陀螺减振工具与PDC钻头在花岗岩潜山地层的应用

摘要

The PDC bit is prone to stick-slip vibration in drilling hard formation, leading to low ROP and short footage.Applying the gyro shock-damping tool and optimizing PDC bit are proposed to reduce the stick-slip vibration in drilling granite buried hill and to extend the drill bit life.The gyro shock-damping tool combined with the specific PDC bit has been tested in the 630~869 m granite bedrock section in Chad, achieving the performance of 239 m footage, drilling time of 54 h and the ROP of 4.44 m/h.Compared with the footage of less than 11 m and the ROP of less than 1.23 m/h of the offset wells 3 PDC bits, the bit index has been greatly improved.Compared with the 43 tricone bits, the average ROP and the average footage has been improved by 97.33% and 54.19% respectively.The technology could be promoted in granite buried hill horizontal wells, hard formation and soft-hard interlayer.%PDC钻头在硬地层中钻进时易发生黏滑振动,导致钻速低、进尺短.采用陀螺减振工具和优化设计PDC钻头的方法减少在花岗岩潜山地层中钻进时的黏滑振动,以延长钻头寿命.陀螺减振工具配合个性化PDC钻头在乍得花岗岩基岩井段630~869 m进行试验,取得进尺239 m、纯钻时间54 h、机械钻速4.44 m/h的良好效果,与邻井3只PDC钻头进尺小于11 m、钻速低于1.23 m/h相比,钻头指标大幅度提高,与邻井43只牙轮钻头相比,平均机械钻速提高 97.33%,平均进尺提高54.19%.该技术可在花岗岩潜山水平井、硬地层及软硬交错地层推广应用.