水下井口头疲劳寿命分析

在海洋钻井和生产过程中,水下井口头系统作为钻井和生产设施的基础装备,其疲劳寿命相当重要。以“勘探三号”平台为假设作业平台,以南海某油田海域作为工程实例取值,应用MOSES软件建立隔水管力学计算MOSES模型,得到求解出隔水管下端挠性接头受到的作用力;然后应用ABAQUS有限元分析软件ABAQUS建立水下井口头的有限元模型,根据研究海域土壤P-y曲线线性化,采用ABAQUS非线性弹簧模拟了土壤与水下井口头的相互作用,对水下井口头进行了疲劳寿命计算。计算结果表明,其疲劳寿命满足相关规范和DNV有关水下井口头的设计和使用要求。

Fatigue Life Analysis of the Subsea Wellhead

In the process of offshore drilling and production, the subsea wellhead system is the basis for drilling and production facilities and equipments. Its fatigue life is quite important. With "KAN TAN 3" platform as the hypothetical platform, taking some oilfeld in the South China Sea as an engineering example, the mechanical analysis model of riser was completed using software MOSES, and the force of flexible joint at the bottom of riser was calculated. Then ABAQUS fnite element analysis software ABAQUS was used to establish the fnite element model of the subsea wellhead system. The interaction between soil and subsea wellhead system was simulated based on the nonlinear spring of ABAQUS according to the P-y curve of the soil in the study area, and its fatigue life was calculated. The results show that fatigue life of the designed subsea wellhead can meet relevant specifcations and design and application requirements on the subsea wellhead of DNV codes.