On June 8, according to the official news of CNOOC, the central processing platform of Kenli 10-2 Oilfield Group Development Project (Phase I) of the 100-million-ton oilfield group in the Bohai Sea successfully completed the installation of offshore floats, breaking the record of the size and weight of the oil and gas platform in the Bohai Sea region, and laying the foundation for increasing reserves and production of China's largest crude oil production base.

The largest oil and gas platform in the Bohai Sea has completed the installation of offshore floats

Kenli 10-2 Oilfield Center Processing Platform is a 3-storey 8-legged multi-functional offshore platform integrating production and life, with a height of 22.8 meters, a projection area equivalent to the size of nearly 15 standard basketball courts, and a design weight of more than 20,000 tons, which is the largest in the Bohai Sea in terms of weight and size. Because the weight far exceeds the limit of the domestic offshore floating crane capacity, the builder adopts the floating support method for construction, that is, with the help of the natural force of the tide rise and fall, the offshore part of the platform is accurately installed on the jacket standing in the sea in a way similar to the "clean and jerk" of weightlifters.

Shen Liang, Project Manager of Kenli 10-2 of CNOOC Engineering: The project team applied digital twin technology for 3D modeling and calculation analysis, repeatedly optimized the construction plan through simulation rehearsal, and equipped 3 sets of Beidou positioning systems with artificial intelligence algorithms on the main operation ship "Haiyang Shiyou 228", and at the same time cooperated with multiple tugboats to achieve a precise installation in place.

In this installation, the 20,000-ton platform allows the main operation ship to have a draft of 12 meters, and the bottom of the ship is only 1.7 meters away from the underwater structure, and in the rough sea, the main operation ship with a total length of nearly 200 meters has to sail under the wind and waves between the jacket legs with only 10 centimeters of clearance on each side, which is as difficult as the docking of a spacecraft and the space station.

Ma Jinxiong, installation manager of Kenli 10-2 project of CNOOC Engineering: We accurately monitor the sea state information, set up multiple sets of "millimeter-level anti-collision radars" on the construction ships, and apply self-designed new fender systems and pile leg coupling buffers and other protection devices, and successfully control the docking accuracy of the 8 plug tips and pile legs within 5 mm.

The platform has entered the commissioning stage and is expected to be put into production within the year

Kenli 10-2 Oilfield is the largest lithologic oilfield discovered offshore in China so far, with regional proven geological reserves of more than 100 million tons of crude oil, after the installation of the central processing platform is completed, it will enter the commissioning stage and is expected to be put into production within the year, which will inject new kinetic energy into the Bohai Oilfield to achieve 40 million tons of oil and gas production in 2025, and further enhance the energy supply capacity of Beijing-Tianjin-Hebei and the Bohai Rim region.

The total weight exceeded 600,000 tons, and China's float installation technology has reached the world-class level

The installation of giant equipment has always been a major challenge in the field of offshore engineering construction. In recent years, with the acceleration of the pace of advancing into the deep sea, the installation technology of floating support for China's large-scale offshore oil and gas platforms has reached the world's advanced level.

There are two main ways to install offshore oil and gas platforms: offshore hoisting and floating installation. Offshore hoisting is completed by a lifting vessel with offshore floating capacity, which is subject to the ship's hoisting capacity and safety risks, and is usually used for the installation of offshore platforms below 8,000 tons.

The core of the offshore float installation technology is to use the natural force of the tide and the construction technology such as ship loading, through a way similar to the "clean and jerk" of weightlifters, when the tide is high, the offshore block of the barge consignment platform sails into the jacket notch that has been installed in the sea, and the offshore block falls accurately from a high position to the predetermined position of the jacket at low tide, and the ship is withdrawn to complete the installation after the load transfer is completed, which has the advantages of large installation weight and short construction period.

Up to now, China has completed the installation of 50 large-scale offshore platform floats, with a total weight of more than 600,000 tons, more than 14 "Bird's Nest" national stadium steel structure weight, and has overcome the key technologies of all-weather, full-sequence and all-sea floats such as high, low, dynamic positioning, and double floats, and has established a technical system with complete independent intellectual property rights.(This article is from the official website of Seetao www.seetao.com. Reprinting without permission is strictly prohibited. Please indicate Seetao.com + original link when reprinting) Seetao.com Strategy Column Editor/Sun Fengjuan