Research on gate valve gas internal leakage AE characteristics under variety operating conditions

This paper researched gate valve gas internal leakage acoustic emission characteristics under the operating conditions of different pressure, internal leakage rate and internal leakage size. Firstly, introduced structure of gate valve, the main reasons of internal leakage and acoustic emission detect technology. Then, established gate valve internal leakage experiment system, to realize the internal leakage under the operating conditions of different pressure, internal leakage rate and internal leakage size. Finally, on this basis, with acoustic emission non-destructive detection theory, put forward gate valve internal leakage AE detect experiment under variety operating conditions, analyzed and compared internal leakage AE characteristics under different operating conditions, such as pressure differences between 0.1MPa and 0.2MPa, internal leakage rate between 0Lmin and 80Lmin, internal leakage size between 0.5mm and 1.5mmm. The research results show that gate valve internal leakage can be represented by AE signal amplitude, ASL and energy. The three parameters may have linear variation or index movement under different operating conditions. The internal leakage AE parameters change slowly while internal leakage size is greater than a threshold value. These results can supply reference for gate valve internal leakage online detection and fault diagnosis in the petrochemical plant.