How to Lift 3,500 Tons
Stephen Zacks
at 02:04 AM Dec 21 2011
How to Lift 3,500 Tons
Strong Platform
Jack Thompson
Tech // 

Before Hurricane Ivan hit in 2004, hurricanes were rarely able to knock over any of the thousands of aging oil platforms in the Gulf of Mexico. A rig can withstand an 80-foot wave. But Ivan brought 100-foot peaks. So did Katrina and Rita. In the past seven years, the region's fiercest recorded hurricanes have torn down more than 200 rigs.

Even as a young engineer designing these platforms in the late 1970s, Jon Khachaturian saw it coming. The principles of designing them were fairly simple: Keep the rig broad enough to remain stable and tall enough to keep waves off the deck, because water on the deck will bend the platform right over. But, Khachaturian says, the industry standards for wave resistance were inadequate. "We were designing for what was considered the 100-year storm. I remember asking, ‘How do we know what a 100-year storm is? They've only been keeping records for 60 years.' "

Khachaturian went from designing rigs to designing ways to move them around. In 1981, after inventing a way to pick up an entire drilling platform from a single point using steel beams, he started his first company, Versabar. He was 26. Now, after 20 years, he holds 50 patents, employs 700 people in the Gulf region-and has changed his focus once again. Versabar still specialises in oil-rig installation, but it is also branching into another line: pulling wrecked oil platforms out of the ocean and bringing them to shore.

A drilling company cannot simply plug and abandon a derelict rig. The Bureau of Ocean Energy Management requires such platforms to be salvaged, and quickly. Any rig in U.S. territorial waters that becomes inoperable or runs out of oil must be removed within five years. And the life span of the average rig is no more than 25.

Until Khachaturian got into the business, salvage and removal was not just expensive, it was dangerous. Divers at depths of up to 500 feet had to hack the rigs into pieces small enough to be removed using conventional derricks. A gas pocket ignites, a diver exceeds his time limit, or a section of the rig falls in an unexpected direction when it's cut free, and somebody dies. (A massive manta ray once incapacitated a diver hundreds of feet down.) Those jobs take months. So Khachaturian built the VB10000, a 25-story arched truss on top of two 22-by-91 metre barges. The VB10000 can pull out an entire rig in a day, at one fourth the cost of a traditional salvage job.

In the past year, Khachaturian's monster has removed 30 platforms and salvaged roughly 70 in pieces. Another 25 sunken rigs are on the to-do list. And Khachaturian isn't convinced that we've even seen a 100-year storm yet. There are approximately 7,000 rigs operating in the Gulf of Mexico. They will all be retired eventually-if nature doesn't get to them first.

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