Failure Analysis and Experiment of Shale Gas Gathering Pipeline

This paper explores the reasons for the perforation failure of the shale gas gathering pipeline in the E Gas Mine and proposes preventive measures. EDS experiment found that the corrosion products were mainly Fe₂O₃, FeS, and FeCO₃. Shale gas contains 24.908 g/m³ CO₂ and 0.384 g/m³ H₂S, and formation water contains 20.445 g/m³ Cl⁻. Therefore, CO₂/H₂S corrosion has occurred in the pipeline, and Cl⁻ exacerbated localized damage to the material matrix, accelerated corrosion of the pipeline. The base material was more corrosion resistant than the weld, but the weld was more erosion resistant than the base material. The CFD simulation results found that the main reason of pipeline erosion is that, the shale gas contains grit and the gas volume exceeds the designed gas volume. So, the perforation failure of the pipeline was a result of both corrosion and erosion, and the effect of erosion is stronger than that of CO₂/H₂S corrosion on the pipeline.