连续管钻井震击工具的设计及研究

Design of Jar Tool for Coiled Tubing Drilling

在连续管钻井过程中,由于连续管自身的特性,其加压后易出现摩擦自锁,进而导致轴向力传递效率低下、在水平段延伸困难等问题。为此设计了一种连续管震击工具,该工具通过提升泵入排量来启动工具,同时产生轴向震击和周向旋转,一定程度上解决了连续管钻井过程中的加压和托压问题,并且能提高机械钻速,延长钻头寿命。对工具关键部件冲击砧和圆柱销进行了有限元分析,结果表明其强度设计合理。针对工具的工作机理、震击频率和密封强度进行了地面试验,工具在工作频率达17-25 Hz,工作转速为3~11 r/min时,经长时间反复震击,没有出现泄漏,可正常工作,证明其设计合理、技术性能可靠。研究结果为国内连续管震击工具的研制提供了技术支持。

In the coiled tubing drilling,due to the characteristics of the coiled tubing,friction self-locking is prone to occur after put on weight,which leads to problems such as low axial force transmission efficiency and difficulty in horizontal section extension.To address the problem,a coiled tubing drilling jar is designed,which is actuated by increasing the pumping displacement,and simultaneously generates axial shock and circumferential rotation,addressing the back pressure issue in the coiled tubing drilling process to some extent and increasing the penetration rate and bit life.The finite element analysis of the cylindrical pin of the coiled tubing drilling jar shows that the strength design is reasonable.The ground test was carried out on the working mechanism,shock frequency and sealing of the tool.The result showed a working frequency of 17~25 Hz,the working speed of 3~11 r/min,and zero leak after a long time shock.The long time normal work indicated a reasonable design and a reliable technical performance.The study could provide technical support for the development of the domestic coiled tubing drilling jar.