基于脉冲涡流技术的提离高度和壁厚检测  

Lift-off height and wall thickness detection based on pulsed eddy current technology

作　　者：田亚团 TIAN Yatuan(Sinopec Engineering Quality Monitoring Co.,Ltd.,Beijing 100101,China)

机构地区：[1]中石化工程质量监测有限公司,北京100101

出　　处：《压力容器》2024年第7期71-78,共8页Pressure Vessel Technology

基　　金：中石化工程质量监测有限公司研发项目(DW-JCGS-2021-2)。

摘　　要：为了研究脉冲涡流技术在检测带有包覆层的压力容器或管道壁厚时,提离高度和保护层材质对检测结果的影响,分析了提离高度对脉冲涡流信号的影响,并提出了一种利用中期信号截距计算提离高度的方法,研究结果表明,不同保护层材质对脉冲涡流信号的影响各异,其中不锈钢皮影响较小;铝皮增加了信号幅值;而镀锌铁皮降低了信号幅值。在利用晚期信号斜率计算壁厚时,提离高度的影响较小,但对于铝皮保护层,计算壁厚随提离高度的增加而降低,需要用校准公式进行校准。通过试验验证,校准后的计算壁厚与实际壁厚相差不超过2%,表明校准方法是有效的。In order to investigate the impact of lift-off height and protective layer material on the detection results when using pulsed eddy current technology to measure the wall thickness of pressure vessels or pipelines with cladding,the effect of liftoff height on the pulsed eddy current signal was analyzed,and a method for calculating the lift-off height using the intercept of the mid-term signal was proposed.The research results show that different protective layer materials have different effects on the pulsed eddy current signal:stainless steel has a minimal impact,aluminum increases the signal amplitude,whereas galvanized iron reduces the signal amplitude.When calculating the wall thickness using the slope of the late-term signal,the impact of lift-off height is relatively small.However,for aluminum protective layers,the calculated wall thickness decreases with the increase of liftoff height,which needs to be calibrated using a formula.Experimental verification shows that the calibrated wall thickness differs from the actual wall thickness by no more than 2%,indicating that the calibration method is effective.

关 键 词：壁厚检测 脉冲涡流 中期信号截距 提离高度 

分 类 号：TH878.3[机械工程—仪器科学与技术] TG115.28[机械工程—精密仪器及机械] TB463.1[金属学及工艺—物理冶金]