To help address this problem, testing programs were initiated to identify primers, coatings, and topcoats that would perform better and for longer periods of time in this severe environment. It was found that the key to solving CUI in the long-term is to identify a primer that can survive the exposure and work well with the insulation type material that did not promote moisture entrapment. As a result of the testing, an innovative approach using a combination of coating systems to provide protection and insulation has been used as a successful deterrent to CUI. Combined together, the coating systems protect, insulate and make inspection easy for areas under 350°F (190°C) or below.
The system includes both using a good primer system and a thermal insulation coating. Using an inorganic zinc type primer (works very well in this system as there is little sacrifice and it adheres well in high-temperature environments) or glass flake epoxy as the primer coating over carbon steel substrates can ensure a compatibility, in most cases, with thermal insulating coatings. These primers provide excellent adhesion, as well as a tough barrier when applied directly to steel. They also have the ability to handle higher temperature applications without de-bonding. They must be used in conjunction with the second component to provide long-term performance.
The second component is the use of a thermal insulating coating. Mascoat has pioneered, developed and engineered a coating specifically designed to provide protection with insulating like qualities. Mascoat Industrial-DTI has been used for many years as a component in this type of system. The insulating coating is used to reduce the substrate temperature or provide insulating qualities in an easily applied format. By combining these two systems, a successful long-term solution is achieved as well as providing other unique advantages.