Selected types of corrosion degradation of pipelines

The paper deals with corrosion degradation of gas pipeline. Pipelines play very important role as means transporting gas media over long distances from producers to end-users. Gas pipelines present a risk of potential corrosion degradation that can result in their failure. Corrosion on internal surfaces of steel pipes takes place in CO2, H2S, H2O and chloride environment. Degradation of steel results in loss of mechanical properties, reduction in thickness and ultimate perforation and failure. Corrosion is the electrochemical process that involves the fl ow of electrical currents on a micro or macro scale. For corroding steel, the anodic and the cathodic reactions produces the electrochemical cell. Corrosion protection of internal pipeline surface is based mainly on chemical composition of gas and the use of inhibitors. Corrosion protection of the external steel surface of the product line involves coatings and cathodic protection.