接收线圈位置对脉冲涡流检测灵敏度的影响

摘要

研究了对带包覆层管道的内部腐蚀进行脉冲涡流检测时，接收线圈的位置变化对检测灵敏度的影响，进行了探头置于激励线圈下不同位置的有限元仿真和试验研究。有限元仿真结果表明：在轴向和周向2个方向都是当检测线圈位于激励线圈边缘正下方时检测效果最好，其灵敏度分别为0.61、0.60。验证试验表明：在轴向和周向2个方向上，最佳检测位置都是位于激励线圈边缘正下方，其灵敏度分别为0.26、0.27。试验结果与仿真结果基本一致，表明接收线圈在激励线圈外边缘正下方附近时，检测灵敏度达到最大。研究结果有助于带包覆层管道腐蚀的脉冲涡流检测的传感器设计。%Effect of the detection sensitivity caused by the location change of the receiving coil is studied on the internal corrosion of ferromagnetic pipe under insulation with pulsed eddy current ( PEC ) non-destructive testing. Finite element model was established of ferromagnetic pipe under insulation to analyze the effect of position of receiving coil on the pulsed eddy current testing results. The simulation results show that the sensitivity will reach maximum both axial and circumferencial directions when receiving coil is right under the outer edge of the exciting coil, the sensitivities 0. 61 and 0. 60 respectively. The verification experiment results show that:putting receiving coil right under the outer edge of the exciting coil will get the best test results, the sensitivities 0. 26 and 0. 27 respectively. The experimental results agree well with the simulations and show that the detection sensitivity will reach maximum when receiving coil is right under the outer edge of the exciting coil, which will be of help to probe design in the corrosion detection of the pipe under insulation with PEC.