Largest Manifold for Phase II of Deep Sea No. 1 Installed

Date：2024-04-12

On April 9, it was learned that the three sets of deep-water underwater central manifolds for the Phase II of Deep Sea No. 1 Gas Field project contracted by Offshore Oil Engineering Co., Ltd. (COOEC), with the largest weight and most complex structures, have been successfully installed. This marks the first application of China National Offshore Oil Corporation's independently developed deep-water multifunctional underwater manifold system in the development of deep-water high-temperature and high-pressure oil and gas reservoirs.

 

The Phase II of Deep Sea No. 1 Gas Field project is located approximately 132 kilometers from Sanya, with a distance of about 70 kilometers from the Deep Sea No. 1 Energy Station. It is China's first deep-water high-pressure gas field project, with proven OGIP exceeding 50 billion cubic meters. With the maximum operating water depth is nearly one kilometer, the project is equipped with 12 underwater gas wells and a new deep-water underwater production system.

 

The underwater works of Phase II of the Deep Sea No. 1 Gas Field project involve three sets of underwater central manifolds, with a combined weight exceeding 540 tons. The first and second sets were respectively installed at the end of last year and the beginning of this year. The third set of underwater central manifold (south manifold) installed in this operation will be connected to seven underwater gas wells. It is the largest underwater structure in the project, with a lifting weight of 187 tons. The installation was carried out by China's first 3000-meter deep-water multifunctional engineering ship, the “HYSY 286” ship.

 

For this installation, the project team from COOEC repeatedly optimized the construction plan, pioneering a mode featuring "underwater production system + shallow water jacket treatment platform + deep-water semi-submersible platform remote control system". They succeeded in overcoming several technical challenges, including wire rope twisting during ultra-deepwater engineering operations, and also registered a new record for the depth of dual-rope lifting operations in China's offshore engineering at 960 meters.