In this study, a study was conducted to improve the reliability of the valve by developing a valve leakage and reliability measurement system designed to secure the high quality and reliability of the butterfly valve. The system measuring the torque required for valve opening and closing operation, and was configured to operate after multiple opening and closing of the valve to check for leakage of the valve. Finally, a system that can perform efficient work in terms of productivity was developed by enabling leak inspection, torque measurement, and reliability inspection through one integrated system.

Flow visualization of Butterfly valve is tested five cases(15°, 30°, 45°, 60° and 90°) of vlave opening angle. Measurement by the PIV(Particle Image Velocimetry) was conducted to investigate the flow characteristics of butterfly valve about discharge of dam.. Flow behaviors such as instantaneous and time-mean velocity vectors are investigated each cases. The results from flow visualization using PIV through the video which do not contain a cavitation phenomenon was confirmed in accordance with the valve opening. Performs valve opening and the flow properties of the Karman vortex generated by the frequency analysis is 90° was calculated the frequency of the butterfly valve applied to the actual dam. Butterfly valve for the emergency discharge valve is susceptible to cavitation caused by the valve opening 90° and repeat the cycle in the valve side of the vortex emission system is a high possibility of damage due to fatigue.