Analysis of Acoustic Emission Signals for Condition Monitoring of Check Valve at Nuclear Power Plants

Abstract

The purpose of this research is to identify and recommend methods of inspection, surveillance, and monitoring that would provide timely detection of valve degradation and service wear so that maintenance or replacement could be performed prior to loss of safety functions. This research is focused on the capability of acoustic emission (AE) technique to provide diagnostic information on the determination of check valve aging and degradation, check valve failures and undesirable operating modes. Several commercially available check valve diagnostic-monitoring methods were evaluated, especially for the techniques based on measurements of acoustic emission, ultrasonic, and accelerometers. In the present paper, acoustic emission signals due to leak from check valve with artificially leakage and artificially worn disk were studied both analytically and experimentally. The results of development of advanced signal processing and de-noising techniques also have been presented.

Electroencephalogram-Based Human Performance Analysis for Improved Small Modular Reactor Operation

“…Rule-based models are used primarily when a checklist or manual is required to complete the task (e.g., following the steps documented in a manual to fix a specific problem in the reactor). Lastly, the knowledge-based model is a complex model used when operators are met with a new problem in which skill or rule-based models are unavailable (Lee et al, 2004;Kim et al, 2020).…”

Nondestructive Detection of Valves Using Acoustic Emission Technique

“…Lee and Kim et al systematically studied the relations between AErms and failure modes such as disk wear and foreign object of check valves. In their study, an advanced condition monitoring technique based on AE detection and artificial neural networks was applied to the valve, which could successfully finish the evaluation of different types of failure modes [26,59,60]. The schematic diagram for condition monitoring test of the valve is shown in Figure 4.…”

A study of the characteristics of the acoustic emission signals for condition monitoring of check valves in nuclear power plants

“…Several commercially available check valve diagnostic-monitoring methods were evaluated, especially the techniques based on the measurement of acoustic emission, ultrasonic, and the accelerometer. The methodology employed in this work is basically a three monitoring approach (Lee et al, 2004;Lee and Lee, 2002). The acoustic emission signals due to leaks from a check valve with artificial leakage and artificially worn disks were studied experimentally.…”