Haiji-1, Asia’s largest jacket with a length of 302 meters and a weight of more than 30000 tons, successfully slipped and launched in the sea area of Lufeng oilfield, creating a new Asian record for the launching of deep-water jackets, marking that the complete set of key technologies and installation capacity of China’s super large deep-water jackets have reached the world-class level, which is of great strategic significance for promoting China’s offshore oil and gas storage and production and ensuring national energy security.
The water part of “haiji-1” extends more than 80 meters out of the barge and enters the water for less than 1 minute. It is difficult to complete all data monitoring and recovery of sliding launching in such a short time. Since receiving the task of monitoring the launching dynamic process of “haiji-1” jacket in early January this year, the measured members of the ocean engineering team of Jiaotong University have been busy. In order to obtain the most accurate data, the scientific research team should not only monitor the huge jacket itself, but also monitor the position and attitude of the launching barge at the same time, so as to restore the whole process of actual sliding launching.
“We have developed a self-contained motion acquisition silo and a structural stress slip monitoring system to realize the complete measurement of the attitude of the jacket and barge and the dynamic load of the key structure of the jacket.” Researcher Li Xin, the person in charge of the project, said. In order to ensure the complete monitoring of the whole launching process information by the high-precision satellite positioning signal, the monitoring system needs to run through the entire 302 meter long jacket. The team solved the problem of long-distance GPS monitoring signal transmission, and ensured the high reliability of the whole system and the accuracy of data monitoring.
Facing the complex offshore operation environment, the team designed a comprehensive monitoring scheme of multi-source information verification and mutual backup to ensure the reliability of the monitoring scheme and the credibility of the monitoring results. It also developed unmanned and remote monitoring technology to realize the linkage mode of onshore remote commissioning and rapid start of offshore equipment. With the successful recovery of all monitoring equipment, the measured task was a complete success.
This is the first time that China has obtained the measured data of launching trajectory of 300m ultra deep jacket, which indicates that China has mastered the “core password” of numerical analysis of launching process of deep-water jacket. With the continuous advancement of China’s deep-water development process, deeper and larger jackets have been built. The valuable measured data will provide solid data support for the innovative design, safe operation and design software verification of deeper water jacket platform. (CCTV reporter Wang Dianjia)