新型双远场电磁聚焦测厚仪系统

摘要

In order to improve the accuracy of the thickness gauge to measure oil casing, according to the principle of emission electromagnetic field, the coil electromagnetic field distribution both inside and outside the oil casing is changed, and then the detection sensitivity of the instrument is improved under the condition of no push-backing system; The structure of far field low frequency double emission and array receiving probe is adopted, and then the horizontal resolution of instrument is improved. A envelope method of extracting amplitude of measured data is presented. A self-adaptive BP neural network algorithm of increasing the data change rate in the input samples is realized. The practice results show that, the instrument has the advantages of high measuring accuracy, high measuring speed and high resolution of the horizontal direction. Furthermore, the simple structure of instrument is convenient for production and promotion.%为了提高测厚仪测量石油套管的精度，根据发射电磁场原理，改变了线圈电磁场在石油套管内外的分布，使该测厚仪在不用推靠系统的条件下，提高了仪器的检测灵敏度；采用了远场低频双发射及阵列接收探头的结构，提高了仪器水平方向的分辨率。提出了能够快速准确地提取测得数据幅值的包络线法，实现了在输入样本中增加数据变化率的自适应BP神经网络算法。实验结果表明，该仪器具有测量精度高、速度快、水平方向的分辨率高的优点，而且结构简单便于生产推广。