Analysis of pipeline leakage alarm threshold in nuclear power plant

Piping cracks are widely spread in the nuclear power plants, which affect the safety and economy of reactors. The leak before break (LBB) concept detects the leakage through cracks and afterwards takes human intervention, to avoid break and rupture of pipes. As a precondition for the application of LBB technology, a constant leakage monitoring system is necessary. The leakage monitoring system based on temperature and humidity monitoring method can be used for leakage location and quantitative analysis, but how to set a reasonable alarm threshold directly affects whether the system can be put into use normally. This paper mainly analyzes and verifies the change trend of temperature and humidity of when leakage occurs at different positions under steady-state condition, which provides basis for setting reasonable alarm threshold of temperature and humidity sensor.