台风作用下锚泊定位半潜式钻井平台动力特性研究

The Dynamic Characteristics of Mooring Semi-Submersible Drilling Platform in Typhoon

刘正礼 张浩 阳文学 张玉亭 畅元江

Liu Zhengli Zhang Hao Yang Wenxue Zhang Yuting Chang Yuanjiang

中海石油(中国)有限公司深圳分公司, 广东深圳 518067; 中国石油大学(华东)海洋油气装备与安全技术研究中心, 山东青岛 266580

Shenzhen Branch of CNOOC, Shenzhen, Guangdong, 518067, China; Research Center for Offshore Engineering and Safety Technology, China University of Petroleum (Huadong), Qingdao, Shandong, 266580, China

南海台风活动频繁,严重影响着锚泊定位半潜式钻井平台的作业安全。采用水动力学计算软件 ANSYS-AQWA,基于三维势流理论和莫里森方程,建立了平台-锚泊系统耦合动力分析模型,开展了台风作用下的平台漂移分析和锚泊系统安全性评估。分析结果表明:当锚泊系统完整时,平台的平均漂移量与最大漂移量均超出API规定的许用值,需停止钻井作业并准备解脱,但锚链不会发生断裂。如果锚泊系统中安全系数最小的锚链发生断裂,平台的漂移量明显增大,锚泊系统最小安全系数明显减小,局部情况下锚链易相继断裂并造成连锁反应。研究表明,提出的相关方法和得出的结论可为极端天气下锚泊定位浮式装置的安全评估提供参考。

Frequent typhoons in the South China Sea may significantly affect safety of the operations on semi-submersible drilling platforms with anchor mooring system. By useing hydrodynamic calculation software, ANSYS-AQWA, the coupled dynamic analysis model for the platform-mooring system was established, and an analysis on the drift of semi-submersible platforms and the safety assessment of anchoring system were conducted based on three dimensional potential flow theory and Morison equation. The analysis results showed that when the mooring system was intact, both the average and maximum drift distances of platforms exceeded the allowable values specified in API. Under such circumstances, drilling operations should be suspended and a disconnection between the drilling riser and the wellhead should be done, if the anchor chain does not part. when the anchor chain of the least safety factor in the mooring system parted, the drift distance increased significantly, the minimum safety factor of the mooring system decreased obviously and in some cases, other anchor chains then parted in succession, leading to chain reactions. Research results showed that the proposed methods and the obtained conclusions could provide a reference for security assessment of mooring floating structures in extreme weather conditions.

国家重点基础研究发展计划("973"计划)项目"海洋深水油气安全高效钻完井基础研究"(编号:2015CB251200)、中海石油深海开发有限公司项目"深水半潜式平台锚泊系统安全评估与作业管理研究"(编号:YXKY-ZY-2014-SHENHAI-03)资助。

https://doi.org/10.11911/syztjs.201504007