Han Ximin

ximhan@126.com

THE installation of China’s largest self-designed and constructed oil rig, Lufeng 14-4, was completed Tuesday, the China National Offshore Oil Corporation announced yesterday.

The oil rig is divided into two parts, the substructure for the drilling and the production platform and the topside above the sea.

The topside installation, which was completed within 13 hours, was carried out through the floatover method, by utilizing a launch barge to transport the topsides in one piece, position the vessel over the substructure, and lower the topsides onto the substructure while maintaining the position of the vessel. The deck for the eight-legged drilling and production platform weighs nearly 15,000 tons.

The oil rig is about 240 kilometers southeast of Shenzhen. It is about 218 meters in height with 145 meters submerged in the water. The total weight of the rig is 30,000 tons, three times the weight of Eiffel Tower.

The Lufeng 14-4 oil rig was constructed by the CNOOC’s Shenzhen Company and will be put into production before the end of this year. It will be deployed for the joint development of LF 14-4 and LF 14-8 fields in the Pearl River Mouth Basin.

“The floatover method is the most effective way to reduce work on the sea, is competitive in cost and efficiency and has been widely used for the installation of oil rigs at 10,000-ton or above levels,” explained Gao Shuang, general manager of the Lufeng Oil Fields Development Project.

The substructure for drilling and the production platform were built on shore at Shenzhen Chiwan Sembawang Engineering Co. Ltd. The eight-legged jacket with its 12 skirt piles, weighing around 15,000 tons, was installed in water depth of around 145 meters before the topside was mounted.

In 2020, the offshore gas and oil production in China reached 65 million tons. The production of oil increased by 2.4 million tons year on year.