脉冲漏磁检测管道技术的有限元分析

漏磁检测方法作为一种无损检测技术广泛应用于钢材等的检测。分析了脉冲漏磁检测原理，提出了脉冲交流磁化方式。采用有限元法对系统参数变化等影响缺陷漏磁场分布因素进行了仿真计算，分析了提离、缺陷深度及宽度等变化对脉冲漏磁检测结果的影响。结果表明在较大提离情况下，脉冲漏磁检测方法具有可提取较多检测信息、输出电压幅值高的优点，在钢管的缺陷检测中将有广阔的应用前景。

Finite Element Numerical Simulation on Steel Pipe Using Pulsed Magnetic Flux Leakage Testing

Magnetic flux leakage techinique had been widely used for non-intrusively testing of steel products. The principle of pulsed magnetic flux leakage testing（PMFL） was analyzed. A pulsed alternating current magneting method was presented. The finite element numerical simulation had been used to simulate and calculate the effects on various of parameter of the detection system. The influences of changes of lift-off, defect depth and length of the pulsed magnetic field leakage were studied by way of finite element numerical simulation. The results showed that PMFL had the advantage of high signal amplitude and more useful testing information, and this making the method had the broad using foreground in the testing of steel pipe.