Umm, I frankly (as you all know) knew, until I came here, nearly nothing about wells, period. But, at this point, after DWH sunk, bent the riser, the zone poured forth, all the sand, the, ahem, uncertainties around cementing and the casing, isn’t this about like the final episode of Lost, where they (???) flew the (crashed!!) plane out? Isn’t all this like trying to invoke the gods from some ancient Greek temple or something? Isn’t this whole structure an all but total wreck–and [B][I][U]no one[/U][/I][/B] knows what’s left, and what the capabilities are of what’s left (or can know, because [B][I][U]no one[/U][/I][/B], in the whole wide world, has had ANY experience in anything remotely resembling this situation as it actually, at this point, exists)? Aren’t we beyond the even expertise of all of rlanasa’s PhD’s? Isn’t this like a bunch of people, some mechanics, some engineers, some fans, trying to figure out whether a car will still run 6 minutes into a demolition derby?
[QUOTE=tengineer;38284]I have been asked a question I do not feel qualified to answer as I am only a semi-retired mechanical engineer that occasionally visits oil rigs.
The question is this: Once the relief wells are drilled when will the pressure be relieved to the point where oil stops coming out of the Macondo well?
Will it be instantaneous? I think I know the answers but there are wiser heads with much more experience and expertise than I have that can answer these questions right here on gCaptain.
So, what’s the answer?
Thanks
Tengineer[/QUOTE]
Very generally speaking, once the relief well intercepts the target or blowing well, heavy fluid, usually heavy kill mud at first, is pumped into the target well followed by heavy cement. The target well needs to be penetrated beneath the zone suspected of feeding the blowout. If intercepted above the heavy kill fluid might get blown out as soon as it enters if not pumped in fast enough. As heavy kill fluid fills the target well’s bore from beneath the kick zone upwards it will build height and thus hydrostatic pressure that will eventually exceed the formation or pore pressure from where the oil gas and perhaps formation water is entering the wellbore and eventually kill it ie: Kill mud Hydrostatic pressure > Formation pressure…ie: the inflow of formation fluid is halted by the heavy mud column above it… ie: in text book fashion but we are not sure if the well is blowingout from the casing annuli or the wellbore itself or both…or if sections of the casing has collapsed or if a Hurricane might interrupt operations at a vital stage. It is actually quite a complex and guarded skill carried out by an elite cabal of oilfield specialists. There is no room for bullshit with these guys and they are constantly mindful of what mother nature can throw back at us when we treat her with total disregard. They know their stuff and know what they are up against and the consequences of their actions and always have a plan B and Plan C etc unlike the BS BP con artists who designed this well. Selecting the correct kill pump rate is vital. If kill fluids are pumped too quickly, pressures might cause the well bore to exceed formation pressure and fracture formation exacerbating the bad condition the well is already in. Thanks in part to BP’s cockamamie well planning that called for insufficient cement column height above the last casing/liner shoe with no tie back. Technology used to sniff out metallic casing in the target well is proven and if they miss the first time bear with them, don’t panic …they will eventually hit it on target provided, BP has provided them with meaningful data. Don’t forget this well was side tracked. A relief well does not act as a relief valve. This is a common misconception laymen naturally assume as the name might suggest.
[QUOTE=Alf;38283]I confer… the hardest part will be the kill rate followed by maintaining enough volume (this latter part should be covered with the mud barges etc). One of the crucial parts will be the size of the holes/communication paths they make thru’ the steel 7" casing on the Macondo well.
Barite is an excellent LCM but I’m sure they will be introducing other LCM into their plans. There will be a large amount of co-mixing of mud and oil initially so there is the potential for barite to drop out if the overall flowrate gets low enough. This could cause some problems.
BigMoose earlier mentioned the relief well running parallel to the original well for some distance. This makes logical sense as if they establish a flow path near the bottom of the well, they will then have more options for establishing more holes higher up if the bottom ones plug, give insufficent flow thru’ etc.
Kill mud weights?.. I killed a huge shallow water flow several years ago… it took 3 attempts and about a week to finally stop it. (Our biggest problem was mixing enough 15ppg mud on the rig).
My guess would be they would start with around 14ppg as this is what the relief well will most like have/need at that point in time (the relief wells also need to consider their own individual well control scenarios) then progress to a higher mud weight.
