水力喷射侧钻径向水平井眼延伸能力

Extension ability of hydra-jet sidetracking of radial horizontal well

 毕刚¹ 马东军² 李根生³ 黄中伟³ 窦亮彬¹

西安石油大学石油工程学院，陕西 西安 710065 中国石化石油工程技术研究院，北京 100101 中国石油大学（北京）油气资源与探测国家重点实验室，北京 102249）

School of Petroleum Engineering, Xi′an Shiyou University, Xi′an 710065, China Research Institute of Petroleum Engineering, SINOPEC, Beijing 100101, China State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, China)

 径向水平井钻井技术的一个主要指标是水平井眼的延伸长度。根据水力喷射侧钻径向水平井技术的特点，基于流体力学、计算流体力学及射流动力学等理论，对射流钻头自进力进行了理论分析，建立了径向水平井眼极限延伸长度的计算模型，分析了摩擦因数、后向孔眼个数、后向孔眼直径、后向孔眼扩散角和流量等参数对径向水平井眼极限延伸长度的影响。结果表明：改变系统的后向孔眼个数、后向孔眼直径和流量，可以使径向水平井的极限延伸长度发生明显改变；改变后向孔眼扩散角，只能在一定范围内改变径向水平井的极限延伸长度。所建立的模型和得出的规律可以为径向水平井的施工设计及射流钻头结构优化等提供理论指导。

 The extension length of horizontal wellbore is an important indicator for radial horizontal well drilling technology. Based on the behavior of radial horizontal well drilling by hydraulic jetting, the theories of fluid dynamics, computational fluid dynamics, and jet dynamics, etc., the self-propelled force of jet bit was analyzed. And the calculation model of the limit extension length for radial horizontal well was established. Moreover, the impacts of friction factor, flow rate, the number and the diameter of backward nozzle and the orifice diffusion angle on the extension ability of radial horizontal well were analyzed theoretically. The results show that the extension ability changes obviously with the variation of flow rate, the number and the diameter of backward nozzle. However, the orifice diffusion angle only has an effect on extension length within certain limits. The model and the results can provide theoretical guidance for construction design of radial horizontal drilling and structure optimization of jet bit.

10.6056/dkyqt201605022