Intergranular stress corrosion cracking of steel gas pipelines in weak alkaline soil electrolytes

Abstract The paper presents an overview of the main types of stress corrosion cracking (SCC) of pipeline steels under operating conditions of high-pressure buried gas pipelines. Up to the present time, there have been cases of transgranular cracking in gas pipelines in near-neutral pH soil electrolytes in Russian territory. The present work studies fragments of pipes containing cracks as well as soil samples at the excavation sites of gas pipelines running through the territory of the Astrakhan region. It was found that the cracks formed as a result of SCC of pipe metal and are of intergranular character of propagation. It is also established that the chemical composition of the soil along the gas pipeline differs from the previously studied compositions of corrosive environments that encourage the development of intergranular SCC of pipeline steels.