Stress-corrosion is a factor that shapes the operational status of the trunk pipelines. Being a complex and ambiguous phenomenon underlain by various environmental conditions, stress state, structure and metal-specific properties, stress-corrosion is known as one of the most dangerous types of damages affecting pipes (Figure. 1). According to recent findings, apart from linear part of trunk pipelines, underground flowlines (compressor stations process pipelines) are also affected by stress-corrosion. In-pipe inspection is somewhat difficult to conduct on compressor station flowlines as soon as the pigs can not be run, therefore specific corrosion control and pipeline maintenance methods need to be developed. These days, Gazprom is implementing a plan package to mitigate risks of failures due to stress-corrosion. The root causes of stress-corrosion have been detected; a pipeline maintenance methods have been adopted (including methods of inspection, evaluation of strength properties and scope of repair); a pipeline re-insulation program has been launched (under this program a large variety of coatings have been developed to ensure reliable corrosion-proof operation of pipelines).
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