基于柔性钻具低成本超短半径老井侧钻技术

The Low Cost Ultra-short Radius Sidetracking Technology in Produced Wells Based on Flexible Drill Pipe

为增加单井泄油面积,快速提高单井产量,为后续压裂作业提供优势流道,基于柔性钻具开发了低成本超短半径老井侧钻技术,设计了十字万向节结构柔性钻具,确定了适用于5(1/2)in套管井的柔性钻具结构单元主要参数:外径102 mm,单节长度150 mm,单节弯转角度5°。利用ANSYS有限元软件仿真分析柔性钻具水平钻进情况下的抗扭性能,仿真结果表明:柔性钻具力学性能达到强度要求。超短半径老井侧钻技术现场试验时,完钻最大井斜角87.3°,水平段井斜角波动不足1°,侧钻曲率半径1.8 m,水平钻进距离80.1 m,满足设计要求。侧钻完井后该井产液量由1.2 m^3/d升高至5.3 m^3/d,产油量由0.7 t/d升高至3.1 t/d,井网注采关系得以改善。超短半径侧钻技术的成功研发对油田开发后期挖潜剩余油具有重要意义。

In order to increase the drainage area and rapidly increase the production of single well, and to provide flow channel for the subsequent fracturing operation, the low cost ultra-short radius sidetracking drilling technology has been developed based on the flexible drill pipe. The flexible drill pipe with universal joint cross has been designed. The main parameters of flexible drill pipe unit for the 5）4 in casing well have been determined： 102 mm OD, 150 mm single section length and 5° of the maximum turning angle of the single section. ANSYS was used to analyze the torsional performance of flexible drill pipe during horizontal well drilling. The results showed that the mechanical properties of flexible drill pipe met the strength requirements. In the field test, the maximum inclination was 87. 3°, the inclination deviation of horizontal section was less than 1°, the radius of sidetracking was 1. 8 m, and the horizontal drilling distance was 80. 1 m, which met the design requirements. After the completion of the sidetracking, the test well fluid production increased from 1. 2 to 5. 3 m3/d, and the oil production increased from 0. 7 to 3. 1 t /d. The injection and production performance of the well pattern was improved.