Simple calculations show that the 13ppg sand at 17,821ft will require a minimum of 14.8ppg just to balance the pressure, so with added margins it’s likely to be 15+ppg.
The best LCM is cement… assuming you can get it in the right places in sufficient volumes.[/QUOTE]
I concur some form of LCM will need to be introduced into the well. There will be quite a few other variables they will need to juggle apart from gentle to brute force to heal this well. They might not also need to physically penetrate the well if the know exactly the zone that is feeding it is as they can use fracturing skill to establish communication with this zone and then on up the wellbore.
The record that BP has in safety is not “A Loose Cannon” it is the entire operation. as i said, go compare the safety records. nor is this the result of poor regulation - Oh, poor regulation allowed it to happen, but one would expect a company to function in the best interests of its employees. BP has demonstrated time and again that they operate from a position that says that fines are a part of doing business and cheaper than doing things right. They actively rewarded reduced maintenance costs even when those costs were driven down by managers and others ignoring the needed - necessary repairs. along with that reputation is one of cutting corners - as was done over and over on the DeepWater Horizon.
Regulators are there to keep the company on the straight and narrow and they certainly failed also, but you can’t blame lax regulation for law breaking. CM 1 somewhere has argued that these were willful acts, and there is a history of such willful negligence. There is negligence that happens as someone overlooks something - we can call that an accident, although the negligence remains, but to willfully ignore dangerous situations, that goes beyond negligence. This isn’t a loose cannon, it is a corporate culture that has been totally corrupted from the top on down - go read the responses made to senators and representatives when BP was investigated - these problems aren’t new, there is a pattern. The only way to clean it out is to remove all of top management and the simplest way to do that is break up the company - 10% of that 60,000 may lose jobs, jobs they so richly deserve to lose - the operating assets will remain and while there will be some modification of behavior, it can be done. There is no way that the fellows at the top will change, they’ve lived in a rather sociopathic manner for too long and the fact that they chose to live that way tells the tale. The problem is that there is no way to make the wholesale changes needed at the top. The rot starts in the ecxutive sweet and moves up into the board and down the organizational chart. again, I am not saying anything surprising - go look at BP’s record - its all over the web, Google will be happy to help you find the data. One loose cannon doesn’t create an infraction rate that approaches 100:1 as compared with the rest of the industry - that’s a culture, a culture of saving money by cutting corners that compromised the safety of many many workser, the 11 that died weren’t the first. I know little about casing and the BOP, but I do know human behavior (psychologists do that). This isn’t about accidents, but willful negligence which led to death and the responsible parties are the people who defined this culture. (And please don’t start up on how the guys on the rig should/coulda - resisting your boss when you have a wife and kids at home is a very difficult thing, most people can’t do it.)
[QUOTE=BLISTERS;38289]I concur some form of LCM will need to be introduced into the well. There will be quite a few other variables they will need to juggle apart from gentle to brute force to heal this well. They might not also need to physically penetrate the well if the know exactly the zone that is feeding it is as they can use fracturing skill to establish communication with this zone and then on up the wellbore.[/QUOTE]
Agree… there are lots of unknowns both for the well control experts at the scene, and certainly for us looking in from the outside.
[QUOTE=alcor;38272]Blisters,
You are the perfect example of an ignorant person who knows nothing of when to interpret what the well tells you. I have offered vast amounts of data of when this well should have been closed in. Try 1700 hrs. Look through the posts. You are a fool for commenting without having looked at the charts, a classic example of the sheep. For god’s sake look at the posts.[/QUOTE]
And you Alcor, sound like a spoilt brat with an autocratic upbringing that made no room for alternative views. You always had your way, but not this time. No doubt though you do do have an intellectual understanding of oilfield engineering but your emotional development appears to have been arrested since the age of four. And when you say you are sick of people ignoring the data you have presented here then rest assured you are one hell of a sicko along with the other crazies of you ilk. You need treatment. BP is the sole root cause of this hydrocarbon mayhem of biblical proportions - thanks to the clowns that run this company. You guys will be jailed.
[QUOTE=bigmoose;38280] …The statement by the Admiral of 10 to 12 degree lean, must relate to the lean of the flex joint.
