奥氏体不锈钢换热器管的涡流检测

Eddy Current Testing of Austenitic Stainless Steel Heat Exchanger Tube

介绍采用双频涡流技术检测奥氏体不锈钢换热器管。在对比样管上的检测试验发现,样管上的相位-壁厚减薄曲线与各类文献中的缺陷标准曲线存在较大差异。比较了自然缺陷与人工缺陷信号间的差异,分析了因换热器管在制造过程中形成的台阶状壁厚变化导致的伪缺陷信号。利用幅-相报警功能可辅助监控被检区域。结果表明,涡流检测速度快、成本低,可有效应用于奥氏体不锈钢换热器管的检测。

Double frequency method of conventional eddy current testing technology to inspect the austenitic stainless steel heat exchanger tube was introduced. It showed that the curve of phase against thickness decrease was greatly different from the stand curve in several kinds of literatures. The difference between the nature defect and artificial defect signals was compared, and the false defect signal excited by step-change of thickness in heat exchanger tube formed in manufacturing process was analyzed. Defect ...