海洋水下钻井井口疲劳损伤性能设计方法  

Design method for fatigue damage performance of offshore underwater drilling wellhead

作　　者：刘书杰 李文拓 徐一龙 刘正 李清平 李君 曾春珉 Liu Shujie;Li Wentuo;Xu Yilong;Liu Zheng;Li Qingping;Li Jun;Zeng Chunmin(CNOOC Hainan Energy Co.,Ltd,Haikou 570100;CNOOC Research Institute Co.,Ltd,Beijing 100028;Hainan Branch of CNOOC(China)Co.,Ltd,Haikou 570100;Hainan Province Key Laboratory of Deep Sea Energy Engineering,Haikou 570100)

机构地区：[1]中海油海南能源有限公司,海南海口570100 [2]中海油研究总院有限责任公司,北京100028 [3]中海石油(中国)有限公司海南分公司,海南海口570100 [4]海南省深海深层能源工程重点实验室,海南海口570100

出　　处：《石化技术》2024年第9期114-116,共3页Petrochemical Industry Technology

基　　金：国家重点研发计划课题“多气合采复杂结构井钻井技术及装备”(课题编号:2021YFC2800904)。

摘　　要：水下钻井井口的疲劳分析是水下井口设计必须满足的基本要求之一。疲劳强度计算涉及在低于材料屈服极限的交变应力(或应变)的反复作用下,零件和构件在应力集中部位萌生裂纹,经过一定循环次数后裂纹扩展,最终突然断裂,这一失效过程称为疲劳破坏。材料在疲劳破坏前所经历的应力循环数称为疲劳寿命。双井口吸力桩的疲劳载荷来源于隔水管下部挠性接头的张力、剪力和弯矩的不断变化。波浪和洋流作用于平台和隔水管系统而引起的周期载荷被传递到底部挠性接头,经过挠性接头后载荷幅值大大减少。重点分析了隔水管的力学模型、不规则波浪载荷的模拟、结构动力响应以及疲劳损伤计算方法。研究结果为水下钻井设备的设计和操作提供了宝贵的见解。The fatigue analysis of the subsea wellhead is one of the fundamental requirements for the design of subsea wellheads.Fatigue strength calculation involves the initiation and propagation of cracks in areas of stress concentration under the repeated application of fluctuating stresses(or strains)below the material’s yield limit,leading to sudden fracture after a certain number of cycles,a process known as fatigue failure.The number of stress cycles a material withstands before fatigue failure is referred to as the fatigue life.In this study,the fatigue load of the dual wellhead suction pile originates from the varying tension,shear,and bending moments at the lower part of the riser’s flexible joint.The cyclic load caused by the action of waves and currents on the platform and riser system is transmitted to the lower flexible joint,where the load magnitude is significantly reduced.The transmitted load continues through the lower marine riser package(LMRP),the blowout preventer(BOP),and the wellhead system.This study focuses on the fatigue damage performance design method for subsea wellheads,analyzing the mechanics of the riser,simulating irregular wave loads,calculating structural dynamic responses,and applying fatigue damage calculation methods.The research concludes with a comprehensive understanding of the fatigue behavior of subsea wellhead systems,providing valuable insights for the design and operation of subsea drilling equipment.

关 键 词：水下井口 疲劳分析 吸力桩 动力响应 疲劳损伤计算 

分 类 号：TE951[石油与天然气工程—石油机械设备]