Oh, and as an aside to the “issue” clogging up the forum… Me thinks he is succeeding in diluting the technical content we used to see in this thread. Is this where we want to go?[/QUOTE]
Good observation. Trolls are often paid-shills to misdirect or distract a public blog. So… ignore trolls. Do not feed the trolls!
[QUOTE=Alf;38285]
The debris from jetting and subsequent drilling for the 28 & 22" casing usually leaves behind a big mound of cuttings rather than a crater. On one pic I have seen (some time ago) there appeared to be what I call a “gyration crater” caused by the wobbling of the BOP/WHD combination. Was it there from day 1 or is it more recent… I don’t know.
[/QUOTE]
[QUOTE=BLISTERS;38288]Very generally speaking, once the relief well intercepts the target or blowing well, heavy fluid, usually heavy kill mud at first, is pumped into the target well followed by heavy cement. The target well needs to be penetrated beneath the zone suspected of feeding the blowout. If intercepted above the heavy kill fluid might get blown out as soon as it enters if not pumped in fast enough. As heavy kill fluid fills the target well’s bore from beneath the kick zone upwards it will build height and thus hydrostatic pressure that will eventually exceed the formation or pore pressure from where the oil gas and perhaps formation water is entering the wellbore and eventually kill it ie: Kill mud Hydrostatic pressure > Formation pressure…ie: the inflow of formation fluid is halted by the heavy mud column above it… ie: in text book fashion but we are not sure if the well is blowingout from the casing annuli or the wellbore itself or both…or if sections of the casing has collapsed or if a Hurricane might interrupt operations at a vital stage. It is actually quite a complex and guarded skill carried out by an elite cabal of oilfield specialists. There is no room for bullshit with these guys and they are constantly mindful of what mother nature can throw back at us when we treat her with total disregard. They know their stuff and know what they are up against and the consequences of their actions and always have a plan B and Plan C etc unlike the BS BP con artists who designed this well. Selecting the correct kill pump rate is vital. If kill fluids are pumped too quickly, pressures might cause the well bore to exceed formation pressure and fracture formation exacerbating the bad condition the well is already in. Thanks in part to BP’s cockamamie well planning that called for insufficient cement column height above the last casing/liner shoe with no tie back. Technology used to sniff out metallic casing in the target well is proven and if they miss the first time bear with them, don’t panic …they will eventually hit it on target provided, BP has provided them with meaningful data. Don’t forget this well was side tracked. A relief well does not act as a relief valve. This is a common misconception laymen naturally assume as the name might suggest.[/QUOTE]
Thank you. I have tried to explain to folks that a relief well was just an access to solving the problem, then the real work begins. Your answer was much more precise.
Now, everyone still wants to know how long this process will take?
Your best considered guess would be appreciated.
Tengineer
[QUOTE=dell;38287] Isn’t this whole structure an all but total wreck–and [B][I][U]no one[/U][/I][/B] knows what’s left, and what the capabilities are of what’s left (or can know, because [B][I][U]no one[/U][/I][/B], in the whole wide world, has had ANY experience in anything remotely resembling this situation as it actually, at this point, exists)? …
…Isn’t this like a bunch of people, some mechanics, some engineers, some fans, trying to figure out whether a car will still run 6 minutes into a demolition derby?
Or am I totally, ahem, out to sea?[/QUOTE]
Don’t get those suicide pills out just yet!. The well control experts on the relief wells and assisting bp are experts in their field. They do it for a living, we don’t. They see it every day so to speak, we only see it perhaps a few times in our lifetimes.
You’ve seen them in action before in Kuwait and Irag amongst other places. They have lot’s of expertise and ideas. I would definately want them on my team.
[QUOTE=tengineer;38298]Thank you. I have tried to explain to folks that a relief well was just an access to solving the problem, then the real work begins. Your answer was much more precise.
Now, everyone still wants to know how long this process will take?
Your best considered guess would be appreciated.
