摘要
电磁超声检测方法常作为管道缺陷在线监测的无损检测手段。但由于电路振荡等原因,电磁超声检测方法存在一定的近场检测盲区。电磁-声复合检测方法在实现电磁超声监测的基础上,利用其检测过程中产生的脉冲涡流对管道表面及近表面的缺陷进行检测。但目前的研究表明,电磁-声复合检测方法普遍采用同时同频的激励策略,使得脉冲涡流的检测范围有限,导致复合方法仍存在检测盲带。为了减小复合方法的检测盲带,提出分时不同频激励策略。首先,建立一套分时检测系统,对射频开关和激励频率进行控制,实现高频激励电磁超声、低频激励脉冲涡流的目的。其次,基于不同频率的激励信号,计算对比了不同激励频率下电磁超声和脉冲涡流的检测性能。最后,通过试验结果验证了,采用分时策略可以提高电磁-声复合检测方法中电磁超声检测信号的信噪比以及脉冲涡流检测方法的检测范围。
Electromagnetic acoustic transducer(EMAT)can be used as a kind of nondestructive testing method for on-line monitoring of pipeline defects.Due to circuit oscillations and other reasons,EMAT exists blind area.The pulsed eddy current testing and electromagnetic acoustic transducer(PECT-EMAT)hybrid testing methods enable electromagnetic ultrasonic monitoring,which use the pulsed eddy currents generated during the detection process to inspect defects on and near the surface of the pipeline.Recently,most research shows that the excitation strategy of the hybrid testing method is single frequency,which makes the detection range of pulsed eddy current testing limited.In order to reduce the blind area of the composite methods,a time-sharing excitation strategy with different frequencies is put forward.Firstly,a time-sharing detection system was established.Through controlling the RF switch and the excitation frequency,EMAT is excited by a signal of high frequency and PECT is excited by a signal of low frequency.Then,the detection capabilities of EMAT and PECT at different excitation frequencies are compared by simulations and experiments.The results both show that the time-sharing strategy can not only improve the signal-noise ratio of EMAT,but also improve the detection range of PECT.
作者
胡朋
赵瑞祥
杨淑言
段志荣
解社娟
陈振茂
郑阳
HU Peng;ZHAO Ruixiang;YANG Shuyan;DUAN Zhirong;XIE Shejuan;CHEN Zhenmao;ZHENG Yang(State Key Laboratory for Strength and Vibration of Mechanical Structures,Xi’an Jiaotong University,Xi’an 710049;Shaanxi Engineering Research Center of Nondestructive Testing and Structural Integrity Evaluation,Xi’an Jiaotong University,Xi’an 710049;School of Aerospace Engineering,Xi’an Jiaotong University,Xi’an 710049;Shaanxi Special Equipment Inspection and Testing Institute,Xi’an 710048;China Special Equipment Inspection and Research Institute,Beijing 100029)
出处
《机械工程学报》
北大核心
2025年第2期1-10,共10页
Journal of Mechanical Engineering
基金
国家重点研发计划(2022YFC3005001,2023YFF0615200)
国家自然科学基金(U2130206,12222207)资助项目。
关键词
管道无损检测
电磁-声复合检测
分时策略
脉冲涡流
电磁超声
pipeline NDT
PECT-EMAT hybrid testing method
time-sharing strategy
pulsed eddy current testing
electromagnetic acoustic transducer
