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    #31
    I can not watch the ROV feeds from home but whenever I can I have them on the screen at work. Once the well is capped I would love someone to put together an ROV movie showing some important/difficult moments and explaining what they are doing.

    Comment


      #32
      Originally posted by Steve.B View Post
      23.40 British Summer time, i am watching the operation to refit the containment cap via Enterprises No2 cam. They have made a few attempts in the last half hour, but each time they have pulled back for various reasons, one try they had a small pipe caught up under the cap, so the ROV moved in to move it aside.

      Is the containment cap being suspended from the surface ship via the connecting pipeline?? If so it must be so hard positioning the cap like they are, inch by inch. Hard to imagine that the cap is on the end of a mile of pipe! But moving it inch by inch they are. If it is suspended from the surface ship, they must have very good compensator's on the lifting gear, the cap is not moving up or down at all, either that or surface conditions are flat calm.

      Fascinating being able to watch all of this live footage from a mile beneath the Gulf.
      As far as I understand they are using an ordinary Marine Riser from the Cap to the Drillship on surface. The riser will have the same ID as the BOP Stack (18 3/4") and with buoyancy elements on part of the joints to take some weight off the LMRP and the support ring and compensators.
      The riser will end with a Slipjoint at surface (above the support ring) to allow for heave and tidal differences.

      One of the problem they have now is that the Discovery Enterprise, being basically a drillship with some processing equipment and storage capacity for well testing, can only handle a limited amount of fluid through the Separator(s) and the flow from the well is way above that.
      The Q-4000 does not have facility to handle and store oil, only to burn off what is coming through the second connection from the BOP Stack.

      So, why not bring in a FPSO with a large processing and storage capacity??
      It is not that simple. There are no FPSOs in the GOM yet and what is available of such vessel doesn't have a DP system to stay on location without a mooring system.

      What baffles me is that they don't try to go in with fishing tools to remove the Drillpipe that is in the hole, now that they have direct riser contact to a Drillship on surface. Once the drillpipe is out of the way it should be possible to go in with a retainer and to spot a pill of very heavy mud just above the leak, even if that require perforating the casing(s) to get to the annulus. Once the well is killed, a cement plug can be set to ensure that it will stay "dead".

      It is not coming up outside ALL casings, which was suggested somewhere. If that happen, the leak at seabed would be around the BOP, not through the BOP. This may occur at an early stage of drilling in relatively soft formations, but not in this case.
      In one shallow gas blow-out I was involved in where that happened, the gas migrated nearly 100 meters away from the well bore. After some time it "bridged over", but came up another place a couple of times, before it eventually found an "escape route" that was "permanent". This was some distance away from the rig, so we could get back onboard, showel dirt for a day or so and finally jack the rig down and get away.

      The gas kept on coming for more than 3 years from that Blow-out, eventually creating a crater more than 1500 ft. wide and 300 ft. deep in the seabed. After abt. 2 years, the 30" Conductor and surface BOP eventually toppled over and disappeared.
      But that was in less than 150 ft. of water and at a drilling depth of less than 2000 ft. Not like here, 5000 ft. of water and a vertical depth of 13,000 ft. or so below the seabed.

      Comment


        #33
        Originally posted by ombugge View Post
        As far as I understand they are using an ordinary Marine Riser from the Cap to the Drillship on surface. The riser will have the same ID as the BOP Stack (18 3/4") and with buoyancy elements on part of the joints to take some weight off the LMRP and the support ring and compensators.
        The riser will end with a Slipjoint at surface (above the support ring) to allow for heave and tidal differences.
        Thanks for the explanation ombugge, the more i learn, the more fascinated i am becoming by this technology.

