On February 28, CNOOC announced that with the last module hoisted into place, the offshore installation operations of the second phase of the "Shenhai No. 1" comprehensive processing platform were completed, marking the first "four-star continuous" offshore natural gas project in the southern waters of my country. The field production cluster was successfully established.
The comprehensive processing platform of the second phase of the "Deep Sea One" project is located in the waters of Yacheng, Hainan, about 90 kilometers away from Sanya City. It consists of a lower jacket and an upper production facility. The total height is about 136 meters, which is equivalent to the height of a nearly 49-story residential building. It weighs more than 14,000 tons, equivalent to the weight of more than 9,000 cars.
The total weight of the upper production facilities completed this time is more than 7,500 tons, and the projected area of the deck is equivalent to the size of five standard basketball courts.
The "base" of the jacket with a height of more than 100 meters has been installed in advance on the seabed nearly 90 meters deep, and driven 105 meters below the seabed through 12 steel piles to ensure that this "sea giant" can withstand strong typhoons. Stable as a mountain.
"During the construction period, the northeast monsoon prevailed, and the sea current speed was more than three times greater than that in normal sea areas. We invested in the country's largest offshore oil and gas engineering crane ship 'Blue Whale 7500', and adopted various measures such as flow speed monitoring and early warning, precise guidance and position limiting, to overcome the harsh sea conditions. Lifting technical difficulties ensure that offshore hoisting is completed safely and with high quality, and the positioning accuracy is required to reach the millimeter level." Guo Qing, general contracting project manager of the second phase of the "Deep Sea No. 1" project of CNOOC Offshore Oil Engineering, said.
Hoisting is the most commonly used installation method for offshore oil and gas platforms. It lifts and accurately installs offshore platforms weighing thousands of tons to the designed position on rough seas in a way similar to a weightlifter's "snatch". The construction process is affected by The influence of multiple complex factors such as ocean currents, swells, and wind forces imposes high requirements on the accuracy of design calculations, ship stability, and hoisting technology.
According to Liu Kang, CNOOC’s “Deep Sea One” Phase II project manager, the successfully installed “Deep Sea One” second phase comprehensive processing platform is a key facility for receiving and processing deepwater oil and gas. It is jointly used with the Yacheng gas field production platform. The "four-star connected" offshore natural gas production cluster will become a central hub for offshore natural gas processing and gathering and transportation in my country's southern waters, laying a more solid foundation for further improving my country's offshore natural gas production capacity.
The "Shenhai No. 1" ultra-deepwater gas field was put into operation in June 2021. The proven geological reserves of natural gas exceed 100 billion cubic meters. It is the deepest offshore ultra-deepwater gas field independently developed by China and the most difficult to explore and develop.
After the second phase of the "Shenhai No. 1" project is fully put into operation, the reserves of the "Shenhai No. 1" ultra-deepwater gas field will be increased from 100 billion cubic meters to 150 billion cubic meters, and the annual output will be increased from 3 billion cubic meters to 4.5 billion cubic meters.
(The video of Liu Shijiong produced by reporter Wang Enbo is sourced from CNOOC)
Editor in charge: [Lu Yan]