Classification of Polymeric Coatings for the Protection of External Surfaces of Buried and Submerged Pipelines

Abstract The combination of polymeric coatings and cathodic protection (CP) has proven to be both effective and efficient in mitigating corrosion. Over the past century, a wide range of coating technologies has been developed. This paper introduces qualitative criteria for classifying coatings into six distinct categories: Good coatings Poor coatings Shielding coatings Incohesive coatings Blister-forming coatings Hydrogen-susceptible coatings The data supporting this classification is presented to help users understand the strengths and limitations of the approach. Additionally, the paper discusses ongoing standardization efforts aimed at developing - and potentially refining - this classification system. Key initiatives include: Development of coating selection guidelines by the AMPP 21618 Task Group Consolidation of various ASTM cathodic disbondment (CD) test standards into a unified standard Coordination of ASTM interlaboratory studies (ILS) to establish the precision of CD tests across different coating types