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Transocean Deepwater Horizon-What Happened?
About The Rig

Deepwater Horizon was a semi-submersible drilling rig  built in 2001 to withstand the worst of natures elements. The DEEPWATER HORIZON was a Reading & Bates Falcon RBS8D design semi-submersible drilling unit capable of operating in harsh environments and water depths up to 8,000 ft.

The platform was owned by Transocean and leased to BP through September 2013. In September 2009, she drilled the deepest oil well in history. Deepwater Horizon sank on April 22, 2010, as the result of an explosion two days earlier that took the lives of 11 of her crew.




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What Actually Happened?

On Friday, April 30th 2010, an anonymous caller contacted the Mark Levin Show to clarify the events that preceded the Deepwater Horizon tragedy. Below are his account of those events.




Find more videos like this on Drilling Ahead ________________________________________________________________

What Was The Cause?

No official cause of the explosion has been released and likely won't be for sometime to come. All we know now is that Deepwater Horizon had just completed drilling and had cemented casing in place. Cement plugs were set and work began on riggging down 5000' of riser from the sea floor. Heavier mud in the riser was displaced with sea water reducing the hydrostatic pressure below.

What follows is speculation.
  • Some say the well kicked because of a bad cement job.
  • Others theorize that "gas cut mud" caused the kick.
  • It's also being reported that the Blowout Preventers failed.
  • Internet reports circulate that a light weight  type nitrogen/cement was used because of problems with Loss Circulation. Some say this was a difficult  type of cement job to accomplish.

Whatever the reason for the kick, we know this to be true. Gas entered the wellbore and escaped past the cement plug then migrated to the surface increasing in pressure as it rose.

Apparently the Blowout Preventers were opened or breached, allowing the gas to quickly displaced 5000' of seawater in the riser shooting it 200' to the crown of the drilling rig. This rapid reduction of hydrostatic pressure on the wellbore allowed even more gas to enter the well until it finally emptied the hole of fluid. With nothing to stand in its path, the gas engulfed the Deepwater Horizon until it found a source of ignition.

Usually signs of a kick can be seen monitoring a well. Why those signs were not present or monitored during this tragedy is the question that we all are asking.

 
We have the systems & equipment in place to drill safely at these depths, that has been proven. What happened in this particular event we may never know.

 Speculation continues, even here.
________________________________________________________________

Our Brothers Lost

What is real, factual and undisputed is 11 fine hard working men, husbands, sons & fathers, won't be returning home to their families. Those who survive them are broken, their lives shattered as they mourn the loss of those that they  loved and lost to the Deepwater Horizon.

We honor these men here

  • Toolpusher- Jayson Anderson
  • Driller- Dewey Revette
  • Asst. Driller- Donald Clark
  • Asst. Driller- Stephen Curtis
  • Crane Operator-Dale Burkeen
  • Derrickhand- Roy Kemp
  • Floorhand- Karl Kleppinger
  • Floorhand - Shane Roshto
  • Floorhand- Adam Weise
  • MI Swaco-Gordon Jones
  • MI Swaco-Blair Manuel

Below is a tribute to the lives of these men of the Deepwater Horizon and the families they leave behind


Find more videos like this on Drilling Ahead


New Update May 6th 2010 Transocean Deepwater Horizon


This Just In...
Guys, I received this in email earlier. It appears to be legit and is an account of operations on Deepwater Horizon at the time of explosion by an individual who was there. I am going to post the text of the email here 'as is" for you to toss around and give your thoughts on. Please do not ask me for information other than what is posted below. I cannot and will not reveal anymore information about the source.


...They had set A 9-5/8 Tapered Production Liner, did their cement job, had positive tested, and also negative tested, they were going to set a balanced plug around 3000' below the well head which would be at about 8000', the senior company man wanted to set the balanced plug in mud, but the engineers wanted to displace with water prior to setting balanced plug, so they displaced from 3000' below mud line, and were getting ready to set plug. The derrickman called the driller and said he needed help, he had mud going everywhere, and about this time the drill floor disapeared, then there was an explosion, then a second explosion.

