Demonstration of Thermal Barrier Coating System Used in Heat Distribution System Manholes

Heat distribution systems (HDS) are an integral part of military facility and installation infrastructure. Inside the HDS manholes, pipes and appurtenances are often exposed to a high-temperature, high-humidity environment. This corrosive environment can cause moderate to severe corrosion of pipes and appurtenances in a relatively short time, resulting a significant reduction in system energy efficiency, reliability, and service life. In order to counteract these types of corrosive effects, two projects were initiated to demonstrate an innovative coating system consisting of a corrosion-resistant primer and a thermally insulating ceramic topcoat. The first application was performed at Fort Jackson, SC, on a low-temperature system. The second application was performed at Redstone Arsenal, AL, on a high-temperature HDS.

In addition to providing corrosion protection, part of the initial intent of this work was to reduce the temperature inside the manholes in order to reduce the corrosivity of the interior environment. This paper describes the initial results of both laboratory experiments and field performance of this coating system. The results reported here pertain both to the performance of the coating materials and lessons learned about application in the field on operating HDSs.