Study on the Methods of Cycle Determining for an Urban Gas Pipeline Detection

In the early and mid-stage of a pipeline in using, the gas pipeline detection-cycle (or detection of life) when the gas-pipeline still in a lower level of risk can use a relatively fixed cycle for pipeline detection, but when the pipeline puts into use up to a certain age, especially in the late use of the pipeline, the probability of the occurrences of pipeline accidents is in a trend of gradually increased with the extension of the time. At this time, if a relatively fixed detection cycle continues to be used to detect the gas-pipelines, it will undoubtedly increase the risk of safe operation and management. Based on this, from the security risk management point of view, this paper have researched how to determine the urban gas-pipeline network detecting cycle that in a certain reliability level. Focusing on how to determine the detection cycle when the gas-pipeline was in the latter part of its use life and having a higher accident rate, we have given a dynamic detection cycle approach with time-varying.