金属管道腐蚀量的电磁法检测

Electromagnetic detection of metal pipeline corrosion volume

为了进一步研究埋地金属管道腐蚀量的算法,分析了瞬变电磁法检测信号的衰变规律,搭建了试验平台,将获得的感应电压信号从笛卡尔坐标系变换为双对数坐标系,选择衰减斜率为壁厚的特征值,通过函数关系式y=2.5895x^(-0.439)进行拟合,得出壁厚与衰减率的数学模型,最后选取其他钢板试件验证该数学模型的正确性。结果表明:该检测方法能够有效地应用于金属管道的壁厚检测中,具有检测范围广,壁厚计算误差不超过5%,且不受提离高度影响等优点;为无损检测技术的传感器设计、优化及功能拓展提供了理论依据。

In order to further study the quantitative algorithm of buried metal pipeline corrosion,the decay law of TEM detection signal is analyzed firstly,and then a test bench is built to change the obtained induced voltage signal from Cartesian coordinate system to double logarithm coordinate system,and the attenuation slope is extracted as the characteristic value through the function y=2.5895x^(-0.439) to get the mathematical model of wall thickness and decay rate.Finally,other steel samples were selected to verify the correctness of the mathematical model.The results show that the detection method can be effectively applied to the metal pipe wall thickness detection with a wide range of detection,and the wall thickness calculation error is not more than 5%,and is not affected by the lifting height.It provides a theoretical basis for the sensor design,optimization and function expansion of nondestructive testing technology.