Construction on the world's biggest ultra deepwater semi-submersible drilling rig with dual drilling towers began last week in Yantai, East China's Shandong province.

Yantai CIMC Raffles Offshore Ltd Co, China's leading offshore engineering manufacturer and a subsidiary of the China International Marine Containers Group, is building the drilling rig, called Frigstad D90, for Norway's Frigstad Deepwater Co.

The Frigstad D90 has an overall length of 117 meters, a width of 92.7 meters and a height of 118 meters. It is designed to have a maximum vertical drilling depth of 15,250 meters, according to the builder.

As one of the seventh generation of ultra deepwater semi-submersible drilling rigs, it is equipped with DP3 dynamic positioning system and has adopted the latest technologies to improve safety and production efficiency.

It is scheduled to be delivered by 2015 and is designed for operation in deep water areas around the world, such as the Mexico Gulf, South China Sea, and South Atlantic.

"CIMC Raffles has rich experience in the construction of drilling rigs and enjoys a good reputation for its product quality and delivery performance. This is the reason why we chose to continue cooperation with the company," said Harald Frigstad, executive director of Frigstad Deepwater Co, at a launch ceremony for the project on Aug 28.

He said it is the second deepwater semi-submersible drilling rig that Frigstad Deepwater Co has ordered from CIMC Raffles.

The first one, named SS Frigstad Oslo, has been performing well in sea areas of Cuba, Brazil and the United States and has completed four wells with no accidents since its completion in 2010.

"The new project, Frigstad D90, is the largest, most powerful and most advanced rig of its kind ever to be built in the world. This is something that CIMC Raffles can be proud of," he said.

He added that with its advantages in terms of cost as well as high production efficiency and a large number of marine engineering professionals, China is likely to gain a leading position in the offshore rig-building industry worldwide.

"We believe that will happen, and China will be the best place for us to find a good partner," Frigstad said.

According to a medium to long-term marine equipment industry development plan issued by the central government in March 2012, China will boost its share of the global offshore equipment industry to 20 percent by 2015 and to 35 percent by 2020. It was less than 8 percent in 2011.

China will also nurture five to six world-class companies that are set to have annual revenue of 40 billion yuan each by 2020.

"With more than 40 years' experience in marine equipment manufacturing and about 800 researchers and engineers, we are striving to become one of the world's leading offshore rig builders in the near future," said Yu Ya, president of CIMC Raffles.

The company has delivered all kinds of giant rigs, including six semi-submersible drilling platforms as well as numerous pipe-laying vessels and self-elevating drilling units. Another three semi-submersible drilling platforms are now under construction, Yu said.

wangqian2@chinadaily.com.cn

By Wang Qian