Tengineer[/QUOTE]
Even if I were privy to what exactly is going on, on the relief well rigs drilling them now, it is very hard to estimate how long the whole thing will take. If fact it can be quite hard to estimate to estimate how long an exploration well might take to drill to total depth. There might be a layer of very hard rock beneath, there might be a very soft layer prone to fluid losses, we might encounter unexpected high pressures, the drill string could get stuck and they might have to back off and sidetrack past the fish ? Weather is another wild card. Machines break down but there is always back up but so far they are ahead of schedule but once they tag the target well and mill a hole into it, or frac into it, it is a matter of displacing the whole well bottom to top with kill mud ideally speaking that is . But if mud displaced goes up the wellbore and then follows a path into a thief zone already created by high well bore pressures during the blowout , crimping of the riser or top kill job things could get complicated.
[QUOTE=Alf;38299]Don’t get those suicide pills out just yet!. The well control experts on the relief wells and assisting bp are experts in their field. They do it for a living, we don’t. They see it every day so to speak, we only see it perhaps a few times in our lifetimes.
You’ve seen them in action before in Kuwait and Irag amongst other places. They have lot’s of expertise and ideas. I would definately want them on my team.[/QUOTE]
Like you, I have also sealed a few flowing wells before. Even if only water wells, it ain’t easy. Here’s an ineresting tale: I remember working to seal an 80 year old 24" diameter water supply well in fractured limestone that had been blasted with dynamite multiple times and had over 100 yards of material bailed out over decades. It was in the basement of an old skyscraper and we had to remove a couple of hundred feet of pump and 18" drop pipe and line-shaft turbine pump with only chain tongs and block and tackle. The sealing effort had for several days over 30 cement trucks lined up, pouring hundreds of yards of concrete into the well, the casing of which we had perforated with shaped charges. Water pumps throughout the city needed to be shut off during concrete pumping lest they draw concrete into the local reservoir and into their pumping systems. FYI, these are up to 3000 gpm systems right around 100,000 bbl/day equivalent.
Like a few others, I actually am optimistic about the relief wells killing this well. Even if there are loss zones, as long as they can somewhat seal the surface, I’m confident they can kill this well. Of course having a direct connection to upper loss zones (depending on how deep they are) will have an effect, but ultimately the mud (if properly designed) will clog up the permeability of the loss zones and even the reservoir itself and effectively cut off the pressures from the original blown well.
[QUOTE=OldHondoHand;37685]Hey Alf, would you mind clearing up something for me?
I’ve heard that the BOP’s have a fail-safe mode, aka a “Deadman’s Switch,” where if they lose signal from the Rig, they failover to closed. But testimony from the Captain and the OIM was that the explosion must have taken out the controls, thereby preventing them from shutting the BOPs in.
Which is it? True Fail Safe or human intervention required? I know the surface controlled, sub-surface safety valves in a production string require hydraulic pressure to stay open. Lose the source and the valve leaks off and closes. Same concept with BOP, or not?
Perhaps if the BOP stack and logic was re-worked, the fail-over only worked on the test rams? Dunno. Thoughts?[/QUOTE]
Sorry OH, but I missed this earlier.
The Deadman is an automatic system… it requires loss of BOTH hydraulic and electrical signals to the BOP before it will activate.
Correct me if I am wrong… but I believe the testimonies were re the EDS (Emergency Disconnect System) which requires human intervention.
We know the EDS didn’t work (or only partially worked) from the testimonies (and the x-rays they took on the BOP wedgelock).
Why the Deadman didn’t function… I don’t know. I have to speculate that there was still a communcation path… perhaps electrical, after the first explosion.
There is also the big possibility that there is casing in the BOP which prevented any RAM working effectively, which I speculate again could have affected the Deadman system.
[QUOTE=Alf;38302]Sorry OH, but I missed this earlier.
The Deadman is an automatic system… it requires loss of BOTH hydraulic and electrical signals to the BOP before it will activate.
Correct me if I am wrong… but I believe the testimonies were re the EDS (Emergency Disconnect System) which requires human intervention.
We know the EDS didn’t work (or only partially worked) from the testimonies (and the x-rays they took on the BOP wedgelock).
Why the Deadman didn’t function… I don’t know. I have to speculate that there was still a communcation path… perhaps electrical, after the first explosion.
