Correlation functions and their application in pipeline leak inspection

In order to achieve detection to certain physical quantities, self-correlation and interrelation functions are used in correlation detection technology, which can be used in pipeline leak inspection, especially in negative pressure wave and flow leak inspection. Combined with the characteristic and principle of correlation functions, their application principle in pipeline leak inspection and the method of leak location calculation are analyzed, and location method of leak detection for oil pipeline is proposed. This method uses acoustic sensors to detect sound waves generated by the leakage of vibration signals and relevant technology to determine the delay of different output signals, and then locate the leak point according to the distribution of sensors and acoustic transmission speed. Sampling time and threshold directly affect the sensitivity and reliability of leak inspection. Noise elimination is necessary before correlation function calculating to avoid shielding of leakage signals. The current inspection technology is only applicable for location of sudden and rapid leak, but not for slow leaks in actual pipeline engineering.