随钻超声井眼成像可行性实验研究

随着油气勘探开发难度的不断增大，地质与工程条件日趋复杂， 施工风险日益加大， 井壁失稳、垮塌等问题制约钻完井工程效益及安全，随钻超声井眼成像技术可以在随钻工况下实时测量高精度的井径大小与井壁特征，获取高质量的井眼图像，为钻进过程中井眼工程状况和质量的监测提供了解决方案。为研发随钻超声井眼成像工具并对图像进行准确解释，进行了随钻超声井眼成像可行性实验研究。 设计搭建了实验装置与实验平台，制定了实验方案，进行了室内模拟实验，分析了不同测量距离、不同待测物、不同传输介质对超声波传输时间与回波幅值的影响。 实验结果表明： 超声波传输时间与测量距离呈线性正相关，可以用于井径的测量及井眼形状的识别；超声波回波幅值对井壁特征敏感，可以用于井壁缝隙、孔隙等特征的识别与成像；随钻超声井眼成像方法可以适用于高密度油基钻井液中。

Experimental Study on Feasibility of Ultrasonic Borehole Imaging While Drilling

With the increasing difficulty of oil and gas exploration and development, the geological and engineering conditions are becoming more and more complex, the construction risk is increasing, and the problems of wellbore instability and collapse restrict the efficiency and safety of drilling and completion engineering. The ultrasonic borehole imaging while drilling technology can measure the high-precision borehole diameter and wellbore characteristics, obtain high-quality borehole images while drilling in real time. It provides a solution for monitoring borehole engineering condition and quality while drilling. In order to develop ultrasonic borehole imaging while drilling tools and accurately interpret the images, this paper researches the feasibility of ultrasonic borehole imaging while drilling, builds and designs the experimental device and experimental platform and formulates the experimental scheme. Laboratory simulation experiments were carried out to analyze the effects of different measurement distance, different objects and different transmission medium on the travel time and echoamplitude of ultrasonic. The results show that the ultrasonic travel time has a positive linear correlation with the measurement distance, which can be used to measure the well diameter and identify borehole shape; ultrasonic echo amplitude is sensitive to borehole characteristics and can be used to identify and image the fracture aperture and bedding parting; ultra-sonic borehole imaging while drilling method can be used in high-density oil-based mud.