through.
In an April 18 report to BP, Halliburton warned that if BP didn't use more centering devices, the well would likely have "a SEVERE gas flow problem." Still, BP decided to install fewer of the devices than Halliburton recommended—six instead of 21.
I hope they throw this guy in jail. He made so many hair brained decisions it's unbelievable. Basically he didn't listen to Transocean or Halliburton when they were telling him, 'Don't do that.' But I blame Transocean too. They should have told him, 'no way you're doing that on this rig'.
What a tragedy. And avoidable, as most tragedies are.
Just as with Wall St where tons of evidence pointed to wide-spread, systematic fraud and theft, which continue, with no accountability or punishment, BP will escape with a wrist slap, because corps own Congress and regulatory functions of the Exec.
America is ed
Question.
How would the lack of pipe centering and poor concrete flow cause the problem that occurred? What am I missing?
The newest thing I have read of interest is that the manufacturer of... help me out... I forget the device name... is not being looked at because it failed to shut off the oil flow.
That's explained in the article. Hard to explain without being able to draw a diagram.
The manufacturer of the blow out preventer was not responsible for it's maintenance. On the drillship I was on there were people who carried the le of 'sub-sea engineer' that were charged with the maintenance of the BHP and riser system. Just like an American Airlines mechanic is charged with maintaining a jet they buy from Boeing.
The problem was, they didn't have enough fluid weight to hold the pressure. Bottom Hole Pressure is calculated as depth x weight of fluid x .052. Seawater weighs about 10 lbs gallon depending on salinity. At 16,000 feet using salt water, there was about 8000 lbs of fluid weight trying to hold back the gas pressure. So we know that the bottom hole pressure that that well produced, was in excess of 8000lbs.
Brother, that's a of a well. No way a hydril to shut in casing can hold that. Most land rigs I worked on, a hydril was rated to 3000 lbs. Offshore a little beefier but I don't know if they were THAT much beefier. A blow out preventer has 'stacks' the each are set up to shut in specific diameter pipe or completely close it. The weakest link is the hydril, for large diamater pipe, which is ...casing. I don't know of a hydril rated to 10,000 lbs. I'm sure they make 'em, but you're getting awfully close to maxxing a BHP out with 8000 lbs of gas pressure. I don't even know if they make a BHP to hold back in excess of 10,000lbs pressure.
It was a of a well. They got themselves a tiger by the tail down there.
Man, I hope they get that thing under control but it's a beast. That well is a ing monster.
Since I double posted here I'll edit/add.
I kinda see where BP made their mistake and what the arguement was about between BP and Transocean. BP had Transocean go from drilling mud to salt water to run casing. Not an outrageous decision considering the depth. They had 8000 lbs of bottom hole pressure with salt water. I've seen rigs burn down to the ground when they lost control of 2500 lbs of gas pressure.
What you do, when you drill into a gas pocket with high pressure is you shut it in, then, you start increasing you fluid weight and hold 'back pressure' on the circulation and circulate the gas bubble out. Gas expands as it has less pressure against it. That is, as it rises up through the hole to the surface, encountering less pressure/resistance, it expands. The trick is, to circulate it out, without creating a new 'bubble'. Once you have it circulated out, AND you have increased the weight of your fluid, usually using barite, then you can safely go about your business. You can continue, if you chose and feel like you have it under control. That is called drilling 'out of balance'. You get no returns. You put more fluid in the hole, than you get back. A method not recommended unless you're in an area you know there are no surpises. A known field. I assure you, at 5000 feet of water depth, it wasn't a known field.
What was happening is it was 'knocking the bottom out' and they would lose circulation and their fluid. They were in a bind. It doesn't surprise me they lost control of it.
But ...but...if you don't have heavy enough fluid in the hole, and no drillpipe in the hole, and you've just cemented and have NO WAY of ciruclating fluid and adding heavier drilling mud, you've effectively been caught with your pants at your ankles. You couldn't even circulate the casing. You just cemented it in.
When that well came in, in the situation they were in, all they could do really, is abandon ship and get the off of it. It was done, there was nothing they could do.
