The micro-crack for sucker rod is inspected by magnetic flux leakage inspection by now, but it is not good for accuracy and sensitivity.

• 针对目前漏磁检测抽油杆微裂纹的精度和灵敏度不高的现状,提出一种通过拉伸抽油杆使微裂纹张开后的漏磁检测法。