The flames are now going straight up allowing evacuation of men, then you know the rest.

The hands that are missing are the ones that were on the drill floor and pump room. You know the results of that. This all took place in less than a minute.

Rig was evacuated in about 25 minutes.

It is believed that the seal assembly at the well head gave up. If that is the case and they would have set the balanced plug in mud then displaced the riser, it would only have delayed what happened by a couple of hours.

Gas must have channeled through the cement job and up the back side of the 9-5/8 production casing.

This is all I know at present."

 

What follows below was also attached to the email and is a 3rd party account/opinion in his own words


"I continue getting calls asking what happened on this problem so here’s a response from a friend in the oil business with possible inside info on the blowout. Please keep in mind this is an “UNOFFICIAL” report so this may or may not be factual. However, the scenario as written makes reasonable sense as far as I am concerned. The focus needs to be on well control now and not speculation as to what may or may not have happened. BP, the MMS and most likely a third party will certainly provide a very in-depth investigation which will be the official report. Having said that I would certainly not look forward to a copy of that report as it will be furnished only to those in need due to the possible liabilities of the findings."

 

 Details as conveyed to me:                

This well had been giving some problems all the way down and was a big discovery.  Big pressure, 16ppg+ mud weight.   They ran a long string of 7" production casing - not a liner, the confusion arising from the fact that all casing strings on a floating rig are run on drill pipe and hung off on the wellhead on the sea floor, like a "liner".  They cemented this casing with lightweight cement containing nitrogen because they were having lost circulation in between the well kicking all the way down. 

 

The calculations and the execution of this kind of a cement job are complex, in order that you neither let the well flow from too little hydrostatic pressure nor break it down and lose the fluid and cement from too much hydrostatic.  But you gotta believe BP had 8 or 10 of their best double and triple checking everything. 

 

On the outside of the top joint of casing is a seal assembly - "packoff" - that sets inside the subsea wellhead and seals.  This was set and tested to 10,000 psi, OK.   Remember they are doing all this from the surface 5,000 feet away.  The technology is fascinating, like going to the moon or fishing out the Russian sub, or killing all the fires in Kuwait in 14 months instead of 5 years.  We never have had an accident like this before so hubris, the folie d'grandeur, sort of takes over.  BP were the leaders in all this stretching the envelope all over the world in deep water. 

 

This was the end of the well until testing was to begin at a later time, so a temporary "bridge plug" was run in on drill pipe to set somewhere near the top of the well below 5,000 ft.  This is the second barrier, you always have to have 2, and the casing was the first one.  It is not know if this was actually set or not.   At the same time they took the 16+ ppg mud out of the riser and replaced it with sea water so that they could pull the riser, lay it down, and move off. 

 

When they did this, they of course took away all the hydrostatic on the well.  But this was OK, normal, since the well was plugged both on the inside with the casing and on the outside with the tested packoff.  But something turned loose all of a sudden, and the conventional wisdom would be the packoff on the outside of the casing.

 

Gas and oil rushed up the riser; there was little wind, and a gas cloud got all over the rig.  When the main inductions of the engines got a whiff, they ran away and exploded.  Blew them right off the rig.  This set everything on fire.  A similar explosion in the mud pit / mud pump room blew the mud pumps overboard.  Another in the mud sack storage room, sited most unfortunately right next to the living quarters, took out all the interior walls where everyone was hanging out having - I am not making this up - a party to celebrate 7 years of accident free work on this rig.   7 BP bigwigs were there visiting from town.

 

In this sense they were lucky that the only ones lost were the 9 rig crew on the rig floor and 2 mud engineers down on the pits.  The furniture and walls trapped some and broke some bones but they all managed to get in the lifeboats with assistance from the others.

 

The safety shut ins on the BOP were tripped but it is not clear why they did not work.  This system has 4 way redundancy; 2 separate hydraulic systems and 2 separate electric systems should be able to operate any of the functions on the stack.  They are tested every 14 days, all of them.  (there is also a stab on the stack so that an ROV can plug in and operate it, but now it is too late because things are damaged).

