A CNOOC LNG tanker is seen off Hainan province in September 2020. [Photo provided to China Daily]

CNOOC banks on in-house deepwater jacket for super large drilling platform

Asia's first 300-meter deepwater jacket, designed and built independently by China National Offshore Oil Corp, completed construction on Monday in Zhuhai, Guangdong province, marking a major breakthrough in the jacket design and a milestone in the construction of a super large offshore oil and gas platform in China.

The jacket, named Haiji One, is expected to be installed in late March. It will serve its Lufeng 15-1 oil field platform located in the South China Sea. When put into operation in September, it will further improve the country's energy supply and guarantee China's energy security, said its operator CNOOC, the country's top offshore oil and gas driller.

A jacket serves as the foundation of the offshore oil and gas platform. Used to support the huge body and tonnage of an offshore platform, it is the most widely used offshore oil and gas development equipment globally.

An analyst said the project will also safeguard energy supply throughout the Guangdong-Hong Kong-Macao Greater Bay Area.

Li Ziyue, an analyst with BloombergNEF, said China has seen continuous upstream investment and production commitment in recent years, while stepping up domestic oil and gas production with significant offshore results. She believes China's offshore oil and gas production has great upside potential and is expected to continue rising during the next few years.

CNOOC's oil and gas production is expected to rise more than 6 percent each year during the 2022-24 period, playing a critical role in enhancing the country's energy supply security, Li said.

Haiji One is located in waters that are around 284 meters deep and this is the first time that a jacket featuring China-design, China-construction and China-fix is seen in waters of this depth, said Gao Shuang, project manager of the Lufeng oilfield.

Among thousands of jackets production platforms worldwide, only 10 of them are located in waters more than 280 meters deep, CNOOC said.

The facility will further facilitate the exploration of the Lufeng oilfield, which is expected to reach an annual crude output of 1.85 million metric tons when put into operation, it said.

The Lufeng 15-1 jacket is located in a typhoon-prone area, with harsh sea conditions, huge winds and large waves.

It also faces world-class marine engineering problems, including large movable sand waves. CNOOC has innovatively proposed a 300-meter-class deepwater jacket design and construction plan. It has conquered various challenges, including the overall design of super large jackets, the combined hoisting of large-size, large-span, and large-tonnage structures with multiple cranes and the size control of super-large structures, it said.