Abstract: This paper analyzes the present conditions of electromagnetic propagation resistivity LWD tool both at home and abroad and comes up with the necessity and urgency of research and development of electromagnetic propagation resistivity LWD tool. The general design plan is based on the measurement principle and designing indexes of electromagnetic propagation resistivity LWD tool. The research and design are focused on electromagnetic propagation resistivity method, design of antenna, mechanical structure and electronic circuit. The 3D limited element method is used to bring electromagnetic LWD under numerical simulation study, optimizing the design of tool structure and probing characters. The design is also optimized for drilling collar mechanical layout, antenna structure and threading hole structure while the detailed design of circuit is focused on how to acquire attenuation amplitude of high-frequency weak acceptance signals and phase differential information. The tool is tested on the field after its successful research and development. The results indicate that the tool is good at compatibility and repeatability of logging curves and satisfies the demand for geological pilot and formation interpretation and evaluation.

摘要： 文章分析了电磁波电阻率随钻测井仪国内外研究应用现状, 提出研发电磁波电阻率随钻测井仪的必要性 和紧迫性。根据电磁波电阻率随钻测井仪的测量原理和设计指标, 确定总体设计方案, 从电磁波电阻率方法、天线设 计、机械结构、电子电路等方面开展研究和设计。利用三维有限元方法对随钻电磁波测井进行数值模拟研究, 对仪器 结构、探测特性, 以及钻铤机械结构布局、天线结构、穿线孔结构等进行优化设计; 针对如何提取高频微弱接收信号 的衰减幅度和相位差信息, 进行电路详细设计。仪器现场试验显示, 测井曲线一致性和重复性较好, 能够满足地质导 向和地层解释评价的需要。

关键词: 电磁波, 电阻率, 随钻测井仪, 对称补偿, 数值模拟, 机械设计, 有限元方法, 电路设计及应用