Selection of External Coatings for Northern Pipelines: Laboratory Methodologies for Evaluation and Qualification of Coatings

In the near future, the construction of northern pipelines for transmission of natural gas will begin in North America. Construction in the harsh northern climate, with temperatures as low as −45°C, and remote location will impose unique challenges with respect to protective coatings. It is critical that the design of coatings be adequate to protect the pipelines under long-term, severe environmental conditions, including the extreme climatic conditions that will apply in the North before the pipe is installed and operation begins. There are many quality coatings from which to choose for application on new pipelines. The main issue is in understanding how to select and use coatings on pipelines in new regimes (e.g. Northern pipelines), which may operate in a different environment than do existing pipelines. Uniform, standardized tests that would simulate the conditions during construction and operation of Northern pipelines will allow external pipeline coatings to be selected with confidence regarding anticipated long-term performance under operational conditions. Selection of mainline coatings is important, but there is also a need to focus on field-applied coatings for both repairs and joints. Methodologies and standards that are available to evaluate coatings are reviewed in this paper.