On November 21, CNOOC announced that China's independently designed and built deepwater jacket "Hai Ji No. 2" was successfully capped in Zhuhai, Guangdong. Its completion set two new Asian records for height and weight at once, and is of great significance for further enhancing China's independent design and construction capability for ultra-large deepwater offshore oil and gas equipment.

According to reports, the jacket is equivalent to the "foundation" of a fixed offshore oil and gas platform, used to support the platform's huge body and enormous tonnage. The "Hai Ji No. 2" jacket has a total height of 338 meters, exceeding the height of the main tower of Beijing's China World Trade Center Phase III, and weighs 37,000 tons; the steel used is close to the total weight of the steel structure of the National Stadium "Bird's Nest." Both its height and weight are currently the greatest in Asia.

"Hai Ji No. 2" is located in a typhoon-prone area with harsh sea conditions and huge wind waves and internal solitary waves. As water depth increases, the technical difficulty of designing and building ultra-large offshore engineering structures that bear environmental loads of over ten thousand tons increases sharply. The giant "tonnage" of "Hai Ji No. 2" is already approaching the load-bearing and lifting equipment capacity limits of domestic construction sites. The resulting challenges—including foundation settlement, complex force calculations, large-scale lifting, and precision control—have all reached the highest level for domestic fixed offshore platforms.

According to Wang Minfeng, project manager for the construction of CNOOC's "Hai Ji No. 2," the project used S420 high-strength steel on a large scale for the first time in the construction of a jacket platform in China, greatly reducing the total structural weight while improving strength. It overcame technical difficulties such as the independent design of ultra-large deepwater jackets, the joint lifting of ultra-heavy structures, and the independent development of high-strength steel welding processes, placing it at the forefront of Asia in the field of design and construction technology for jacket platforms in water depths of more than 300 meters.