Consideration is given to corrosion monitoring of the outside surface of walls of main pipelines. Results obtained by using the above method were checked under laboratory and field conditions. The procedure for measuring the rate of soil corrosion of the pipeline metal was optimized. Measurements were made using the two- and three-electrode measuring diagrams under potentiostatic and potentiodynamic conditions. The method based on measuring corrosiveness of soil for a pipe laid down at different levels, and the rate of residual corrosion of the pipeline metal was developed to characterize the pipeline corrosion
state. The special software was developed to determine the ba, bc and icorr constants on the basis of analysis of the polarization curve equation. The method allows for setting a range of possible values for
each of the parameters. Good agreement between experimental and calculated data is indicative of fitness of this software for purpose.
Standards and instructions are used as the regulatory documents to ensure the maximum degree of protection of pipelines operating in different climatic zones and subjected during operation to the
effect of different technogenic factors (crossing with railways and motor roads, electric transmission lines, other pipelines). The offered technology for electrochemical monitoring of active pipelines is a complex technology and includes the following measurements to be made continuously or periodically:
• susceptibility of the pipe and welded joint metal to the most dangerous types of corrosion: SCC, pitting, spot, crevice and contact corrosion;
• variations in corrosion resistance of the pipe metal under the effect of service factors;
• corrosion activity of soil with respect to the pipe metal under a corrosion potential at different levels of position of the pipeline;
• determination of the rate of residual corrosion of the pipe metal at insulation coating defects;
• distribution of polarization potential over the surface of earth along the pipeline route.
Keywords: corrosion monitoring, corrosiveness of soil, pipeline, residual corrosion of metal.