        Originally posted by ombugge View Post
        What baffles me is that they don't try to go in with fishing tools to remove the Drillpipe that is in the hole, now that they have direct riser contact to a Drillship on surface. Once the drillpipe is out of the way it should be possible to go in with a retainer and to spot a pill of very heavy mud just above the leak, even if that require perforating the casing(s) to get to the annulus. Once the well is killed, a cement plug can be set to ensure that it will stay "dead".
        I guess this would involve reversing the rams that failed to totally severe the riser in the first place? Then in theory they should be able to retrieve the drill pipe (joints) that blocked the rams? I guess that would depend on how much damage the rams did when they attempted to cut through both the riser and the drill, a clean cut through the riser should make it possible, but if the riser is crushed against the drill then maybe the drill will be jammed solid? But if they could remove the obstruction, i guess closing the rams again should then shut off the flow? And if my understanding is correct, no flow would make the mud injection a relatively easy task, compared to trying to pump mud against a constant fast flow of gas and oil.?

        Sounds like a sensible idea, but i am getting the impression they have concerns about losing the wells integrity if they stop the flow. Do they fear the main pipe may have been breached below the seabed somewhere? Not knowing anything about the type of rock they are dealing with down there, and what difference the type of rock would make anyway, i guess it's hard to know what is going through their minds regarding this. All i know is that even if they do manage to make a direct flange connection to the LMRP in a weeks time, they seem certain that they will not use this to shut off the flow, even though in theory this should be possible by fitting a valve in the section they plan to bolt to the LMRP flange - shut the 'top kill' injection valves, shut the new valve, and you have shut off the flow. By not doing this must show that they have serious concerns about the oil and gas simply finding it's own route around the BOP altogether. Then ending up with a situation similar to the shallow gas blow-out you mentioned.

        I am also wondering if it is normal to dig the relief well to such a deep depth - like they seem to be doing in this case? Could they be worried about the integrity of the rock at shallow depths, and they want to get to some good solid rock further down? Makes commonsense if that is what they are doing.
        Your charts, your radar, your eyes and ears - if all 4 agree, you may proceed with caution.

        Comment


          #34
          Originally posted by pilotdane View Post
          I can not watch the ROV feeds from home but whenever I can I have them on the screen at work. Once the well is capped I would love someone to put together an ROV movie showing some important/difficult moments and explaining what they are doing.
          I would also find that interesting to watch, not sure if it's something BP will do though. I was lucky last night to catch the action of the cap going back on, i was about to go to bed, but decided to have a quick look before i turned the pc off. Perfect timing, i could see the cap moving through the water with the whole of the BOP stack looming into view behind it. Bedtime was then canceled!
          At the time i was wishing i had someway to record the footage, but i have no means of recording live streams of video. I even tried to take some 'screen shots', but the captures did not show the video, just a blank media player screen. That was a shame, because the footage of the cap with the whole of the stack coming into view behind it looked rather cool.
          Your charts, your radar, your eyes and ears - if all 4 agree, you may proceed with caution.

          Comment


            #35
            Watching the ROV footage I find it interesting that the oil is not really sticking to anything underwater. The cap, top of BOP, dispersant hose and ROV arms that get into the oil stream all seem clean.

            Comment


              #36
              An interesting links: http://energycommerce.house.gov/docu...esentation.pdf

              This give some answers to how the well was designed and what could be the reason for it going wrong.
              It should also clear up some of Steve's questions in the post above:

              I guess this would involve reversing the rams that failed to totally severe the riser in the first place? Then in theory they should be able to retrieve the drill pipe (joints) that blocked the rams? I guess that would depend on how much damage the rams did when they attempted to cut through both the riser and the drill, a clean cut through the riser should make it possible, but if the riser is crushed against the drill then maybe the drill will be jammed solid? But if they could remove the obstruction, i guess closing the rams again should then shut off the flow? And if my understanding is correct, no flow would make the mud injection a relatively easy task, compared to trying to pump mud against a constant fast flow of gas and oil.?
              Just to clarify; The riser is the bit above the LMRP and Casing is the "fixed" pipes below the Wellhead. The BOP is between the two. Drillpipe moves through the Riser and the Casing and is what gets cut by the Shear Ram. There are also Pipe Rams and Annulus Preventers, which closes around the Drillpipe. Blind Rams can be closed only if the is no pipe in the way, therefore it is necessary to lift the Drillpipe after the Shear Ram has been used to allow the Blind Ram to close off the entire wellbore.

