抄録
Flow Accelerated Corrosion (FAC) of carbon steel (CS) piping is one of main issues in secondary system of Pressurized Water Reactor (PWR) nuclear power plant Wall thinning of CS piping due to FAC increases potential risk of pipe rupture, cost for inspection and replacement of damaged pipes In particular, corrosion products generated by FAC of CS piping brought steam generator (SG) tube corrosion and degradation of thermal performance, when it intruded and accumulated in secondary side of PWR. ^(1) Therefore, we estimated an applicability and effectiveness of Oxygenated Water Chemistry (OWC) as a new approach to FAC suppression for PWR secondary system by experiment in laboratory and demonstration test at Tsuruga-2 (1160 MWe PWR, commercial operation started in 1987). ^<(2)(3)> Based on this result, OWC has been applied to condensate system in Tsuruga-2 from Jan 2011 And, to evaluate the FAC mitigation effect of OWC, wall thickness of actual condensate piping in Tsuruga-2 after OWC application was measured by continuous monitoring system, using high-temperature and high-resolution ultrasonic probe In this paper, behavior of actual wall thinning rate of condensate piping in Tsuruga-2 under various pH and DO concentration is discussed
