[BITList] dnv - uncertain?

[x50type at cox.net]

reports sounds ify to me......................................
lawyers are going to have a field day over this!
ct


      Uncertainties emerge in blowout preventer examination
      Published: Monday, April 04, 2011, 4:13 PM     Updated: Monday, April 04, 2011, 4:20 PM
       By David Hammer, The Times-Picayune 
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      The examination of the blowout preventer that failed to stop last year's massive BP oil spill left many important questions unanswered, the lead investigator testified Monday.

      View full sizeTimes-Picayune archiveThe BP blowout preventer was lashed to a barge docked at the NASA Michoud Assembly Facility in eastern New Orleans in September. 
      Det Norske Veritas is the Norwegian firm hired by the U.S. government to perform an autopsy on the blowout preventer recovered from the site of the largest oil spill in American history.

      Almost two weeks ago, Det Norske Veritas released a technical forensic report that primarily blamed the failure of the massive stack of closing valves and cutting rams on an unanticipated deflection of the drill pipe through which oil and natural gas began spewing last April 20.

      The key to that conclusion was a model showing the drill pipe stuck at two pivot points, one at the top of the four-story-tall blowout preventer and another near the bottom. The bowing of the pipe prevented the BOP's last-ditch mechanism, the blind shear rams, from properly cutting and sealing off the flowing pipe.

      But in testimony Monday, lead forensic investigator Greg Kenney said his team didn't have time to disassemble and review the valves that got the pipe stuck in the first place. Some previous testimony by rig workers indicated that the annular valve at the top of the BOP was open when the blowout happened, but the Det Norske Veritas report assumes it was closed, helping create a bow in the pipe that industry experts had never prepared for.

      And yet, the evidence recovered from the BOP showed no physical signs of any bowed pipe. Kenney said the assumption that the pipe did bow was based on computer models. Det Norske Veritas' project manager, Neil Thompson, said the pipe was found straight because it was elastic and returned to its natural position some time after the event.  ..........................................[Really? – ct]

      But Thompson also testified that the pipe was placed in the wrong position on a picture of one of the models used to determine what might have happened, adding again to the uncertainties in the Det Norske Veritas report.

      Another important uncertainty was when the blind shear rams actually attempted to cut the pipe. Det Norske Veritas tested a 27-volt battery that controlled what should have been an automatic trigger of the blind shear rams moments after the accident, and found it had just 7 volts of charge in June and 0.7 volts of charge in September.

      Based on that, Kenney and Thompson concluded the automatic trigger of the shear rams probably failed, meaning it likely took until two days after the accident for remote-controlled submarines to activate the rams. But they also said it was possible that a backup control pod worked in the minutes after the blowout and succeeded in triggering the blind shear rams.

      That is an important distinction because it could mean that rig-owner Transocean didn't properly maintain the BOP and that might have contributed to the accident. Transocean witnesses who were scheduled to testify Tuesday have refused to show up and could not be compelled to do so because they live out of the area, where the federal subpoenas served against them from New Orleans have no power.

      That has caused the Marine Board of Investigation to cancel its hearing scheduled for Tuesday and resume testimony Wednesday.








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