              When the BOP has closed the well, the LMRP can be disconnected from the BOP and the rig can be moved away from the well, without there being any spill. But this is not the same as "killing" the well. That is done by pumping heavy mud down through the "Choke and Kill" lines until hydraulic equilibrium between the formation pressure entering the wellbore and the weight of the mud in the casing above.

              In normal drilling operation, drill mud is pumped down through the Drillpipe to the Drill Bit to cool and lubricate the bit. The mud is returned to surface via the Annulus, which is the "opening" between the Drillpipe and the Casing, lifting the cuttings with it. The mud weight is adjusted to ensure that equilibrium is maintained and the well is not flowing.
              As said in an earlier post, sometimes "under-balanced drilling" is done to increase the penetration rate, which is a controlled operation involving flowing of the well.

              Please bear in mind that in this case they had completed drilling, set a plug to close off the well and reduced the hydraulic pressure in the wellbore by displacing the mud with seawater, in preparation to set a second plug closer to the wellhead. If the bottom plug had been successfully set this would have been a normal and safe operation.

              Another interesting article I found, which illustrate the nationalistic feeling there are in the US, even in the face of such a disastrous situation:
              http://www.nola.com/news/gulf-oil-sp...tml#incart_mce
              They should not refuse any help to clean up the mess, whether inside of outside territorial waters.
              If other nations refuse access to US flagged vessels, there would be all kinds of accusations of protectionism and treat of retaliations.
              Remember when Cuba offered to send their experienced Hurricane Rescue Team to help after hurricane Katrina? They were denied visa.

              Comment


                #37
                Originally posted by ombugge View Post
                Just to clarify; The riser is the bit above the LMRP and Casing is the "fixed" pipes below the Wellhead. The BOP is between the two. Drillpipe moves through the Riser and the Casing and is what gets cut by the Shear Ram. There are also Pipe Rams and Annulus Preventers, which closes around the Drillpipe. Blind Rams can be closed only if the is no pipe in the way, therefore it is necessary to lift the Drillpipe after the Shear Ram has been used to allow the Blind Ram to close off the entire wellbore.
                That gives me a better understanding Ombugge, thank you.

                I did download the investigation document a week or so ago, but i have to be in the right mood in order to fully get my head around all it contains, that needs a lot of concentration and i have been struggling a bit with that lately. But your clear explanation is very much appreciated. It would seem that a few lines of defense have failed within the BOP.
                Your charts, your radar, your eyes and ears - if all 4 agree, you may proceed with caution.

                Comment


                  #38
                  Originally posted by Steve.B View Post
                  It would seem that a few lines of defense have failed within the BOP.
                  It appears that ALL lines of defence has failed in this case.
                  These kind of things are just not going to happen, even in WORST CASE!!!

                  Comment


                    #39
                    One the well is killed will they be able to bring the BOP to the surface for investigation?

                    If I read Ombugge's .pdf Energy Commerce link correctly on page 16 does that mean they tested the BOP and at least that part functioned properly?
                    Last edited by pilotdane; June 30th, 2010, 18:32.

                    Comment


                      #40
                      Originally posted by pilotdane View Post
                      One the well is killed will they be able to bring the BOP to the surface for investigation?
                      I believe that is correct. I also think that there are going to be one hell of a lot of people very interested in finding out exactly what went wrong with it.

                      Can you imagine the attention that bit of kit is going to get once it breaks surface? Not only will there be an army of engineers waiting for it, but you just know that the government will also have their own people waiting for it, lot's of agents will be there to insure that any defects found are not covered up in anyway. I have a feeling that once on the surface, that BOP is going to point a big finger of guilt in someones direction, and boy, i am glad it's nothing to do with me!
                      Your charts, your radar, your eyes and ears - if all 4 agree, you may proceed with caution.

                      Comment


                        #41
                        Originally posted by Steve.B View Post
                        I believe that is correct. I also think that there are going to be one hell of a lot of people very interested in finding out exactly what went wrong with it.

