海上加密调整井隔水导管定向打桩模型构建与应用

Research and application of conductor directional piling model for the offshore infill adjusting wells

隔水导管定向打桩可有效解决海上加密调整井浅层防碰问题,但目前隔水导管定向打桩缺乏理论模型,作业存在安全风险。根据钻井设计及现场作业需求,首先通过导管鞋受力分析和历史作业数据反演,构建和优化了隔水导管定向打桩井斜角、偏移距离理论模型,然后通过导管与地层的承载力分析,构建了隔水导管定向打桩入泥深度设计模型。研究表明:导管鞋坡口角度是影响定向打桩效果的关键因素,坡口角度合理范围为20°~45°,具体角度需要根据井场地质条件和导管参数进行计算。构建的理论模型在南海东部海上隔水导管定向打桩作业中进行了应用,成功规避了加密调整井浅层碰撞风险,保证了海上作业安全。本研究成果可为海上加密调整井隔水导管定向打桩作业提供理论支撑。

The directional piling driving of conductor is an effective method to solve the problem of shallow anti-collision problem in offshore infill adjusting wells.However,the lack of corresponding theoretical model leads to safety risks in pile driving operations.Based on the analysis of the force on the casing shoe and the inversion of historical operation data,theoretical models of directional piling angle and deviation distance were constructed and optimized through the mechanical analysis between conductor and formation in response to drilling design and on-site operation requirements.and inversion of historical operation data.Then,the design model of the directional piling setting depth was constructed through the analysis of the bearing capacity between the conductor and formation.This research indicates that the slope angle of conductor shoe is the key factor affecting the effectiveness of directional piling.The slope angle of 20°-45°is a reasonable selection range,and the specific angle should be calculated according to the geological conditions of the well site and the parameters of the conductor.The theoretical model has been applied in the eastern of South China Sea.The application results indicate that the shallow collision risk of infll adjustment wells has been avoided,ensuring the safety of offshore operations.The research results of this paper can provide theoretical support for offshore directional pile driving operations of the offshore infill adjusting well.