There is also the big possibility that there is casing in the BOP which prevented any RAM working effectively, which I speculate again could have affected the Deadman system.[/QUOTE]
And one appears to be a design problem. The deadman switch activates only when three separate lines that connect the rig to the blowout preventer are all severed: the communication, power, and hydraulic lines. Cameron believes the power and communication lines were severed in the explosion, but it is possible the hydraulic lines remained intact, which would have stopped the deadman switch from activating.
[QUOTE=dell;38264]Umm, before my head explodes, could, like, everyone stop opining, let alone hyperventilating, about applicable (?) federal criminal law? If y’all don’t, I commit that I will retaliate as follows: I will post my opinions on annulars and casing and well design principles and cementing and pressures. I have learned just enough to very dangerous, and I promise, your heads would then all explode TOO.
Federal criminal law is a quite abstruse area, one with which I’m only very slightly familiar. I would expect, when we look back on this tragic, sorry episode a decade from now, most of the people will have gone to jail for rather mundane things like filing false statements with the MMS.[/QUOTE]
Not to mention how incredibly hard it is to prove intent.
[QUOTE=alcor;38209]I worked in the Us for 12 months. Loved it. Love the country, love the low taxes. Hated the food. [B]All the cereal has added sugar[/B].[/QUOTE]
Assuming your knowledge of oilfied is based on deductions like above, I have no reason to believe you know anything.
[QUOTE=Alf;38302]Sorry OH, but I missed this earlier.
The Deadman is an automatic system… it requires loss of BOTH hydraulic and electrical signals to the BOP before it will activate.
Correct me if I am wrong… but I believe the testimonies were re the EDS (Emergency Disconnect System) which requires human intervention.
We know the EDS didn’t work (or only partially worked) from the testimonies (and the x-rays they took on the BOP wedgelock).
Why the Deadman didn’t function… I don’t know. I have to speculate that there was still a communcation path… perhaps electrical, after the first explosion.
There is also the big possibility that there is casing in the BOP which prevented any RAM working effectively, which I speculate again could have affected the Deadman system.
kwCharlie would be a better authority than me.[/QUOTE]
It’s like the Peter Sellers Pink Panther line “that’s not my dog”
That’s not my code, and yes it does bite.
I’m telling you, one of the most important documents to look for is the most recent code from the PLC in the two Pods, down on the stack, and in the PLC in the Sub-Sea house. It’s over 2000 lines of code if I remember right and will be a huge task to see what is suppose to happen when this-or-that is done.
PLC commands are sent down glass fiber to the pod and the PLC at Sub Sea (sending the signals by addressable code) should have had a battery UPS that would have kept it alive with the batteries in the pods keeping that PLC communicating, any failure of communication to the pod is a ‘pull the stack’ problem.
The BOP should have been able to operate if the glass or PLC’s were broken BUT I’m not sure to what degree or what doing it from the Bridge had an effect. That shouldn’t have been the problem, when they pushed the buttons the glass to the pods (down either yellow or blue) and the LED that shines down it to command the stack should have been working, that glass fiber is robust and the PLC had UPS’s.
It was reported to the day TP that the Driller was at the Drill Floor BOP controls BEFORE the fire, the commands should have been sent to at least on pod and the processes initiated and once started they should have completed, I think, all depended on how all those lines of code were written.
With today’s equipment almost EVERYTHING has a SOFTWARE and/or HARDWARE solution or cause. You should have seen the fiasco of HiTec and GE getting Active Heave working on the first ship, the DW Pathfinder, I could have sold tickets, and it took 6 months in the GoM. BUT we took the second ship, the DW Frontier, to New Zealand and drilled in 60 foot contentious swells AFTER we worked out all the hardware (my GE Drives) and software (HiTec’s code) issues.
My feeling is the BOP did work, just couldn’t ‘cut it’
Hope that clears it up, sorry, know it didn’t. It’s a nerd thing that even after 35 years on rigs I still can’t overcome AND I’m talking off my focused expertise, the drives and the code that controls them.
Any floor hands reading along here? If you heard one driller say, “Our well control system can control any kick situation and save your life if we react and implement according to procedure,” and then also heard another driller say, “Our well control system can usually control any kick situation if the engineers and company men and pushers have done their job properly, trust them,” which driller would you want to go out with?
In this highly emotionally charged very verbose discussion here we may have lost sight of what the bottom line is in order to get back to work. Or am I not seeing the forest for the trees?