Multi-acoustic-wave-feature-based method for detection and quantification of downhole tubing leakage

The downhole tubing leakage of offshore gas wells is one of the important factors that cause platform fire and explosion. In this paper, relevant experimental studies are carried out on the key issue of how to detect and quantify downhole tubing leakage. Through the simulation of downhole tubing leakage experiment, the annulus acoustic detection data under different working conditions are obtained, and the characteristics of tubing leakage acoustic signal are analyzed. The detection and quantification method of downhole tubing leakage events based on multi-acoustic characteristics (MAWF) fusion is proposed. The test results show that the proposed method can effectively and quickly identify the leakage state of downhole tubing, and the accuracy of leakage event recognition is as high as 98.79%. The corresponding relationship between leakage acoustic characteristics and leakage aperture is established. The results of this study help to improve the early warning time of downhole tubing leakage.