A 1.2 billion dollar tilt

Working on a tight schedule, across continents and divisions, Wärtsilä salvaged both the sunken rig, Odfjell’s Deepsea Aberdeen, and a billion-dollar contract. Along the way, the team learned the value of mud.

At the tail end of a year full of hard work, Simen Lieungh, Odfjell Drilling's CEO, was at ease in his mountain cabin in Norway when some bad news disrupted the scene. Over the phone, he was told that Deepsea Aberdeen, a sixth-generation ultra-deep and harsh-environment rig his company was putting together for BP, had sunk in its South Korean bay. “It’s the kind of phone call you just don’t want to get,” Lieungh says. By the following Monday, shares in Odfjell Drilling had dropped by over 2 percent.

It was a worker on board Deepsea Aberdeen who, instructed to drain a tank of water in a submerged part of the rig, instead opened a manhole that lead directly into the Korea Strait. Water gushed into the hull and spread quickly since the construction, still incomplete, had several sections open inside.

Scores of personnel quickly abandoned the drilling rig, with no injuries reported. As they watched from the dock, one end of the rig began to tilt towards the blue sky. The other sank to the seabed.

As a provider of key equipment to the rig, Wärtsilä was in the thick of a crisis that was as serious as it was unexpected. “I was totally surprised that it could happen,” says Matias Karls, general manager of Wärtsilä Ship Power's North Asia Sales division. In the 16 years he had then spent at Wärtsilä, nothing as severe had happened before.

Within a week, with the rig still on the seabed, Wärtsilä’s project manager Dong Hwan Kim arrived on Geoje Island alongside service engineers to assess the damage.

Wärtsilä had provided the rig with eight thrusters and eight diesel generators. The thrusters—propellers installed on the underside of the pontoons to help the rig maneuver and keep its position at sea—were thought to have taken the worst hit when the rig hit the seabed.

The sunken rig was already under a seven-year contract with BP, with drilling scheduled to begin in the West Shetlands in the late summer of 2014. The accident put the deal—the largest in Odfjell Drilling's 40-year history—in jeopardy, and 1.2 billion dollars now hung in the balance.

For each day that the delivery of the rig was pushed back, the company stood to lose over 450,000 dollars in revenue. “In the worst case, this could have meant a loss of the contract,” says Simen.

It was on Wärtsilä to come up with a solution.

Installing new thrusters would delay the delivery of the rig by close to a year. That wasn't the kind of schedule Odfjell Drilling and the local shipyard had in mind. “They needed the rig operational as soon as possible and could not accept the lead time of new thrusters,” says Matias. “Repair was the only option that might meet their time schedule.” Wärtsilä had to deliver the thrusters by the end of July. 

In late January, a month after the incident, the on-site manufacturer brought the platform afloat again. Ten days later, divers carried out an underwater inspection that would reveal the true extent of the rescue operation. It all depended on the condition of the seabed.

"If you have a hard bottom, then all the weight of the rig is coming down on the thruster," says Pieter Eelman, commissioning coordinator at Wärtsilä's Delivery Management Field Service, who oversaw the repair operation from his base in the Netherlands. "The nozzle and the steering pipe will be deformed." The inspection results showed that the Korean seabed had proven Odfjell Drilling’s saviour by cushioning the impact.

“Because of the layer of mud, which was maybe 10 metres deep or more, the weight of the rig was absorbed not by the thrusters but by the rig itself,” said Eelman. “Everybody was very happy that the seabed was soft.”

While there was limited external damage to the thrusters, Eelman says, there was a lot of sea water inside of them. “We expected water inside the thruster, but not this much.” The underwater demountable thrusters were taken to a workshop near the Korean yard, where they were dismantled into pieces that would fit onto a plane to Europe. "Only the critical parts were sent, essentially the propeller gearbox and stem section of the thrusters." Other parts, like the nozzles and the propellers, stayed in Korea.

So far, the operation was on track. But Wärtsilä had only about three months to complete repairs on eight thrusters that had suffered significant damage.

“The thrusters were now filled with a mixture of oil and water,” Pieter says. As oil is less dense than water, it floated on top of the seawater, which went into the gear sets themselves. Replacing the gear sets would have meant a six- to eight-month wait. Instead our supplier in Finland was able to repair the gear sets and send them back to the Netherlands. “it was imperative to recondition the gear sets without replacing them,” says Pieter.

Then there was the question of repairing the rest of the thrusters. To save time, the Wärtsilä team decided to split the work on the repairs in half and deliver four propellers to Wärtsilä’s Propulsion Workshop in Schiedam, outside of Rotterdam in the Netherlands, and four to our thruster and engine production plant in Trieste, italy.

While pressed for time, we could serve all of Odfjell’s needs within the huge company as ship power and services collaborated closely. As it turned out, the quickest way to repair a platform under construction in South Korea was to spread the parts over Europe.

“It was very important [to split the work in half] to meet the delivery time we had set,” says Pieter. Since Trieste specializes in manufacturing thrusters, and their Schiedam colleagues in repairing them, the two sites worked in close cooperation during the spring.

In mid-June, Wärtsilä began sending back the parts to the shipyard in South Korea. The sea trial was concluded in early September to make the scheduled delivery date of 10 October.

Deepsea Aberdeen—Odfjell's crown jewel, custom-made for BP to honour the largest contract in the company's history—has been saved. “The financial impact wasn't too big,” says Ivar Andreas Lemmechen Gjul, an analyst at the Norwegian investment bank Fondsfinans. “It was the best outcome in a worst-case scenario.” 

The rig will start drilling in the first quarter of 2015, delayed by five months. “When we started this recovery work, everybody doubted whether Wärtsilä could achieve it within the required time frame and with the quality we promised,” says Kim, whose team ensured that the on-board disaster did not, in the end, jeopardize the contract with BP.

And their work has not gone unnoticed. This spring, Simen Lieungh, Odfjell Drilling's CEO, spoke at Wärtsilä's customer conference and was eager to praise us. “We really felt that Wärtsilä did absolutely everything to make sure we got the quickest service and great quality,” Simen says, with the delivery of the rig only weeks away.

“Odfjell are one of our key customers,” says Cato Esperø, sales director at Wärtsilä Norway. “We are very happy that [Simen] is happy with the performance. That's what we're working on all the time: to deliver a quality product in the best possible way.”
© 2018 Wärtsilä