                        Can you imagine the attention that bit of kit is going to get once it breaks surface? Not only will there be an army of engineers waiting for it, but you just know that the government will also have their own people waiting for it, lot's of agents will be there to insure that any defects found are not covered up in anyway. I have a feeling that once on the surface, that BOP is going to point a big finger of guilt in someones direction, and boy, i am glad it's nothing to do with me!
                        Yes, there will be a lot of attention around the BOP, once it is recovered. First of all, why didn't the Fail-safe function? But just as important is why they were not able to manipulate it, once the ROVs were in place?
                        Or when they managed to connect to at least one of the pods?
                        This is a "standard" BOP Stack of a tried and tested design, but are there any flaws in the design, or in the standards that applies?
                        Why aren't there simple mechanical means of closing the rams, using an ROV?
                        (Look at an earlier post of mine which show a large "Surface BOP Stack" with large "Wheels" to close the rams manually)
                        Why isn't there direct connection on each ram to allow by-pass of all faulty functions in the control system?
                        I have already mentioned several times the lack of Acoustic Remote Emergency Operation System for BOPs used in the Gulf of Mexico.

                        The list of questions are endless!!!

                        Comment


                          #42
                          , is unsustainable
                          A U.S. Senate committee voted on Wednesday to eliminate
                          limits on liability that oil companies would face for oil spill damages. Companies currently enjoy a $75 million cap for compensating local communities for economic losses and cleaning up environmental damage.
                          The change, if approved and enacted into law, would apply retroactively to BP. Democrats in both the Senate and House of Representatives have made the legislation a top priority.
                          What is this???
                          Is it legal to change the law after the event, and then make it retroactive for an event that has already happened?

                          BP has not tried to limit their liability to USD 75 mill., while the other partners in the concession, Transocean, Halliburton and Schlumberger are trying to get out of any responsibility what so ever by claiming that BP was not just negligent, but reckless.

                          If a host nation can change the rules at any time, at their own accord and without regards to internationally accepted rules and regulations, then where is open and transparent legal system?

                          Nobody can predict where and who will suffer the next oil spill, be it from a blow-out, or from a tanker collision, grounding or fire.
                          Underwriter would have to increase the premiums for P&I coverage drastically to cover the risk of astronomical claims from any state that is hit by such an event. USA will have lost their moral standing to protest, if the "sinner" should be an American company.

                          This open for a "free-for-all" for anybody with a claim, legitimate or otherwise, to try to extract compensation of any size for real or imaginary damages to the environment.

                          I will repeat what I have said before; the biggest man-made oil spill was in the Persian Gulf during the Iran/Iraq war and the first Gulf War. Millions of barrels (est. >5 MMbbls.) were spilled from sunken VLCCs, damaged production platforms and, finally, from opening up and flowing hundreds of well in Kuwait.

                          What was the environmental damage? Very limited. In fact the next year the prawn fisheries off Kuwait was the best it had been in years, mainly because there had been a year of no catching, allowing the prawns to recover and feed on the abundance of small organisms feeding on the oil. Tarballs that was present in the nets had shellfish growing on them.
                          Nature is resilient and will recover from this spill, as it has from many others.

                          What about drilling in deep water anywhere? Or to drill for Offshore oil at all? Will the risk of being hit by an unlimited claim in case of an accident make the Oil Companies, especially the small independent Operators, just simply too afraid to try anything new?

                          How will the US cope with less and less domestic oil to feed their insatiable thirst for oil? Could something good come off this, making the Americans realize that their way of using the world's resources without consideration for others, the future, or the environment, is unsustainable?

                          Especially the last is probably a bigger environmental catastrophe than any amount of oil spilled into the Gulf of Mexico.
                          Last edited by ombugge; July 4th, 2010, 04:23. Reason: Added text for clarity

                          Comment


                            #43
                            None of this surprises me anymore. With the American government in their current state of mind with regards to deep sea oil drilling, i guess anything could happen. Bringing in a new law and then back dating it a couple of months seems more than likely. Would that be against the law?, depends on who's making the laws i guess. At the end of the day it all comes down to politicians simply wanting to score votes with the public. I for one simply detest it when such parties try to gain votes out of various situations, they are simply more concerned about saving their own image rather than dealing with the matter in hand in a sensible way.

