Corrosion behavior study and failure time analysis of X65 pipeline steel in near-neutral soil

Corrosion is an important cause of oil and gas pipeline failure, and with the continuous development of social economy and the rising demand for energy, the problem of corrosion of oil and gas transportation pipelines is becoming more and more obvious. The finite element model of axial section of X65 pipeline steel is established by electrochemical parameters obtained from experiments in near-neutral soil simulation solution, and the corrosion defects produced by the effect of uneven microstructure distribution are analyzed. Based on this, the behavior and failure time of X65 pipeline steel corrosion under pressure and electrochemical coupling are further investigated. The results show that there is a significant effect on the corrosion of X65 pipeline steel between different defects. In addition, the corrosion at the defects of X65 pipeline steel under double defects will be weakened compared with single defects, and the corrosion at the defects of X65 pipeline steel under triple defects is the most serious. This study mainly analyzes the effect of single and multiple defects on the corrosion behavior of X65 pipeline steel, which provides a reference for the corrosion protection and pipeline safety of X65 pipeline steel under near-neutral soil.