Showing posts with label blow out preventer. Show all posts
Showing posts with label blow out preventer. Show all posts

Tuesday, February 26, 2013

Toasting BP

Lawyers have been submitting plenty of billable hours in the three years since BP's well blew in the Gulf of Mexico.  Today they are actually in court, making arguments to a jury.  One thing the delay has done is allow time for people to forget what happened. 
  Let's do a little review.  The BP well was drilled 13000 feet into a high pressure gas and oil deposit.  For some reason BP decided not to bring the well into production.  Instead BP tried to shut it down.  They pumped cement between  the drill pipe and the rocky hole to seal it.  After the cement was given enough time to harden, pressure readings indicated that the cement job was leaking.  Donald Vidrene and Robert Kaluza, two BP executives aboard the drill rig, ordered the readings ignored and to proceed to pump out the drilling mud.  Personnel from Trans Ocean (rig owner) and Halliburton (cement contractor) protested, saying the well was leaking high pressure natural gas.   The BP men ignored this advice and continued to pump out the mud and replace it with sea water.  The mud is very heavy and a 5000 foot column of mud is enough to contain the gas.  Seawater is much lighter and cannot withstand gas pressure.  The highly flammable natural gas, under great pressure, forced its way all the way up the drill pipe out onto the drill rig and ignited.  The resulting fires and explosions sank the rig and killed 11 workers.   Mr Vidren and Mr. Kaluza took the fifth amendment to avoid testifying at the inquiry, and then fled the country.
   An attempt was made to close the blow out preventer, a 500 ton valve on the sea floor to shut off the drill pipe.  This attempt failed.  Better than a year later, the blow out preventer was salvaged from the sea floor and brought up to a dock.  Engineers reported that the drill pipe was off center which prevented the rams from closing the pipe off.  That's a major design failure of the blow out preventer.. 
  The root cause of the accident is the decision by the BP executives on the rig to ignore indications of a leak and pump out the drilling mud.  The failure of the blow out preventer is a secondary issue, apparently that design is an industry standard.  I won't fault BP for using an approved industry standard device, even it failed to work. 
   The above information is from the Wall St. Journal, the only paper to cover the accident.  The rest of the MSM were conspicuous by their absence.