Abstract: The oil pipeline leaking accident occurs for many reasons.In order to reduce the loss which the accident results in,the leakage and leaking position should be discovered promptly.In this paper,the basic theory of applying negative wave to detect leakage is introduced,then the characteristic of pressure signals singularity and the different characteristics between signals and noises are analyzed based on their wavelet transform,the sudden change signal wavelet transformation mold maximum value increases along with the criterion increases,but the noise wavelet transformation mold maximum value reduces along with the criterion increases.Therefore,the leaking point position can be figured out by using the time difference and propagation velocity of the negative pressure wave,which may arrive at the both ends of the oil pipeline.The case study indicates that,the wavelet transform method of transformation can be used to accurately withdraw the sudden change value of the transient negative pressure wave,thus the leakage location can be detected.

Key words: oil pipeline, leakage, detection, wavelet transform, algorithm 