Gulf of Mexico Oil Rig Explosion

Dreadful sorry for the loss of life. Grateful for those rescued. Sorry we are so dependent upon oil. Grateful for those who provide it.
 
Henning said:
Makes a lot more sense than the rig exploding. What happened was the pressure down hole wasn't what was calculated and the mud wasn't the right weight, same as most every blow out.
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I don't know how accurate the report was but an article from yesterday mentioned they were completing the well. Maybe it was just a temporary completion to test it. Anyway, historically the completion phase is the most dangerous because the well is deliberately unloaded (caused to produce for the non-oilpatch folk). Basically all the equipment to the surface is potentially exposed to well pressure. If all the equipment, both downhole and surface isn't designed, specified,set up, and operated correctly then a bad day is a definite likelyhood.

Although it shouldn't happen, it is concievable that the initial explosion took out all the surface controls for the blow-out prevention (BOP) system. The primary controls are typically in or near the drillers shack which is right on the drill floor. There should be secondary controls which can be remotely operated but the control lines pass under the rig floor to the marine riser which is the conduit to the seafloor. The explosion could have quite easily damaged those lines. The BOP should fail safe but it obviously didn't. I'm sure that folks will be looking at BOP controls among other things as a result of the incident.
 
SCCutler said:
For whatever it's worth, friend of mine who is a safety engineer for a major, tells me that the safety culture is world's away from what it used to be; that they have essentially blank checks to implement best practices for safety.

Also tells me that biggest challenge is breaking the macho-man practices of old-timers. One person at a time.
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In general that's true, but when you're on an intervention to get one of those "Million dollar a minute" wells back up on line, they sing a different song. The reason the management culture and tactics have improved is only because there are some senior company guys sitting in Angola for manslaughter.
 
Henning said:
In general that's true, but when you're on an intervention to get one of those "Million dollar a minute" wells back up on line, they sing a different song. The reason the management culture and tactics have improved is only because there are some senior company guys sitting in Angola for manslaughter.
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While that may be the case the real reason for improved safety procedures and docuementation for ALL industries is $$$. Safety claims cause huge insurance premium increases, lost productivity and higher healthcare costs. It all boils down to MONEY. Corporations are only in existence to make money for you and me, the shareholders. That is why they do everything they do.

Green initiatives = cost savings
Safety programs = cost savings
Diversity = cost savings
 
Anthony said:
While that may be the case the real reason for improved safety procedures and docuementation for ALL industries is $$$. Safety claims cause huge insurance premium increases, lost productivity and higher healthcare costs. It all boils down to MONEY. Corporations are only in existence to make money for you and me, the shareholders. That is why they do everything they do.

Green initiatives = cost savings
Safety programs = cost savings
Diversity = cost savings
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Yep, that's why I said it's generally true until you get on a "million dollar a minute" intervention, then it's "NOW NOW NOW Don't bother rigging that safety....!" Been there too many times.... When the production losses exceed the potential accident losses, safety still goes out the window unless the the Company Man on sight has the balls to stand up to management demands and pressure. The business is still run at the top by the Dick Cheney and GHW Bush types, and if they have to pay out $100MM on a return of $300MM, there is no question of which way they choose. Only the theat of prison changed the MO in that they go to the top person that they can prove in the chain of command issuing the orders. When management uses coercive tactics, ie "You do it or I'll find someone who will!" management assumes the Criminal liability. BTDT when I was relieved for not jacking down a boat in hazardous conditions which contradicted the stability book and company policy and was jacked down by my relief with a total loss of life except one. Email has done more to help this cause than anything because there is a written record of the orders.
 
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Satellite photo 4/25/10

gulf_amo_2010115.jpg


gulf_ali_2010115.jpg


http://earthobservatory.nasa.gov/IOTD/view.php?id=43768&src=eoa-iotd
 
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Let'sgoflying! said:
A blow-out preventer(BOP), a failed safety device.
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???

If the BOP was an option then they would have actuated the blind/shears then released the lower marine riser package and driven or drifted off location after the blow-out. They shouldn't have been in the loop current that far north so they should have been able to get off the stack even with a dead ship.

Obviously that didn't happen. I'm guessing the blow-out destroyed the control lines. Alternatively there are situations where the blind/shears won't work and the annular BOP (with all its weak points) is the only potential barrier left...
 
???
If the BOP was an option then they would have actuated the blind/shears
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All the media places are saying its failure is the 'cause' of the accident. Here is one. (I would not describe it as the 'cause', from what little knowledge I have gleaned about the situation.)
 
