Influence of Probe External Resistance on the Detection of Buried Pipeline Corrosion Through Transient Electromagnetic Method

Purposes: This paper aims to clarify the effects of the changes in detection probe external damping resistance on the transient electromagnetic method and detect the trenchless underground pipeline corrosion resolution. Methods and Process: A corrosion model was designed, multiple sets of tests were performed indoors, and online fixed points were selected and analyzed. Changes in external damping resistance were investigated to shut off the time, and the influence of the size of induction electromotive force was explored. According to the survey line profile and the relative error of test analysis, the effects of external resistance on detecting resolution were examined. Based on analysis of the influence of corrosion wall thickness change, and then compared with standard pipe groove in thickness. Results, Observations, and Conclusions: Changes in damping resistance affect the transient electromagnetic method to detect buried pipeline corrosion. Under the same test conditions, pipeline residual wall corrosion exacerbates as external damping resistance increases. The variation of residual wall thickness can determine the size of the corrosion of the resolution, and accuracy can be determined whether to confirm the requirements of the test, to identify the position of buried pipeline corrosion of high accuracy, and to provide a basis for on-site real-time detection convenient recognition. Technical Contributions: This paper confirms that using the transient electromagnetic method can be used to detect buried pipeline corrosion, and changes in damping resistance affect corrosion resolution and measure accuracy. Thus, appropriate damping resistance should be selected to obtain accurate test results.