Sensors and Actuators A: Physical ( IF 4.6 ) Pub Date : 2020-11-24 , DOI: 10.1016/j.sna.2020.112450 Jiuhao Ge , Baowang Hu , Chenkai Yang
The pulsed eddy current technique has received a great deal of attention in recent decades. To improve its performance and applicability, several kinds of probes, such as rectangular and gradient field probes for plate detection and encircling probes for tube detection, have been proposed. However, few bobbin-type pulsed eddy current probes have been proposed. This study proposes a bobbin pulsed eddy current array probe to simultaneously detect, classify and evaluate inner and outer surface defects in nonferromagnetic tubes. The probe contains double exciting coils and 20 sensors. The double exciting coils could generate stronger and more uniform induced eddy current in tube. The 20-sensors array could measure the complete circumferential magnetic signals above tube inner surface. Using the Br curves drawn by peak value and post peak value, inner and outer surface defects can be classified without beforehand training or the usage of complex process. Meanwhile, the maximum value in Br curve can be used to measure the defect depth and residual depth accurately.
中文翻译:
梭芯脉冲涡流阵列探头用于非铁磁管中缺陷的检测和分类
近几十年来,脉冲涡流技术已经引起了广泛的关注。为了提高其性能和适用性,已经提出了几种探针,例如用于板检测的矩形和梯度场探针以及用于管检测的环绕探针。但是,很少有人提出线轴型脉冲涡流探头。这项研究提出了一种线轴脉冲涡流阵列探头,可同时检测,分类和评估非铁磁管的内,外表面缺陷。该探头包含双励磁线圈和20个传感器。双励磁线圈可以在管内产生更强,更均匀的感应涡流。20个传感器的阵列可以测量管内表面上方的完整圆周磁信号。使用B r峰值和后期峰值绘制的曲线,内表面和外表面缺陷都可以分类,而无需事先训练或使用复杂的过程。同时,B r曲线中的最大值可用于精确测量缺陷深度和残余深度。