Let'sgoflying! said:
All the media places are saying its failure is the 'cause' of the accident. Here is one. (I would not describe it as the 'cause', from what little knowledge I have gleaned about the situation.)
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Well, its failure is the cause of the spill, but the root cause of the accident is the wrong weight mud. If the well is properly balanced the BOP is never engaged, which normally it isn't. It's like any other casualty, there is always a chain of events and multiple individual failures that on their own would not cause a casualty, but when combined cause these events.
 
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Right now there is 2000 psi of seawater pushing down that hole, right Henning? What pressure is that thing producing??
What it might have looked like had it happened on land?
 
Fox News is reporting up to 25,000 bbl per day this morning. This can cause tremendous problems for the Gulf Coast area. Louisiana says they provide 25% of the nation's fish.
Tourism is a major industry. We have a condo reserved in Destin this July. You can bet, folks will cancel reservations faster than one can fold a Japanese fan if oil hits the beaches.
This will also affect future Gulf drilling which the pres recently approved over Gulf Coast state objections. This is why the Gulf coast states didn't want it.

Best,

Dave
 
Let'sgoflying! said:
All the media places are saying its failure is the 'cause' of the accident. Here is one. (I would not describe it as the 'cause', from what little knowledge I have gleaned about the situation.)
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As mentioned the BOP isn't a cause of the blowout. The influx of reservoir fluids (oil & gas) into the wellbore should be prevented by proper mudweight *or* downhole mechanical barriers. If mudweight is insufficient or a mechanical barrier fails then the crew should detect the failure and then the BOP can be used to prevent a disaster caused by the blowout condition.

On a floater (drillship or semi-sub) it is critical to actuate the BOP before reservoir fluids enter the marine riser. If well fluids make it into the riser then there will likely be a bad day. In other words it is likely that the crew detected a problem and actuated the BOP prior to the fire. There should be data onshore that shows what actually happened. We were running real time shore monitoring on the Discoverer 534 back in the early 90s so I'm sure they do much more now.

The BOP has redundant controls and reserve control fluid. A leak in the control fluid piping could cause the BOP to fail but that system typically has some (not a lot) leak isolation capability.

If they had tools in the BOP when they took the "kick" (reservoir fluid flow into the wellbore) then their only option may have been the annular preventer which is much weaker than either pipe rams or blind/shear rams. There may have been too much pressure for the annular or there may have been a leak in the control fluid piping to the annular.

Of course this is all speculation. Someday the realtime data should show us what really happened.
 
Here's a little more info from a Halliburton press release:

"Halliburton had completed the cementing of the final production casing string in accordance with the well design approximately 20 hours prior to the incident. The cement slurry design was consistent with that utilized in other similar applications. In accordance with accepted industry practice approved by our customers, tests demonstrating the integrity of the production casing string were completed."

So they weren't drilling when the blowout occurred. It'd be real interesting to see the well design in order to determine if the "final production casing string" was a long string or a liner. More than one liner hanger has leaked and caused problems when a crew got careless (assumed the liner hanger had a good seal when it actually didn't).
 
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Let'sgoflying! said:
Right now there is 2000 psi of seawater pushing down that hole, right Henning? What pressure is that thing producing??
What it might have looked like had it happened on land?
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Don't know, could be over 10 times that.
 
Henning said:
Don't know, could be over 10 times that.
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Not really. 15,000 ft subsea has a maximum believable pressure of about 17000 psi. The likely pressure is much lower, probably in the range of 7 to 10 thousand psi.

The problem here wasn't overpressure. The likely problem was that a crew either got complacent or that a wellhead casing hanger or liner hanger failed to seat (or latch) properly. It wouldn't be the first time...

Back in 92 I had to push a morning report up the line that included noting that a leaking liner hanger caused a 300 bbl kick and partial evacuation of the rig. Of course the real reason behind the episode was that the crew turned off a pit monitor and allowed the 300 bbl kick but I couldn't report that...
 
Let'sgoflying! said:
What it might have looked like had it happened on land?
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For whatever reason that question made me think of the film "Giant". The only scene I can recall is the one of the well blowing. Of course that's just Hollywood...


Interesting, I don't remember the Connie being in the movie at all.
 
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Clark1961 said:
I've lived that life and find your words rather insulting. When you want to understand the challenges of deepwater drilling, come back and post an honest assessment.
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Looks like the people who were doing the drilling didn't understand it either!
 
Clark1961 said:
Not really. 15,000 ft subsea has a maximum believable pressure of about 17000 psi. The likely pressure is much lower, probably in the range of 7 to 10 thousand psi.
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You'd know it better than I would, I was just the delivery guy. Like I said, I didn't know, I was just going by the pressure ratings I'd see on gear and figuring they'd use around a 1.5 margin, and a lot of the gear I hauled was marked for 30,000psi. The one drilling blow out I was party to was a mud mix problem. Went out and found lots of leaky pipes though....
 
