공기구동밸브 안전중요도 결정 및 범주분류 방법론 개발

다국어 초록 (Multilingual Abstract)

POV(Power-operated valve) consists of actuator that produces power and valve. Power-operated valves are classified into MOV(motor-operated valve), AOV(air-operated valve), extra valves such as solenoid valve according to actuator type; gate valve, globe valve and butterfly valve according to valve type. Since some POVs in US had been failed to perform a safety function, US NRC had recommended to verify the operability of POVs through Generic Letters. Korean regulatory organization also recommended to perform the safety evaluation for POVs.
This paper describes the determining safety-significance and categorization methodology in the safety evaluation methodology for AOVs. In general, nuclear power plants have a large population of AOVs with varying degrees of safety-significance. Therefore, to perform an effective AOV evaluation, it is essential to establish a method to clearly identify those AOVs with the highest contribution to safe plant operation.
The AOV evaluation program utilizes risk-informed methods to determine the in-scope AOV population. It is expected that utilities will develop a plant specific AOV evaluation program. There are many various type of Nuclear Power Plants in Korea. Through this study, it will be provided all Korean NPPs applicable methodology for determining safety-significance and categorization of AOV.
The safety-significance classification shall involve a blended process of risk ranking and plant expert panel evaluation. AOVs are placed in one of two categories (Categories 1 and 2) based on their contribution to safe plant operation and/or accident mitigation. The requirements of the AOV evaluation are dependent on the category in which each AOV is assigned. These categories determine the extent of design review and testing activities to be performed.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 평가대상 AOV 선정 방법
• 3. 안전중요도 결정
• 4. 결론
• 참고문헌