深水水下井口系统疲劳监测损伤评估研究进展

Research Progress of Fatigue Monitoring and Damage Assessment of Deepwater Subsea Wellhead

水下井口系统在钻完井和修井等连接作业过程中,受到波浪和海流引起的隔水管振动、平台运动以及作业性动载荷等传递而来的循环载荷作用,这些循环载荷使水下井口产生循环弯矩,导致水下井口疲劳损伤不断累积。为了促进深水水下井口系统技术进步,提高水下井口系统的安全利用水平,总结了深水水下井口系统特点,调研了水下井口在南海的应用现状和前景;分析了水下井口在损伤预测、疲劳监测、多源监测数据融合处理等疲劳损伤评估研究中的进展;总结了水下井口疲劳损伤评估研究难点,最后提出了水下井口疲劳损伤评估技术的发展方向及研究建议。水下井口疲劳损伤评估研究难点是水下井口疲劳监测水池试验待开展、缺乏多源监测数据融合的水下井口修正有限元模型。所得结论可为水下井口系统技术发展及深海应用提供参考。

The deepwater subsea wellhead system is subjected to various cyclic load during drilling, well completion and workover, attributed to the riser vibration and platform movement induced by ocean waves and currents, and dynamic load triggered by operations.Such cyclic loading results in the cyclic bending moment of the subsea wellhead and subsequently accumulated fatigue damage.In order to promote technical advancement and improve the application safety of deepwater subsea wellhead systems, the characteristics of subsea wellheads are summarized, and the application status and prospect of subsea wellheads in the South China Sea are investigated.The progress of subsea wellhead fatigue damage assessment and research is analyzed, including damage prediction, fatigue monitoring, and fusion and processing of multi-source data.The difficulties of subsea wellhead fatigue damage assessment and research are identified, and last, the development orientations and suggestions for the subsea wellhead fatigue damage assessment are proposed.The difficulties of investigating subsea wellhead fatigue damage are the undone tank test of subsea wellhead fatigue monitoring and the lack of corrected finite-element-method subsea wellhead models integrating multi-source monitoring data.The conclusions of this research provide references for the technical development and deepwater applications of subsea wellhead systems.