基于远场涡流检测技术的铁磁性热交换器管仿真研究

Researches on mechanism simulation of ferromagnetic heat exchanger pipes based on remote field eddy current detection technology

石油、化工、电力等行业频繁出现热交换器管的泄漏事故,给企业带来经济损失,同时会对现场工作人员的生命安全造成威胁。为能够快速有效地对服役管道进行无损检测,本文基于远场涡流检测机理,对铁磁性热交换器管进行仿真分析与实验研究。结果表明,远场区的位置随着壁厚和管内径的增加而变远,并且对于相同大小的缺陷,远场区的检测灵敏度高,但当相同大小的缺陷位于内外壁时磁感应强度差值的变化近似相等,这与真实管道缺陷检测的实验结果一致,满足远场涡流检测原理。结论认为,远场涡流检测技术能够较好地判定和识别铁磁性管道缺陷,对服役管道在线无损检测以及安全性能评估具有良好的应用前景。

Frequent leakage of heat exchanger pipes in petroleum,chemical,electric power and other industries will not only bring economic loss to enterprises,but threaten the workers working in site.In order to carry out non-destructive testing of the service pipes quickly and effectively,simulations and analyses are performed experimentally on the ferromagnetic heat exchanger pipes according to the detection mechanism of far field eddy current.The results show that the position of the remote field will be enlarged with increasing the wall thickness and the inner diameter of the pipes,and the detection sensitivity of the remote field is high for the condition with the same size defect,but the difference of the magnetic flux intensity varies equally when the defects with the same size are located at the inner and outer walls.This is consistent with the practical experiment results of real pipe defect detection and meets the principle of remote field eddy current detection.It can be concluded that the remote field eddy current testing technology can determine and identify ferromagnetic pipe defects better,and has a good application prospect for online nondestructive testing and safety performance evaluation of service pipelines.