救援井电磁探测定位方法及工具研究

Research on Electromagnetic Detection and Positioning Methods and Tools for Relief Wells

为了提高靶点精度,连通救援井与事故井,需要利用探测定位工具确定事故井的井眼位置,而国内目前缺乏相关的成熟技术。针对这一问题,提出了一种基于对称激励的瞬变电磁救援井探测定位方法,根据麦克斯韦方程建立了探测距离和方位的计算模型,研制了救援井探测定位工具样机,进行了救援井电磁探测定位工具井下试验。试验结果显示,电磁探测定位工具的最大探测距离可达24.0 m,距离误差小于10%,方位误差小于5°。研究结果表明,该电磁探测工具可对事故井的井眼进行准确定位,可为救援井与事故井的直接连通提供保障,并为形成具有我国自主知识产权的救援井探测定位和连通技术奠定了基础。

In order to connect relief wells with blowout wells and improve the accuracy of the target points,it is necessary to determine the borehole position of the blowout well with detection and positioning tools.However,there is currently a lack of relevant mature technology in China.In order to solve this problem,a transient electromagnetic relief well detection and positioning method is proposed in this paper based on symmetrical excitation.A calculation model for the detection distance and azimuth was derived from Maxwell’s equations,upon which a prototype of a relief-well detection and positioning tool was developed,and then tested in downhole condition.The test result showed that the maximum detection distance of this tool reached 24.0 m,with the errors of distance and azimuth less than 10%and 5°,respectively.The research indicated that the tool could accurately locate the borehole of the blowout wells and directly connect the relief wells with the blowout wells,which laid a foundation for the relief well detection,positioning and connection technology with independent intellectual property rights in China.