介绍了凝汽器不锈钢管常见缺陷与双频涡流检测阻抗信号间的关系。阐述了双频涡流检测技术的原理。通过试验分析，比较了各种缺陷信号间的差异，结合现场应用中缺陷信号的特征，得出阻抗信号参数与缺陷性质具有紧密关系的结论。试验分析结果不仅对同类型非铁磁性凝汽器管的涡流检测具有指导意义，也对进一步开展双频涡流检测的理论研究和实际应用具有很好的参考价值。

The relationships between defects of stainless steel tube of condenser and signal by doublefrequency eddy current test were introduced. By expounding the theory for doublefrequency eddy current test, and comparing the differences of these defect signals, combining with the application characteristics of defects signal, the closed relationships between common defect and impedance signal was put forward. The analysis results will guide significance of eddy current testing to the same type of condenser tube, also have a very good reference value for the further development of the theory of doublefrequency eddy current testing and practical application.