Valve internal leakage detection technology using fiber optic accelerometers for vibration sensing

This paper introduces a technique for detecting internal leaks in valves based on fiber optic vibration sensing in oil and gas transfer stations, where traditional electrical sensors are limited due to safety concerns. The study establishes a link between the vibration signals and the leak’s characteristics, showing that a larger pipeline diameter or Young’s modulus results in higher characteristic frequencies, and smaller leak orifices or higher pressures increase the signal amplitude. A high-sensitivity fiber optic accelerometer sensor is developed, capable of detecting vibrations from 10 Hz to 2 kHz with a sensitivity of 26.5 dB and a flatness of $\pm$1 dB. Experiments confirmed that the sensor can detect leaks as low as 75 mL/min. This method has been successfully implemented in oil and gas pipeline transfer stations, providing accurate and sensitive leak detection. Its anti-electromagnetic interference and intrinsic safety make it suitable for flammable and explosive detection environments.