Comparison method on internal inspection data of long distance pipeline

In this paper, the value of the internal inspection data of pipeline was tapped sufficiently to improve its utilization rate. Based on domestic and foreign comparison methods on internal inspection data of long-distance pipeline, the possible problems in the process of the key point alignment were analyzed and their solutions were provided. And finally, the steps of the key point alignment were summarized. In the cases of key point alignment (e.g. weld, elbow and valve), the defect matching between two-round internal inspection data (including erosion, manufacturing defect, dent, crack and so on) is mainly based on three key location factors, i.e., relative distance, clock orientation and surface location. According to the growth rate, defects are divided into four types, i.e., active defect point, inactive defect point, new defect point and other defect points. After two-round internal inspection data of a certain long distance pipeline was compared, the locations of defects were determined and the growth rate of defects was estimated. The research results provide reference for pipeline operation units to make decisions.