深水钻井喷射法安装表层导管极限下入深度确定

摘要

Accurate calculating the limit depth of surface conductor has an important significance for the safe and efficient deep-water drilling. According to the stress analysis of the conductor jetting system, the soil parameters and construction parameters affecting the conductor setting depth ware studied. The soil parameter influence factors including soil strength and soil friction resistance, and the construction parameter influence factors including jetting pressure, displacement and verticality. Base on the study of the conduc-tor jetting system in total force balance conditions, a prediction model of conductor limit jetting depth in deepwater were established. An example calculated using the prediction model for the South China Sea actual deep well. The results show that the minimum and maximum depths were practical in actual condition. The actual field application shows that this research has significance help in safety jetting construction design.%准确了解深水钻井导管喷射极限下入深度对安全、高效深水钻井具有重要的意义。根据导管喷射下入系统的受力分析，对影响导管极限下入的土质参数及施工参数进行了研究，土质参数的影响因素主要包括土体抗剪强度和土体摩阻力；施工参数的影响因素主要包括喷射钻压、喷射排量及导管垂直度。基于对喷射过程中导管下入系统合力为0的工况进行研究，建立了深水钻井导管极限下入深度的预测模型；运用预测模型对南海某深水井的导管喷射进行了实例计算，得出了实际工况下导管喷射最小下入深度及最大下入深度。现场应用结果表明，该研究成果对安全喷射施工设计具有指导意义。