公开(公告)号：US20090102473A1

公开(公告)日：2009-04-23

申请号：US12255196

申请日：2008-10-21

申请人： Soshi NARISHIGE ,  Akira Nishimizu ,  Masahiro Koike ,  Yoshiharu Abe ,  Yuichi Narumi

发明人： Soshi NARISHIGE ,  Akira Nishimizu ,  Masahiro Koike ,  Yoshiharu Abe ,  Yuichi Narumi

IPC分类号： G01N27/90

CPC分类号： G01N27/90

摘要： The present invention provides an eddy current testing method and an eddy current testing apparatus that can reduce detection noise to increase the SN ratio thus improving the defect detection accuracy.An eddy current testing sensor includes a pair of excitation coils and a detection coil disposed therebetween. For example, a voltage regulator applies voltages having different amplitudes to the pair of excitation coils so as to reduce detection noise caused by a deformed portion of a heat exchanger tube and a tube plate in a detection signal of the detection coil. Alternatively, for example, an eddy current testing detector applies a first excitation frequency f1, at which tube material noise is reduced to negligible an amplitude, and a second excitation frequency f2, which is higher than the first excitation frequency f1, to the eddy current testing sensor. The phase and gain of a measurement waveform with the second excitation frequency f2 are adjusted and then a differential waveform of the first and second excitation frequencies f1 and f2 is obtained based on an induction voltage detected by the detection coil so as to cancel out tube expansion noise.

摘要翻译： 本发明提供涡流检测方法和涡流检测装置，其可以降低检测噪声以增加SN比，从而提高缺陷检测精度。 涡流检测传感器包括一对励磁线圈和设置在其间的检测线圈。 例如，电压调节器对一对励磁线圈施加具有不同振幅的电压，以便降低由检测线圈的检测信号中的热交换器管和管板的变形部分引起的检测噪声。 或者，例如，涡电流测试检测器将管材噪声降低到可忽略的振幅的第一激励频率f1和高于第一激励频率f1的第二激励频率f2施加到涡流 测试传感器。 调整具有第二激励频率f2的测量波形的相位和增益，然后基于由检测线圈检测到的感应电压获得第一和第二激励频率f1和f2的差分波形，以抵消管膨胀 噪声。