Specific Features of Corrosion of Heating Network Pipelines Made of 17G1S Steel

It is shown that the fluctuations of internal pressure at an operating temperature of 40°C insignificantly affect the rate of pitting corrosion in the pipelines of heating networks made of 17G1S steel. However, at a temperature of 80°C, this rate becomes more than twice higher. The corrosion process accelerates as the working pressure increases and becomes more pronounced in the case where the working stresses periodically increase up to the level corresponding to the pressure of hydraulic tests. The rate of uniform corrosion of the pipeline walls increases with temperature and the accumulated strain. After long-term contact with corrosive media at a temperature of ~ 80°C, the pipeline metal with residual strains of 1–3% becomes low-resistant according to the corrosion-resistance scale of metals, which increases the risk of fracture of the pipeline. After long-term operation in the mode of gradual accumulation of plastic strains, the susceptibility of pipelines to corrosive fracture increases with temperature.