Study on quantitative risk assessment of girth weld failure of natural gas pipeline based on reliability

Abstract

In order to avoid safety accidents caused by the failure of welding girth weld of long-distance gas pipeline, carry out quality investigation of girth weld of in-service pipeline, and perform quantitative risk assessment based on reliability for girth weld with difficulty in excavation, to effectively improve the effectiveness and economy of excavation point selection. In this study, using the probability-based weld structure failure prediction method through girth weld X-ray inspection results during the construction period, calculate the probability of fire and explosion due to leakage/rupture of girth welds in the natural gas pipeline and the impact range based on the basic risk evaluation information such as external environment and personnel distribution in the area of the pipe section where the welds are located. Identify excavation plan based on the evaluation results, and propose effective risk mitigation measures for nonexcavation sites. In the end, practical application cases are listed.