深水钻井钻柱疲劳寿命研究

摘要

Dynamic response of the deepwater drilling platform increases alternating loads of the drilling string�As a consequence, the calculation of drill string fatigue life becomes more complicated�By using the numeri⁃cal simulation method, a method for studying drill string fatigue life is proposed based on AQWA module, transi⁃ent dynamic analysis module and fatigue analysis module of Ansys⁃Workbench�A case study was conducted to ob⁃tain motion response of some marine platform and further get the drill string fatigue life of about 102�61 d�Calculation results show that the drill string serving up to 100 days must have flaw detection to determine whether it can continue to run in the deepwater drilling operation up to 1 000 m�In particular, great attention should be paid to the drilling string near the surface.%深水钻井作业中平台的动力响应将使钻柱承受更多的交变载荷，钻柱疲劳寿命的计算过程更为复杂。应用数值模拟方法，通过Ansys⁃Workbench中的AQWA模块、瞬态动力学分析模块以及疲劳分析模块，提出了一种研究深水钻井中钻柱疲劳寿命问题的方法。通过实例计算，得到了某海洋环境下平台的运动响应，进而得到钻柱的疲劳极限寿命约102�61 d。计算结果表明，对于水深1000 m的深水钻井作业，服役时间达到100 d的钻柱必须经过探伤检测，方能确定是否继续使用，且尤其应注意靠近水面部分的钻柱。