                            At the end of the day people need to remember a simple fact This was an accident - not a deliberate act. So many people are acting as if this disaster was guaranteed to happen with the way that well was drilled. I personally believe that neither BP or TransOcean would ever conduct an operation if they felt there was a chance of this happening. It was an accident, and like all accidents, the trick is to learn from it, so just let the company get on with it without smacking them over the back with a baseball bat whilst they are trying to do it. All the screaming and shouting in the world is not going to get that well under control any quicker. The people that live around the GOM and other affected areas must want this leak stopped as soon as possible, but i can guarantee that nobody wants this leak stopped more than BP does. With this compensation free for all, it would seem that the only people that are going to lose out of this are BP and the millions of people worldwide that have money invested with them - be that directly or through investment companies and pensions etc.

                            Anyway, back to the task in hand. Listening to the latest tech reports (dated 28th June),it is good to hear that the first relief well is progressing ahead of schedule, they are now running parallel to the Macondo well at a distance of twenty feet. They were at a measured depth of 16,770 feet on the 28th June. Interesting to note that when they started to drill they were 2,800 feet from the original well in the horizontal plane, now down to 20 feet.

                            They reckon they will be drilling for another 900 feet, for the first 700 foot they will gradually bring the range down to 5 feet, and then the final 200 feet will bring them to the final intersect point.

                            In one of my earlier posts i asked why the relief well had to be so deep, from the latest tech briefing i think i am beginning to understand why. I can see two obvious reasons. First would be the shear weight of the mud in the relief well, that alone may well instantly equal the pressure from the original well, but if for some reason it does not, maybe higher than expected pressures, then mud will then start to travel up the original well, the more mud that travels up, the greater the pressure pushing down. By intersecting the original well so near to the oil reservoir, they have effectively doubled the amount of mud they can have pushing down. In fact they would more than doubled the amount because you have to take into consideration that the relief well is a greater length than the original well - the original well was vertical, the relief well at an angle, like i mentioned above, they started to drill the relief well 2,800 feet from the macondo well.

                            With regards to the oil itself, lets not forget that it is a natural product, i doubt you could get anything much more organic than oil itself. We think that this leak is bad, but what would happen if one day a large underwater earthquake managed to unleash a complete oil reservoir in one foul swoop? I know the chances of it happening must be very small, lets face it, oil is formed over millions of years, so i guess it only gets that chance inside rock that is stable, and not prone to seismic activity. But it could happen. Then there would be one hell of a mess. And no doubt somebody would find a way of blaming the oil industry!
                            Your charts, your radar, your eyes and ears - if all 4 agree, you may proceed with caution.

                            Comment


                              #44
                              Originally posted by Steve.B View Post
                              ...This was an accident - not a deliberate act. ..
                              Ah, but this is the United States where accidents do not exist. Yes, accidents do happen but someone is always at fault and someone always gets sued.

                              I don't know if it made the world news but in the USA a child was killed when hit on the head with a baseball hit by an aluminum bat. The manufacturer of the bat, Louisville Slugger, was liable for the child's injury because they did not properly warn about the dangers of the bat. I am quite surprised that the manufacturer of the ball did not also get sued.

                              http://www.usatoday.com/sports/baseb...-lawsuit_N.htm

                              Comment


                                #45
                                Dane, I thought I was an old cynic and a realist, but you beat me to the post.!!!!

                                I'm NOT anti-American, but your legal system is why I would NEVER want to live there.

                                Democracy is NOT synonym with stupidity, but what goes for a legal system in the USA is!!!

                                How much does it cost the society, the "small people" especially, is unfathomable. Oooobs, did I make a PR mistake here?????

                                I'm NOT anti-American, only anti-hypocrisy!!!

                                Comment

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