 

The well is flowing through the BOP stack, probably around the outside of the 7" casing.  As reported elsewhere, none of the "rams", those being the valves that are suppose to close around the drill pipe and / or shear it right in two and seal on the open hole, are sealing.  Up the riser and out some holes in it where it is kinked.  A little is coming out of the drill pipe too which is sticking out of the top of the riser and laid out on the ocean floor.   The volumes as reported by the media are not correct but who knows exactly how much is coming?

 

2 relief wells will be drilled but it will take at least 60 days to kill it that way.  There is a "deep sea intervention vessel" on the way, I don't know if that means a submarine or not, one would think this is too deep for subs, and it will have special cutting tools to try to cut off the very bottom of the riser on top of the BOP.  The area is remarkably free from debris.  The rig "Enterprise" is standing by with another BOP stack and a special connector to set down on top of the original one and then close.  You saw this sort of thing in Red Adair movies and in Kuwait, a new stack dangling from a crane is just dropped down on the well after all the junk is removed.  But that is not 5,000 ft underwater.

 

One unknown is if they get a new stack on it and close it, will the bitch broach around the outside of all the casing?? 

 

In order for a disaster of this magnitude to happen, more than one thing has to go wrong, or fail.  First, a shitty cement job.  The wellhead packoff / seal assembly, while designed to hold the pressure, is just a backup.  And finally, the ability to close the well in with the BOP somehow went away. 

 

A bad deal for the industry, for sure.  Forget about California and Florida.  Normal operations in the Gulf will be overregulated like the N. Sea.  And so on.

 

For everyone interested you can follow this discussion and post your comments in our discussion "Transocean Deepwater Horizon-What Really Happened?" on our Drilling Ahead site.

_ ______________________________________________

Update May 10th 2010
BP Technical Briefing

BP Technical Briefing Image

Today BP held a technical update with the press. Here is what I took away after watching the meeting.

A smaller containment dome referred to as a "Top Hat" could be deployed in 72 hours.This vastly smaller containment dome would limit the amount of seawater that was inside the dome. The logic is "less seawater/less frozen hydrates" to  plug the outlet in the dome. BP has received EPA approval to inject methanol into this dome as a deicer to help stop the formation of this frozen slush. Because of its smaller size the "Top Hat" will not be as effective in capturing the escaping oil.
 
Another option on the board is the "Hot Tap" which would tap directly into the riser and bring the oil to the surface.

Attempts continue to  stem the flow of oil from the Blowout Preventers
Subsea Blowout Preventer Diagram Photograph
  A "Top Kill or Junk Shot" involves attaching mud lines from the surface into the choke and kill lines of the Blowout Preventer then pumping fluids with pieces of rubber and other debris into the well through the kill line and choke line in hopes that the "junk" will plug the leaks in the Blowout Preventers.

 The "Control Pod" of the BOP's have been removed using submersibles and returned to the surface where the malfunctioning electronics are being refurbished.

 This control pod will be returned and attached to the BOPs using the submersible. The control pod allows the operation of controls & valves  on the "kill and choke lines" Repair & re-installation is an important step in proceeding with the Top Kill.

The Junk Shot material (Rubber,Golf Balls Rope,etc.) will be used to plug oil & gas leaks within the Blowout Preventer. Several attempts and "recipes" of varying junk material can be pumped into the Blowout Preventer if necessary.

 If successful, and the Blowout Preventer leaks are stopped then a surface ship can connect to the Blowout Preventer Kill & Choke lines to stop the flow of oil/gas from the well using weighted mud. Weighted mud would increase the hyrdostatic pressure in the well and act as a temporary plug until the well can be permanently cemented and abandoned A second relief well will be "Spudded" or started in the next 7 days.

Do you have a suggestion or comment for British Petroleum on how to contain this well? BP has provided a special email form to hear your suggestions.

 You can reach that form here
___________________________________________

Update May 11th 2010
Halliburton Testimony and Well Schematic released Today
Tim Probert testified today before the Committee on Energy and Natural Resources in the U.S. Senate.
Below is an excerpt of that testimony.

