Coating Resistance Measurement on Buried Steel Gas Pipelines In Municipal Areas

"Coating Resistance Measurement on Buried Steel Gas Pipelines In Municipal Areas"

 A. Koopaee, Aghajani, A. Saatchi

 Material Performance, June 2009

Abbstract :

Electrical coating resistance (ECR) has emerged as a significant test method for performing coating resistance measurement on buried steel gas pipelines in municipal areas. The ECR test method measures the electrical resistance of a specific section of a buried pipeline coating located between two isolation joints or flanges. The electrical resistance of the coating is expressed as the resistance per average square meter of the material. The measured coating resistance is affected by the soil resistively in the area of the pipeline being tested. It is observed that the same quality coating yields a lower ECR in low-resistivity soil in comparison with high-resistivity soil. This factor needs to be considered when comparing ECRs of coatings on pipelines in different resistivity soils. The ECR test method can also be used to assist in conducting pipeline integrity investigations.