深水钻井喷射下导管水力参数优化设计方法

Optimal Design of Hydraulic Parameters for Conductor Jetting in Deepwater Drilling

王磊 张辉 周宇阳 柯珂 张进双 彭兴

Wang Lei Zhang Hui Zhou Yuyang Ke Ke Zhang Jinshuang Peng Xing

中国石化石油工程技术研究院, 北京 100101; 中国石油大学(北京)石油工程学院, 北京 102249

Sinopec Research Institute of Petroleum Engineering, Beijing, 100101, China; College of Petroleum Engineering, China University of Petroleum (Beijing), Beijing, 102249, China

针对目前现有深水钻井喷射下导管水力参数设计方法没有较强理论支撑的问题,以射流和岩土力学理论为基础,推导出了导管喷射下入临界出口速度及临界排量的计算公式,并据此提出了深水钻井喷射下导管水力参数的优化设计方法,给出了设计原则和设计步骤.分析了深水钻井喷射下导管常用钻头与导管组合采用不同直径喷嘴时的临界排量,对于φ660.4 mm钻头和φ762.0 mm导管的组合,喷嘴当量直径为24.0 mm时,临界排量为69.5 L/s;喷嘴当量直径为26.0~30.0 mm时,破土直径最大为762.0 mm.在排量一定的情况下,喷嘴当量直径越小,能够破碎地层的强度也越高.对西非深水JDZ区块深水钻井喷射下导管的水力参数进行设计,选用φ14.3 mm喷嘴时,设计排量与实钻排量对比,误差不超过10%,证明该优化设计方法的设计结果合理,可用于深水钻井喷射下导管水力参数设计,指导现场施工.

Considering that there is no strong theory support to the design of hydraulic parameters in conductor jetting in deep water drilling, the calculation formulas of critical jet outlet velocity and flow rate in jetting were derived based on the water jetting theory and rock mechanics, by which an optimal design methods, criteria and procedures were presented, and investigated. The combination patterns of different bits and conductors used in jetting, showing that the critical jet flow rate was 69.5 L/s for the combination of φ660.4 mm bit and φ762.0 mm conductor, with 24.0 mm equivalent nozzle diameter, and the maximum breaking diameter was 762.0 mm when the nozzle diameter was 26.0-30.0 mm. Given constant jet flow rate, the smaller the equivalent nozzle diameter, the greater the breaking strength is. Taking the design of hydraulic parameters in deep water jetting drilling in JDZ Block, West Africa, as example, the error between designed and actual jet flow rates was less than 10% if φ14.3 mm nozzle was used. It proved that this optimal design method was reasonable and it could be effectively used in design of hydraulic parameters in deepwater conductor jetting operations.

中国石化科技攻关项目“琼东南深水钻井关键技术研究”(编号:P13010)部分研究内容.

https://doi.org/10.11911/syztjs.201502004