基于磁导率扰动的厚壁管道腐蚀检测

Corrosion Detection of Thick-Walled Pipes Based on Magnetic Permeability Perturbation

在复杂的工作条件下,流动腐蚀会导致厚壁管道局部壁厚发生变化。传统的电磁检测方法很难评估深层缺陷,由于磁导率扰动检测(MPPT)拥有对深埋缺陷钢管的高灵敏度优势,因此,采用磁导率扰动检测方法对厚壁管道腐蚀缺陷进行检测。对铁磁材料施加直流电磁化,由于壁薄引起的内部磁场扰动引起表层磁导率扰动,并通过涡流探头检测。实验结果表明:检测电压信号幅值随管壁减薄厚度的增加而增大,可以测量管壁减薄5%的情况。

Under complex working conditions,flow corrosion can lead to changes in local wall thickness of thick-walled pipes.The traditional electromagnetic detection method is difficult to evaluate the deep defects.Because of the high sensitivity of the deep-buried defective steel pipe,the permeability disturbance detection method is used to detect the corrosion defects of the thick wall pipe.Direct current magnetization is applied to the ferromagnetic material,and the surface permeability disturbance is caused by the internal magnetic field disturbance caused by the thin wall,which is detected by the eddy current probe.The experimental results show that the amplitude of the detected voltage signal increases with the increase of the thickness of the tube wall thinning,and the condition of 5%of the tube wall thinning can be measured.