Last edited by word; 06-01-2010 at 07:31 PM.
I do understand most of the descriptions in the article. What I don't understand is why the cutting off of the pipe failed, or why the lack of centering could have made the difference. Some centering was achieved. I understand that the number of centering devices was acceptable as minimum. Does this mean Halliburton didn't trust their own concrete pouring skills?
I agree that safety was ignored. We have layers of safety in case one or more layer fails. It seems the critical mistake made by BP was trying to save the time and cost of the "mud."
It had nothing to do with Halliburtons skills. Read the post above yours that I added to the 'double post'. It had nothing to do with Halliburton. That's just goofball lefty CHENEY halliburton crap. Halliburton has cemented nearly every oil well drilled on this planet. Several hundred thousand. Their expertise is without question and it's not even that complicated of a procedure. It's fluid dynamics and basically, pretty simple math. The Halliburton 'red book' is the bible in the oil field. It has the formulas for every procedure there is.
Last edited by word; 06-01-2010 at 07:35 PM.
OK, if the number of spacers were industry standard acceptable minimums, who makes that decision? Is it in regulation, or an unofficial rule?
Now I agree the fluid dynamics are simple, but I know most people don't understand what the densities of the oil, sand, water etc. do. The absolute pressures are tremendous, and the differential pressures are extreme as well.
In the end, with the engineering challenges know, I don't understand how such materials and procedures can be so lax. OK, we had a series of human error decisions which appears to be the reason for all this. Still, why did the cutoff hydraulics fail. All in all, this is an item that simply cannot be under engineered. It simply must work if needed.
Why aren't piloted check valved used on all the pipes?
What about not circulating the "mud" through the entire pipe system at least once? Wouldn't this situation have been detected?
"I don't understand how such materials and procedures can be so lax"
because you're stupid.
BP and corps in general don't GAF about the safety, welfare of their employees or products.
when was 2k alot of money to these wankers who made a killing when petrol prices were going through the roof
No. This goes past normal corporate decisions. I can understand some procedures being ignored. Not ones that have such possible repercussions. I will agree that there is probably criminal violations involved. If regulations allowed this to happen, there definitely needs to be some changes.
As I learn more about this incident, I want both the maker of the hydraulic "pincher" devise and BP held accountable.
"regulations allowed this to happen, there definitely needs to be some changes."
regulations? We don't need no stinking regulations, when we got oilco lobbyists plying MMS employees (who are ex and future oilco employees and lobbyists) with s and cocaine!
I have no proof, but I'm sure head's Secret National Energy Policy's "tone", if not his specific words were that oilcos could forget about regulations and regulators and drill baby drill, onshore, deepwater, all over Alaska and anywhere, along with "we're invading Iraq for the oil. Study your Iraq oil field maps"
"changes"? what changes?
MORE regulations and good-faith/badass regulators? We can't do that, there's a (Repug/conservative) deficit, doncha know?
You do do that. Here's how it works. Once you have reached the depth your are going to run casing you circulate fluid with drill pipe in the hole. You can circulate it as many times as necessary but generally 2 full circulations. You determine you are ready to run casing when you get no cuttings back in circulation. You have a 'clean hole'. Then you pull your drillpipe and run the casing. Once the casing is run, it has a plug at the bottom of it that is open. You start pumping cement. When you have pumped enough cement to fill the hole outside of the casing you follow it by pumping drilling mud or in this case, water so your casing isn't filled with cement. Behind this, at the right time of course, you put in a plastic ball that plugs the 'plug' at the bottom of the casing, preventing the heavier cement, from balancing out and oozing up into the casing. Fluid dynamics again. Then you wait for the cement to dry.
This is when this well blew out. There is no worst time for this to happen.
Compound that by the fact they were having lost circulation problems it is very possible the cement job just lost the fluid and the gas came up around the backside of the casing, not throught he inside of the casing. That was plugged. In fact, that is what happened.
It's a worst case scenario. Absolutely, the worst case scenario.
At the time I was working in the industry, it was up to the oil company. It's their money. They have the say and the last word depending on the contract. If the well is being drilled on a contract then the drilling company ( transocean ) would have the final word. This well was being drilled on a per diem. That gives BP the final word.
