원전 2차계통의 출력증강 운전에 따른 배관감육 영향 분석

Abstract

Piping and equipment are degraded by flow-accelerated corrosion (FAC) in nuclear power plants. FACcauses numerous problems and nuclear utilities maintain programs to control FAC. The key parametersinfluencing FAC are hydrodynamic conditions, water chemistry, and effect of materials. Recently, a nuclearutility has planned slight power uprates in Korea. Operating conditions need to be changed in the secondarysystem according to power uprates. This study analyzed the effect of wall-thinning caused by power uprates. The change of operation data in the secondary cycle is reviewed, and wall-thinning rates are analyzed inthe main lines. As a result, two phase (mixture of water and steam) lines have a greater impact than awater line under power uprate conditions. Also, the quality of steam is the most important factor for FACin two phase lines.