【摘要】 为实现采油管柱中的在役油管内壁腐蚀缺陷高精度离线检测，本文提出了一种基于双磁场传感的脉冲涡流外检测及深度定量评估方法。在试验研究中，以检测信号下降沿对数曲线斜率作为信号特征。在建立信号特征与油管剩余壁厚间映射关系的基础上，通过分析感应涡流在油管内分布范围与成像检测所识别腐蚀缺陷区域间的互相关关系，引入腐蚀缺陷深度评估补偿系数β。结合所建立映射关系，形成油管内壁腐蚀缺陷深度高效可视化定量评估方法。通过对缺陷成像及深度定量评估结果与真实情况的对比分析发现：所提方法不仅可实现对油管内壁腐蚀缺陷的三维形貌重现，且对其深度的定量评估具有较高的精度，满足工程实际在役油管的检测精度要求。更多还原

【Abstract】 In order to realize high-precision offline detection of corrosion desects on inner wall of in-service production tubing in oil well strings, a method based on dual magnetic field sensing for external detection of pulsed eddy current and depth quantitative evaluation is proposed.In the experimental study, the slope of the logarithmic curve of the falling edge of the detection signal is used as the signal feature.Based on the mapping relationship between the signal feature and the remaining wall thickness of the tubing, by analyzing cross-correlation relationship between the distribution range of induced eddy current in the tubing and the corrosion defects area identified by imaging detection, and the corrosion defects depth evaluation compensation coefficient β is introduced.Combined with the established mapping relationship, an efficient visual quantitative evaluation method for the depth of corrosions defects on the inner wall of oil pipes is formed.Through comparative analysis of defects imaging and depth quantitative evaluation results with the real situation, it is found that the proposed method can not only achieve three-dimensional morphology remerge of corrosion defects on the inner wall of the tubing, but also has high precision in quantitative evaluation of the corrosion depth, meeting the precision requirements of the detection of in-service oil tube in engineering practice.更多还原