So is something I read wrong, that they didn't even do one full circulation before using the sea water?
The free market will fix this.
Problem... Solved.
Clearly they circulated the hole enough because they were able to run casing. Circulating before running casing has nothing to do with the issue of the well blowing out on them. If the well had been coming in before they wouldn't have run casing . If you're getting gas kicks, you want your drillpipe in the hole, for sure. They thought they had it stabilized...) Curculating with water you'll need more circ time, as water doesn't have the same viscosity as drilling mud and isn't able to carry out cuttings as well as a gel based mud.
That's moot anyway. They ran the casing with no problem. The problem was the cement job.
I heard tonight the argument was about how they were going to leave the hole ( that is what condition...drilling mud or water ) before they pulled the BOP and riser and the Deepwater Horizon moved on to another job. There is no question, at all, that when that well came in, there was nothing, absolutely nothing they could do. Well I take that back. They could have started tripping their drillpipe back in the hole but generally, when you are running production casing, you come out with drill pipe 'laying down' and break off each joint and lay it down, rather than stand it in the derrick in triple joints.
All guess work on my part as to what they were doing and where they were in the process. All I know is they were done drilling and had run production casing and done the cement job on the casing.
Here is what is interesting. Before you run production casing, after you've finished a well, you always log it. That is what Schlumberger does. They are a wireline outfit that does oil well logging. I believe it is federal law they have to do this. That process takes anywhere from 12 hours to a couple of days, depending on how many tests they run and how deep you are. But to do that, you have no drill pipe or production casing in the hole. They log it from the intermediate casing ...down. So they had a stable well at least 24 and problably closer to 48 or 72 hours. So clearly, the cement job affected the well. That's when it came in. The only variable would be the weight of the fluid. There are three things you can control in drilling mud. Acidity/Alkalinity, viscosity, and weight. That's it.
Review this article bearing in mind that seawater is about 10 lbs per gallon:
http://www.oilvoice.com/n/Halliburto...d500abf59.aspx
I think that explains it right there although it does say further down that Halliburton had developed a 'glass slurry' 'Using Tuned Light ultra-light weight cement' that weighed 7ppg ( which is lighter than fresh water which I believe is about 7.4ppg going off of memory ).'Cement slurries are often designed with a lead and tail,' explains Kulakofsky. 'Typically a lead slurry will be around 12.5 pounds per gallon (ppg), with a 16ppg tail. The 12.5ppg lead provides the required height of fill. While the slurry has low strength, the weight is light so it doesn't add too much extra stress on the casing or formation. The tail slurry is typically designed at 16ppg as this gives sufficient strength to tack the shoe in place and support to drill through and enter the next hole section.'
The cement job broke down the formation and that was the end of that. But you'd think they would know they were losing fluid by using that new fangled invention called a 'flashlight' and taking a look at the hole at the surface to see if they had fluid all the way to the top. Still more questions. Maybe it was a ty drilling crew. Who knows. I know this, HAD they done that, and saw they were losing fluid you start getting drillpipe in that hole ASAP. But, ends up, they were got the fluid coming BACK at them the other way ....haha...no funny...but..you know. Doesn't sound like they were paying much attention. The bottom line is, the only way you know of what is going on 'down there' is what is going on with your drilling fluid. You want to be able to account for it all. If you're getting it back or losing it, or putting more or less in than you're putting in, something is wrong. ANd if you're getting more BACK, then bad wrong. Blowout. Getting less back, lost circulation.
All moot now. The thing is , the relief well(s) are going to experience the SAME conditions so...we could end up with 2 wells blowing out.
They've got a tiger by the tail down there. Pray for 'em.
Last edited by word; 06-06-2010 at 05:36 AM.
What an excellent and surprisingly enlightening explanation/perspective on the situation.
Word to word, son!
Heard last night that the BP guy told them, when they were getting 'unusual gas pressures' to 'ignore them'.
WTF ?!?!
I'm in New Orleans now. Got here early this AM. We're gonna head south towards Venice later on Wednesday to take a look around and see what we can see.
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