Evaluation And Integrity Management Corrosion Protection For Buried Steel Pipe

With the increase of buried pipeline facilities and the diversities of the laying environment,buried gas pipeline is affected by various factors,which woul d lead to gas leaks.Corrosion is one of the main reasons for the failure of buried gas steel pipe.By detecting the corrosion of buried gas steel pipe and the classifying risks and the reinforcing integrity management,the risk of gas leak would reduce,w hich would ensure the safe operation of the pipe network system.This article described the main reason of the buried gas steel pipe corrosion and anti-corrosion technology;and analyzed the pipeline external corrosion detection principles.Taking the buried gas steel pipe of a gas company in Jinan as the research object,the representative pipe sections are selected,and the pipeline external corrosion is evaluated.Through the buried steel pipe corrosion detection comparison of various types of methods,we chose the pipeline current map and Pearson leak detector to detect the leakage of the coating.We give the evaluation of the external corrosion of pipeline by following factors: the detected depth of buried pipeline,leaking point of the coating,insulation resistance of coating,potential shift caused by stray current interference,pipeline cathodic protection potential,soil resistivity etc.We also put forward the improvement measures to ensure the safe operation of the pipeline.We use pipeline stress analysis software,build the pipeline system model,analyze the stress state of buried pipeline,obtained the pipe stress concentration point.Through the multiphase flow simulation,combined with the laboratory coupon test,and the non-contact pipe magnetic detection equipment for the pipeline corrosion detection,and by the excavation check,we obtained the corrosion rate of main pipeline in hydrogen sulfide environment.Through the establishment of the integrity measures for the inspection and the evaluation process of buried steel pipe corrosion,about the detection of the problem,We improve the integrity of the measures,strengthening the management of protection,using scientific and reasonable methods to establish effective procedures to build integrity management of buried gas steel pipe,to ensure the operation of buried gas steel pipe safe and reliable.