储罐直径对罐壁腐蚀缺陷的漏磁场信号影响分析

Analysis of Influence of Tank Diameter on Leakage Magnetic Field Signal of Corrosion Defects in Tank Wall

受腐蚀因素影响,储罐易发生腐蚀泄漏,储罐罐壁腐蚀一直是无损检测的难点,开展罐壁腐蚀缺陷漏磁检测技术研究。在轴向磁化方式下,对储罐壁板缺陷进行漏磁检测时,受壁板直径影响,同一缺陷处不同检测通道的漏磁信号不同,分析各通道漏磁信号与储罐直径的关系,得出直径与各通道漏磁信号峰值的数学模型;在此基础上对各通道漏磁信号进行预处理,建立修正系数,以消除不同通道之间的漏磁信号差异,实现各通道信号均匀化。

Influenced by corrosion,the tank tends to cause leakage. It is a difficult point to detect tank wall corrosion using non-destructive testing. In order to solve this situation,this topic proposed a method to research corrosion defects for tank wall by magnetic flux leakage( MFL). In axial magnetization mode,the MFL signals detected with different detect channels for the same defect are different,which caused by wall plate diameter. A mathematical model of the relationship between diameter and MFL signal peak is constructed,based on analysis of the signal and tank diameter. Furthermore,MFL signals of each channel are pre-processed and the correction coefficient is established. According to computing model,the signals detected by different channels of the same defect can achieve homogeneously.