"Operations preceeding the Catastrophic Loss of Well Control on Mississippi Canyon 252 Well.

I need to start this section with an important statement of disclosure. Halliburton, as a service provider to the well owner,is contractually bound to comply with the well owner's instructions on all matters relating to the performance of all work-related activities. It is also important to understand the roles and responsibilities of the various parties involved in the construction of a well. The construction of a deep water well is a complex operation involving the performance of numerous tasks by multiple parties led by the well owners representative, who has the ultimate authority for decisions on how and when various activities are conducted.

Attached to this testimony is an illustration showing the approximate depths and positions of the casing and liner strings set in the well. In addition, the approximate position of the various cement placements is illustrated, which is consistent with the well design. It should be noted that cement is used at specific designated spots and is not designed to be a complete barrier through the entire wellbore.

Cement can be used to isolate formation fluids, to prevent movement of these fluids between formations and to bond and support the casing. A mixture of cement, water and chemicals is combined in a slurry that can be pumped into position around the outside of steel liners and casing. there are many external factors that impact the design and execution of a cement job. These include the variability in hole geometry, relative location of hydrocarbon zones, hydrocarbon content and the prior condition of the wellbore and associated fluids as determined by the drilling fluid provider. Casing strings are typically run with devices to centralize the casing concentrically in the wellbore and prevent incomplete displacement of drilling fluid, or "channeling".

While every effort is made to complete a cement job with the highest levels of mechanical and hydraulic integrity, the above mentioned well conditions may prevent this. Confirming cement integrity after placement would require the well owner to direct the wireline provider to obtain cement evaluation logs. Based on the findings of these logs, the well owner can elect to perform remedial action by perforating the casing and "squeezing" cement into remaining voids to improve the integrity of the original cement.

The centralizer placement on the production casing, the drilling fluid conditioning program prior to cementing and cement slurry and placement design used for this well were implemented as directed by the well owner. However, as shown in the attached diagram, by design there is no continuous cement column throughout the entire wellbore.

Approximately 20 hours prior to the catastrophic loss of well control, Halliburton had completed the cementing of the ninth and final production casing string in accordance with the well program.
Following placement of 51 barrels of cement slurry, the casing seal assembly was set in the casing hanger. In accordance with the accepted industry practice,
 as required by the MMS and as directed by the well owner, a positive yest was then conducted to demonstrate the integrity of the production casing string. The results of the poitive test were reviewed by the well owner and the decision was made to proceed with the well program.

The next step included the performance of a "negative" test, which tests the integrity of the casing seal assembly and is conducted by the drilling contractor at the direction of the well owner and in accordance with MMS requirements. We understand that Halliburton was instructed to record drill pipe pressure during this test until Halliburton's cementing personnel were advised by the drilling contractor that the negative pressure test had been completed, and were placed on standby.

We understand that the drilling contractor then proceeded to displace the riser with seawater prior to the planned placement of the final cement plug, which would have been installed inside the production string and enabled the planned temporary abandonment of the well. Prior to the point in the well construction incident plan that Halliburton personnel would have set the final plug, the catastrophic incident occured. As a result, the final cement plug was never set.

Halliburton is confident that the cementing work on Mississippi Canyon 252 well was completed in accordance with the requirements of the well owner's construction plan.

Thank you for the opportunity to share our views."

Well Schematic
Mississippi Canyon 252-#1-01
Casing Size and Depth

Rig Floor to Sea-75'
Water Depth-5,067'
36"-5,321'
28"-6,217'
22"-7,937'
18"
-8,969'
16"-11,585'
13 5/8"-13,145'
11 7/8"-15,103'
9 7/8"-17,168'
7"X 9 7/8"-18360'
Well Schematic Mississippi Canyon 252-

Read the Entire Halliburton Testimony Here


 __________________________________________

Update May 13th 2010


A great deal of new information just became available
 Please check this link


Hearing on "Inquiry into the Deepwater Horizon Gulf Coast Oil Spill"


Notes from Halliburton Last 2 Hour chart

(What is listed below I believe are indications of the Kick)
Please click to view the Halliburton chart

  • From 20:10-20:34 Hrs.-  gained 290 bbls in the pits while pumping (21:10-21:24 Units of Gas Increasing)

  • From 21:10-21:18 Hrs.-  transfered around 160 bbls out of the system.

