冲顶开窗径向水平井转向送进关键技术

为解决传统径向水平井技术套管段铣和大直径扩孔困难等问题,提出在免扩孔条件下一次性实现径向水平井开窗及钻进的技术方案,设计在Φ139.7 mm套管内使用的转向工具,该工具利用液压冲顶方式进行套管开窗,并采用Φ14 mm无缝钢管作为喷射钻进的钻管。数值模拟与室内试验表明,采用纵向冲顶方式可满足套管开窗要求;在45 MPa泵压作用下钻管能够克服转向阻力实现送进;当冲头下倾角度为11°时能有效地实现钻管矫直与长距离送进;采用液压冲顶套管与金属钻管送进相结合的方式可满足超短半径径向水平井作业要求,为下一步联合水力钻头进行高压喷射破岩奠定基础。

Key technology of steering feed in perforating casing to drill radial horizontal well

It is difficult to mill casing and ream large diameter holes with conventional radial horizontal well drilling technology. To solve the problem, a new technology design was proposed in this work, using which casing can be milled and radial horizontal wells can be drilled without reaming. A steering tool was designed to be used in 139.7 mm casings. This steering tool uses hydraulic puncher to mill casing, and then a steel pipe with 14 mm diameter is used as drilling pipe. The results of numerical simulation and laboratory tests show that vertical hydraulic punching can meet the requirements of milling casing and the drill pipe is able to overcome the resistance and drill forward with 45 MPa hydraulic pressure. The results also indicate that when the tilting angle of the punch is 11°, it can align the drill pipe completely and effectively drill the horizontal hole to a long extension. It is proved that using hydraulic puncher combined with metal drilling pipe can achieve ultra short radius radial penetration operation and lay foundations for the next step, during which a hydraulic drilling bit is used to efficiently break the rock with high pressure water jet.