Characterization Parameters and Laws of Corrosion Hazard of Gas Pipeline without Cathodic Protection

A statistical analysis was conducted on the distribution of pipeline ground potential of a leaking gas pipeline in a certain gas company from 2016 to 2020. At the same time, on-site corrosion inspection piece embedding tests were conducted, and corrosion rate data of the inspection piece and corresponding 5 parameters such as the on/off potential, current density, on/off potential difference, environmental resistivity, and surface potential gradient of the inspection piece were obtained. Through data analysis, the correlation and related laws between each parameter and corrosion rate were obtained. The results showed that the correlation between current density and pipeline corrosion rate was the best, with a Pearson coefficient up to 0.95. Without inspection plates, the pipeline to ground potential index could be used to evaluate the corrosion risk of pipelines.