  • From 20:18 Hrs.-  steady gain of mud  (22 bbl) until the rig exploded at 21:48

  • @21:30 Hrs (18 minutes before the explosion) flow into the well stopped but standpipe pressure remained at 1200 psi then rose to 1700 psi, fluxuated some and then climbed to 5800 psi with no pumps running.This would indicate most likely they had shut the well in until it exploded at 21:48 Hrs.( This would be close to the max psi rating of the annular)
 Cut away of the final moments recorded on  the Halliburton rig monitor
Halliburton Rig Monitor at time of explosion

Possible explanation could be that the annular was closed as a first defense and failed when it reached its max psi rating  (pipe rams for some reason did not hold) I will be updating this more here


Things we now know from the IADC daily drilling report.

  • The mud weight in the hole was 14.0ppg
  • The casing was cemented and WOC time was 16.5 hours before pressure testing (This could be the kicker if the cement was not fully set, the added pressure in the casing would have expanded it, and created a micro-annulus in the cement or fracturing it allowing gas and oil to migrate up into the annulus).
  • They were working with a 3-1/2" tubing stinger, 817.70ft + 2 crossovers to get it to 6-5/8 DP.
  • The balance of the string was 6-5/8" 32# DP to the rig floor
  • They did run in and displace the hole and riser to seawater at 8,067ft (3,000ft below seabed)
  • They did run and pressure test the casing hanger seal both positive test to 10,000psi and a negative test to 1,400psi. Both were good.
  • We now have a stack layout drawing, showing ram arrangements.
  • The casing was 9-7/8" 62.8# which is 5/8" wall and 8-5/8" ID
  • The 7" properties are still unknown.
Also See

 Transocean Deepwater Horizon BOP Test Results
*Note in this .pdf that the Casing Shear Rams 'Do not function as per exemption"

BP - What Could Have Happened?

BP - What We Know

Halliburton - Last 2 hours before end of transmission

Transocean - Daily Drilling Report, April 20, 2010

BP - Blowout Preventer Testing Memo

Transocean - Deepwater Horizon BOP Assurance Analysis, March 2001

Transocean - Surface BOP Operations from Floating Vessels

BP - Regional Oil Spill Response Plan

Transocean - Deepwater Horizon BOP Test, Feb. 12, 2010

Internal BP Email Regarding Negative Test Results

Follow this discussion on Drilling Ahead Below

Transocean Deepwater Horizon Explosion
A Discussion of What Actually Happened?
 ______________________________________________________________

Update May 15th 2010

BP Releases Cutaway View Of Relief Well Progress

Click On Image For Large View



BP Releases Riser Insertion Tube Drawing
Click On Image For Large View

How it works

  • The insertion tube is a five foot long steel pipe about four inches in diameter with specially designed rubber baffles. The tube will be inserted into the Horizon’s riser to provide a direct connection.
  • The direct connection, combined with the injection of methanol, will minimize the formation of hydrates that could block the flow of hydrocarbons.
  • The riser insertion tube will be installed about 600 feet from the wellhead.
  • The insertion tube will be connected to a 5,000 foot riser that will convey the hydrocarbons to the Transocean Discoverer Enterprise drillship on the surface.
  • Once in place, oil will flow up into the Enterprise’s riser to the surface.
  • Once at the surface, the hydrocarbons will be processed and oil will be separated from water and gas. The oil will then be temporarily stored before being offloaded and shipped to a designated oil terminal onshore.
  • The Enterprise is capable of processing 15,000 barrels of oil per day and storing 139,000 barrels.
  • A support barge will also be deployed with a capacity to store 137,000 barrels of oil.

What's next

  • This riser insertion tube is on site and is being prepared for installation in the next few days.
  • ROVs will assist in the installation and connections to the riser (tubing) back to the surface.

