Defect Detection And Analysis Of Xuanning Natural Gas Pipeline In Shandong Province

At present,the safety form of oil and gas pipeline network in China is severe,especially since the "11.22" accident in 2013,the State Council has listed and supervised a number of major pipeline safety hidden danger control projects,and the safe operation of pipelines is particularly important.However,some pipelines in Shandong pipeline network have not been pigging and internal inspection since they were put into operation.There may be impurities such as construction residues,water,iron oxide,dust and other impurities in the pipeline,which will cause certain damage to the pipeline due to impurities and external factors.At present,the integrity of pipeline ontology cannot be known,and there are certain safety risks in the pipeline.Therefore,it is urgent to find out the current situation of pipeline defects in Shandong pipeline network through the analysis and evaluation of pipeline defects in pipeline internal inspection and repair.In this paper,according to the actual situation of Xuanning pipeline,the defects of the pipeline are studied.First of all,select a reasonable detection method,determine the pipeline comprehensive inspection needs pigging,deformation detection and metal loss detection,and select the detection equipment of the three links.After the completion of the model selection,the equipment is put into operation on site,and the detection equipment is optimized to ensure that the detection equipment is put into operation normally,without abrasion and jamming.The accuracy of the test results was verified,focusing on the defects of Xuanning natural gas pipeline,and the pipeline defects were statistically analyzed,including metal loss,deformation and weld anomaly.Through comparison,it is found that the main defect type of pipeline is metal loss,and the proportion of pipe deformation and weld abnormal relative metal loss is very small.The metal loss mechanism of pipeline is studied and analyzed,which is mainly caused by corrosion.The main causes,direct causes and accelerated corrosion reasons were analyzed.Finally,the residual strength assessment of metal loss based on pipeline defects is carried out,and suggestions for pipeline repair are put forward.It is of great significance to slow down the corrosion of gas transmission pipeline,prolong the service life of pipeline and ensure the stable operation of gas transmission pipeline.