100% Solids Epoxy Performance Testing: Adhesion Testing
Measuring the adhesion of the protective coating to the underlying surface is made at regular intervals in different sections of the structure (i.e. crown of the pipe, along the wall or invert). The adhesion is measured in accordance with the American Society for Testing And Materials (ASTM D7234). The project engineer will monitor and evaluate any areas of inadequate adhesion. Continued tests performed in the area will determine the extent of the deficiently bonded area. Repairs will be made by the applicator in strict accordance with the manufacturer recommendations.
When the coating is removed completely from the substrate yet remain adhered to the adhesive on the dolly, test results are considered 100% valid. If only a portion of the coating is removed, the results will be analyzed, including fracture pattern which will determine the following: cohesive properties of the coating and adhesion properties between dolly and adhesive, between adhesive and coating, between distinct coating layers, as well as between the coating and substrate.
A binding agreement regarding "inadequate adhesion" between owner and applicator is advised prior to adhesion testing. Please note that there are a number of variables that play a part in the analysis and testing of adhesion.
