Abstract
Advancing technologies for pipeline construction techniques and increasingly severe operating parameters present challenges for pipeline coatings. Multi-layer coatings have evolved to increase the mechanical toughness of the system, to provide corrosion protection at elevated temperatures, to provide specific surface textures, to provide a foundation for insulation systems, and to accept the rigors of specific construction techniques. Qualification test methods must give assurance that the basic system has the ability to survive the operating conditions after construction. Quality control (QC) testing must provide assurance that acceptable performance is consistently achieved throughout the course of mill and field application activities. Proper selection of test methods and proper interpretation of test results are essential components of comprehensive pipe coating and construction projects. This paper begins with a brief discussion of essential properties of all pipeline coatings, and a listing of multi-layer systems designed to meet specific needs. It then focuses on special considerations regarding application parameters for multi-layer systems that use fusion-bonded epoxy as the primer. These parameters determine long-term performance. A new interpretation of the simple water soak test can be a valuable tool in quality control testing.
