Laboratory Methodologies to Evaluate the Compatibility Between Mainline and Girthweld Coatings

摘要

The compatibility between thirteen girthweld coatings with four mainline coatings have been evaluated using cathodic disbondment (CD), impact, flexibility, pull-adhesion, and hot-water immersion tests. The test panels had both mainline and girthweld coatings and were prepared by removing a portion of previously applied mainline coating and applying a girthweld coating. Before performance testing, the panels were exposed to four different temperatures for four months. Compatibility between thirteen girthweld coatings with four mainline coatings has been established based on the test results. The importance of using panels containing both mainline and girthweld coatings has been emphasized. Some common characteristics of evaluating mainline and girthweld coatings have been identified. The importance of quality control especially in the surface preparation has also been highlighted.