_____________________________________________________________
 

Update May 19th 2010

BP Releases New Drawings of Progress

The 2 images below were released by BP today and detail progress on relief wells and and update on the riser insertion tool. Please click on the images to enlarge them in a new browser window.

Relief Well Progress Diagram


                       (Click On Image To Enlarge)



Riser Insertion Tool Diagram



                          (Click On Image To Enlarge)


Riser Insertion Tool Video
This is the May 17th video of the tool being inserted in the riser

Find more videos like this on Drilling Ahead


Also Today...
This came in my email today from a Drilling Engineer unrelated to BP. I will post it here for you to digest.


Curtis,

The foam ball is used to wipe the drill pipe after every cement job, it's just cheap insurance. if they used foam cement it would have been wiped from the DP by the top plug launching dart during the cement job displacement.

But you are right on the putting pressure in the casing, It's a super bad idea except when landing the top plug, immediately after cement placement. And I agree with the idiotic reasoning that is behind not doing a CB: on a production string, in 25years offshore I have Never & I mean Never heard of one not being done, if for no other reason than finding the top of cement in the annulus.
I have my grave doubts as to the cement integrity anyway, that is an awfully long ways to pump 5obbls of cement and it not get contaminated in 12,000ft of 9-7/8" casing, even using the best cementing plugs, and the plugs for a tapered string are not very good at wiping the casing, the wings are too floppy to be effective at wiping the casing in front of the cement in the larger size casing. The only one I have ever done, we set a drillable bridge plug in the small casing and stabbed in with 4-1/2 drill pipe to do the cement job, And we definitely did a caliper log before hand to make sure we pumped enough cement to cover the production zone fully and cover 200ft of the last casing shoe. And definitely drilled out the plug and did a CBL afterwords. Leaving an area of unsealed open hole that would be exposed to the surface via the annulus is just plain idiocy. 
_______________________________________________________

 Update May 20th

BP says more oil than estimated is gushing into Gulf

BP has said more oil than the 5,000 barrels a day it initially estimated is flowing from a burst oil well into the Gulf of Mexico.

The energy giant said a long tube it inserted into the gusher at the weekend was now siphoning 5,000 barrels a day, but that more was escaping.

'A little more'
 
BP had stuck by its first estimate that some 5,000 barrels, or 210,000 gallons, a day of crude was leaking from the well - despite claims from several experts that the figure was at least 10 times higher.

But BP spokesman Mark Proegler told news agency AFP on Thursday: "Now that we are collecting 5,000 barrels a day, it might be a little more than that."

He would not estimate how much more.

  "We said from the beginning, our experts have been saying there really is no reliable way to estimate the flow from the riser."
______________________________________________________________
                                      
Transocean Says Cement Blew Out Of Well

New details about a deadly oil-rig explosion in the Gulf of Mexico emerged on Wednesday as the owner of the rig suggested that cement blew up through the well and said that federal regulators didn't oversee tests of a critical safety device.

Transocean  Chief Executive Steve Newman, whose company owns and operated the rig leased by BP  told lawmakers that he was aware of reports that a vessel alongside the rig reported receiving cement-like debris on its decks after the explosion.

"For the well, the cement that's in the well, to have thrust upward from where it was installed, up through the well bore, out to the rig, out from the rig and onto the deck of this vessel I think is an indication of the magnitude of this catastrophe," Newman told the U.S. House Transportation Committee.

Newman also said that a blowout preventer, which is a last-resort mechanism to shear off a well in the event of a catastrophic pressure surge, had been "fully tested," most recently on April 10 and April 17. But he said that those tests didn't occur in the presence of the Coast Guard or the Interior Department's Minerals Management Service.

"Those tests are conducted by Transocean under the watchful eye of BP," Newman said. He said that regulators "aren't present on the rig when those tests are conducted." 


___________________________________________________________________________________


 

 

Update May 27th 2010
BP Internal Investigation Memo


I received this document in email this morning dated May 25th which describes  indicators the well was flowing  several times before the actual blowout. You can read the entire BP Memo Here

New Photos of Activity on Gulf of Mexico Location