Henning said:
You'd know it better than I would, I was just the delivery guy. Like I said, I didn't know, I was just going by the pressure ratings I'd see on gear and figuring they'd use around a 1.5 margin, and a lot of the gear I hauled was marked for 30,000psi. The one drilling blow out I was party to was a mud mix problem. Went out and found lots of leaky pipes though....
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For maximum possible pressure figure 1 psi per foot of overburden then add the hydrostatic for water depth. The formula works because if the reservoir pressure gradient exceeds 1 psi/foot then generally the reservoir seal is ruptured and starts leaking (this is all deep underground and a natural process).

I've worked a couple projects with reservoir pressure gradient right at the 1 psi/ft figure. Interesting drilling and operation to say the least. Small leaks get your attention really fast.

As a side note: equipment pressure ratings are frequently "working pressure" and they are tested for operation under those conditions. Tests for BOP and valve shells are generally to 1.5 times their working pressure rating. On Shell Oil Company specification equipment we had to do many of the tests with nitrogen rather than water as a working fluid.
 
Tim Cobb said:
Looks like the people who were doing the drilling didn't understand it either!
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I suspect complacency rather than incompetence. The primary well control mechanism (drilling mud) had done its job and cement had been placed to seal the casing to the reservoir.

Some part of the mechanical barrier system failed to do its job. Either the cement wasn't properly placed (or the check in the shoe failed) or a seal on a liner hanger or in the casing hanger failed. Of course monitoring the well for mud flow is the correct back-up procedure to ensure all the mechanical barriers are holding. As I've noted in other posts sometimes folks get lax in monitoring or nobody on the supervisory staff checks on the person doing the monitoring.
 
Everskyward said:
This guy has an incredible story to tell. My question is, is this media sensationalism or do you think there is a lot of truth to it?

http://www.cbsnews.com/stories/2010...90197.shtml?tag=currentVideoInfo;segmentTitle

Video part one

Video part two
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I read the story, sounds right to me. Like I said before, as soon as money starts getting lost and budgets are blown, shortcuts prevail, and BP is kinda infamous for them. I've seen the "chest bumping" in action and have had to settle it before on intervention jobs where the "company man" wanted this and my dive superintendent wanted that. As captain of the boat, luckily I have the ability to put a stop to anything I deem unsafe. IME, the only company I have never seen go "the cheap route" in the safety vs. $$$ decission is Exxon. Why they would bother lightening the mud load before putting the well into production I can't personally fathom. I've never drilled, but I used to run a lift boat with a workover rig that put wells into production, and I don't see how they would have been saving any discernible amount of time and money by doing that. Operating with a known damaged BOP, yeah, that would have been a costly stop and repair, probably cost about $4-5MM, but it should have been done.
 
Here is a tech question from someone who knows zero about oil wells.

If I was concerned about a blowout, I think I would drill a little ie 100', nowhere near the oil or pressure. Then I would pull the tooling out and at this point pour the concrete and put in my valve. (in the media they say they did not pour til after striking the deposit)
Then I would continue drilling (my understanding is that the valve and concrete are not in the way of the drilling tools) to my hearts content, knowing if there is a problem, out comes the tooling and snap shut goes the valve.

Also.....ONE valve? I would want a backup plan as well.
 
Let'sgoflying! said:
Also.....ONE valve? I would want a backup plan as well.
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Not an oil guy either, but my understanding was that 2 control redundant control boxes control the valve. However, 1 was going bad and I can easily imagine the other taking damage when 1 mile of pipe falls.

If this guy is even partially right then this has passed simple fines and enters the realm of criminal negligence.
 
Everskyward said:
This guy has an incredible story to tell. My question is, is this media sensationalism or do you think there is a lot of truth to it?

http://www.cbsnews.com/stories/2010...90197.shtml?tag=currentVideoInfo;segmentTitle

Video part one

Video part two
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Just read the story, didn't watch the vid. Sounds like there's a lot of truth in it considering it's an ET telling the tale.

The damage to the annular preventer is a bit of a stretch. It's not abnormal to move pipe while the annular is closed. Normally the operating pressure on the annular is reduced to the minimum required to maintain a seal before the pipe is moved. The sealing element ("gasket" in the story) is in the "pretty darn tough stuff" category and it will take a lot of pipe moving through it to damage it. Not saying that the element can't be damaged, just sayin' damage is rare.

