Deepwater Horizon Blowout Preventer Failed on Design Flaw

(Image Courtesy WSJ)

In a report released Wednesday on the failure of the Deepwater Horizon blowout preventer, engineers hired by U.S. investigators (Norwegian risk-management company Det Norske Veritas) say the force of the blowout bent the drill pipe, knocking it off-center and jamming the shears. Rather than seal the well, the blades got stuck 1.4 inches or less apart, leaving plenty of space for 4.9 million barrels of oil to leak out. The investigators concluded the blowout preventer failed as a result of a design flaw, not because of misuse by BP or any of the other companies involved, and not because of poor maintenance. The fail-safe device, the last line of defense against a disaster, wasn't designed to handle a real-world blowout, according to investigators, who called for further study of the devices.

Even if the device had worked, it wouldn't have saved the lives of the 11 rig workers killed in the accident. That's because no one even tried to activate the shears until after massive explosions killed the men and crippled the rig. But the device could have mostly prevented the oil spill that began when the Deepwater Horizon sank two days after the initial explosion.

The blowout preventer was owned and maintained by rig owner Transocean Ltd. and built by Cameron International Corp. The report could turn attention to Cameron, manufacturer of the device.  (WSJ, 3/24/2011)