非接触式磁检测技术在长输管道外检中的应用

Application of Non-Contact Magnetic Detection in External Test of Long Distance Pipeline

长输管道在失效断裂前往往会在相应的位置出现应力集中的现象,而传统的无损检测方法和漏磁检测技术无法对应力集中做出相应预警。非接触式磁检测技术利用铁磁材料具有金属磁记忆的特性,对管道上方的空间磁场梯度进行采取和分析,可以找到材料的应力集中区,从而发现材料的早期隐形损伤。非接触式磁检测技术成功地检测出了广西天然气管道的应力集中区,并利用金属磁记忆检测仪对较大隐患点进行开挖验证,验证结果和非接触式磁检测技术结论一致,证明了非接触式磁检测技术是检测铁磁材料应力集中的有效手段。

The phenomenon of stress concentration will occur at the corresponding position before the failure fracture of the long-distance pipeline. However, traditional non-destructive testing and magnetic flux leakage testing technology cannot make corresponding early-warning for stress concentration. The non-contact magnetic detection technology uses the characteristics of magnetic memory of ferromagnetic materials to collect and analyze the gradient of the space magnetic field above the pipe. It can find the stress concentration area of the material and the early damage of the material. The stress concentration area of Guangxi natural gas pipeline is successfully detected by non-contact magnetic detection technology. The metal magnetic memory detector is used to verify the excavation of points with greater hidden danger. The conclusion is consistent with the non-contact magnetic detection technology, which proves the feasibility of non-contact magnetic detection technology.