As for pressure testing against the annular. Yup, that's one of many tests conducted when the stack is tested. The blind rams will also be tested, the pipe rams will be tested, and all the valves will be tested along with the choke and kill lines and the choke manifold.

Still, lots of stuff had to go wrong. The primary cement had to fail. The cement plugs in the casing (if there were any) had to fail. The BOP had to fail. The big red button (emergency shut-down, ESD) had to fail or fail to be pushed. The engine intake shut-offs had to fail or fail to be triggered. It's certainly not the first rig to burn after the ESD was neglected. Of course the rig may have still burned even if the ESD had been tripped.
 
Let'sgoflying! said:
Here is a tech question from someone who knows zero about oil wells.

If I was concerned about a blowout, I think I would drill a little ie 100', nowhere near the oil or pressure. Then I would pull the tooling out and at this point pour the concrete and put in my valve. (in the media they say they did not pour til after striking the deposit)
Then I would continue drilling (my understanding is that the valve and concrete are not in the way of the drilling tools) to my hearts content, knowing if there is a problem, out comes the tooling and snap shut goes the valve.

Also.....ONE valve? I would want a backup plan as well.
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Well, it's complicated. By the time the well gets to 15,000 feet below the mudline there are several strings of casing in the well and the BOP stack is made up of several "valves" which can seal the wellbore in one or more of several different ways.

The annular preventer mentioned in the article can be used to seal the annular space between the wellbore and any pipe or tools in the wellbore. I'fn yer brave and desperate, the annular can even seal the wellbore entirely by itself. Of course, it won't be much good for anything after that until a new element is installed. In actual operation on well control problems the use of annular preventers is generally limited to somewhere between half and three-quarters of it's rated working pressure. Above that pressure the pipe rams must be used. I've been aboard when we had to switch from the annular to the pipe rams on a 5,000 psi rated annular preventer.

Other "valves" in the BOP include pipe rams which are steel and elastomer bits which can form a very high pressure seal in the annular space between the wellbore and a specific pipe diameter. Typically the BOP will have pipe rams sized for the drill pipe and next expected casing outside diameter. Drill pipe and casing can also be moved with the pipe rams actuated but accomodation must be made to pass tool joints or collars. High pressure pipe snubbing units routinely move pipe through pipe rams.

Every subsea BOP includes blind/shear rams. These rams offer a very high pressure seal in an empty wellbore or in some cases can shear pipe and create a seal. The shearing capacity is limited and so it may not be possible to function these rams in all possible circumstances. There is a procedure which must be followed or the shears will likely fail. Trying to operate the shears while a well is blowing-up/burning around you is probably not going to work out real well.
 
Pi1otguy said:
Not an oil guy either, but my understanding was that 2 control redundant control boxes control the valve.
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Yeah, I was thinking two independent valves or other means of emergency shut-off.

If this guy is even partially right then this has passed simple fines and enters the realm of criminal negligence.
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You can sense the pressure to "get it done'.... 00s of thousand$ per hour at stake, no time to lose! This puts all that in a new perspective.

They did not even have a voltage limiter for the platform? (the lightbulbs went too bright and burst, electronics blew when the generators sucked methane), or a governor for the engines?

What happened to risk analysis?
 
Let'sgoflying! said:
They did not even have a voltage limiter for the platform? (the lightbulbs went too bright and burst, electronics blew when the generators sucked methane), or a governor for the engines?
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Seems like the chain was complete and the accident was unavoidable at the point voltage limiters would kick in.

What happened to risk analysis?
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Sadly they probably looked at the $75 million cap on damages combined with the odds of a mishap. Probably annualizes to under a day's profit.
 
Pi1otguy said:
Seems like the chain was complete and the accident was unavoidable at the point voltage limiters would kick in.
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I was just thinking about how the lack of voltage/diesel speed control might be a possible implication of how the general approach to risk assessment was.

Sadly they probably looked at the $75 million cap on damages combined with the odds of a mishap. Probably annualizes to under a day's profit.
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I'd bet, even without new regulation, they will look at that differently now.

All my thoughts are from the armchair assessor, mind you.
 
Where is all the hay going to come from? There is no huge hay surplus in the country, it's what feeds our livestock during the winter. Consider the quantities we're talking about. He just used 1/2lb of hay to pick up a couple of ounces of oil. You'd need to pull all the hay produced in Kansas, Nebraska and Texas in a year to start cleaning this spill up, just covering the edges, as it is, and it's still pumping oil. It might be a solution at the edges that are heading for a beach somewhere, but as for doing a majority clean up, I don't think we have the hay to spare. Have they tried laying Napalm on it yet?
 
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