Longitudinal Guided Wave Inspection of Small-Diameter Elbowed Steel Tubes with a Novel Squirrel-Cage Magnetostrictive Sensor
Longitudinal Guided Wave Inspection of Small-Diameter Elbowed Steel Tubes with a Novel Squirrel-Cage Magnetostrictive Sensor
复制标题
采用新型鼠笼磁致伸缩传感器对小直径弯头钢管进行纵向导波检测
DOI：
10.1155/2019/3027372
复制
发表时间：
2019-11-12
影响因子：
1.9
通讯作者：
He, Cunfu
中科院分区：
文献类型：
--
作者：
Liu, Yao;Liu, Xiucheng;He, Cunfu
采用超声纵模导波对直径为10 mm的弯管(无焊缝)进行缺陷检测。有限元模拟结果表明，发射的L(0，1)模导波在弯曲区经历了强反射和模式转换，产生了F(1，1)模，然后是慢和弱的F(2，1)模。肘部有穿透性缺陷时反射的导波表现为两个重叠的波包，是肘部缺陷的良好指标。为了对小直径弯管进行L(0，1)模导波检测，实验中使用了一种新型的定制鼠笼式磁致伸缩传感器。该传感器采用分段铁钴条和小尺寸永磁体阵列的结构。整个传感器由两个相同的C型传感器元件组成，可以方便地回收和安装。对健康管子和缺陷管子的实验结果与有限元模拟得到的结论一致。通过对比实验信号和模拟结果，L(0，1)模导波可以同时检测弯头处的人工穿透缺陷和管子直部的缺口缺陷。
In the study, ultrasonic longitudinal mode guided waves were employed to detect defects in elbowed tubes (without welds) with a diameter of 10 mm. Finite element simulation results highlighted that the emitted L(0,1) mode guided waves experienced strong reflection and mode conversion at the elbow region to generate F(1,1) mode, followed by slow and weak F(2,1) mode. The guided wave reflected from the elbow with a through-wall defect was manifested as two overlapped wave packets, which were good indicators of a defective elbow. To conduct L(0,1) mode guided waves inspection on the small-diameter elbowed tubes, a novel tailored squirrel-cage magnetostrictive sensor was employed in the experiment. The new sensor employed the configuration of segmental iron-cobalt strips and small-size permanent magnet arrays. The entire sensor is composed of two identical C-shaped sensor elements and can be recycled and installed conveniently. Experimental results obtained from healthy and defective tubes were consistent with the conclusions obtained from finite element simulations. An artificial through-wall defect at the elbow and a notch defect at the straight part of the tube could be simultaneously detected by L(0,1) mode guided waves through comparing experimental signals with simulation results.