Review of statistical methods for assessing the probability of detecting defects in non-destructive testing

The probability of detection (POD) depends on defects size and is an integral part of calculating the resource during non-destructive testing of parts. This article provides an overview of well-established statistical methods for estimating PODs, with a little historical insight into their emergence. An overview of new advances in POD calculation in recent years is given: three- and four-parameter models; nonparametric models; planning the experiment and sampling of defects; applying defect modeling to reduce the number of samples; the application of the Box-Cox transformation; the influence of the variability of the initial data on the result; application of Bayesian statistics. An overview of the tasks that POD specialists still have to solve in the future: nonlinear models, modeling in conjunction with Bayesian statistics, etc

Eddy Current Experience of Pipe NPP Heat Exchange Equipment Testing

The article describes the results of the application of the eddy current method for nondestructive testing of heat-exchange tubes at operating NPPs. Typically tubes are produced of copper-nickel alloys and stainless steel. For the purpose of examining tubes of different materials eddy current probes of different types were used in order to increase reliability and precision. In order to obtain information on real flaw dimensions tubes were cut and examined using metallography equipment.