Corrosion Under Insulation (CUI)

What is Corrosion Under Insulation (CUI)?

What causes Corrosion Under Insulation (CUI)?

How does Nansulate® Prevent Corrosion Under Insulation (CUI)?

THE PROBLEM: Corrosion Under Insulation is a multi-billion dollar problem that destroys expensive industrial infrastructure and causes continuous scheduled manufacturing plant and facility downtime to conduct inspections for failure and unexpected downtime when equipment failure occurs.

It is exactly what it sounds like… corrosion of pipes, tanks, and equipment which occurs under the pipe insulation and, in many cases, is caused by insulation. The root cause is simple: At the interface between the pipe insulation and the substrate to which the insulation is applied there is a temperature differential. Regardless of how tight a pipe insulation material is wrapped around, or applied to, the substrate there is a space where the temperature makes a quick change from higher to lower and that causes a release of moisture… commonly referred to as condensation… and that causes rust and corrosion.

TWO IMPORTANT PIPE INSULATION CONCEPTS TO UNDERSTAND:

It is important to note here that “warm” and “cool” or “hot” and “cold” are relative terms. If “hot” is a pipe that is 200°C and the surrounding environment is 100°C, although we would consider the 100°C to be hot, in the context of the thermal system… it is cool.

The most basic law of heat transfer is that heat always flows to cold. Warmer air can hold more moisture than colder air. When the warm air is quickly cooled by its encounter with the pipe insulation which reduces the rate of heat transfer… moisture is released or, to put it another way, condensation occurs.

Heat transfer is not necessary correlated to air movement. Heat energy moves through matter… metal, insulation, air, etc. An analogy is a wave rolling into the beach. What you see is not the actual water moving to shore (as can be demonstrated by the fact that a boat or a piece of floating debris does not move forward with the wave… just up and down as the wave passes underneath). Heat “waves” of heat energy pass through material the same way and the temperature of the matter is lowered as the rate of heat transfer (or the speed of the heat “wave”) is reduced. Therefore the temperature of the air directly adjacent to the heat source (a steam pipe at a factory OR the outside air around a cold pipe) is higher than the temperature of the air adjacent to the insulation. It doesn’t matter how small the distance is between the insulation and the substrate, there is ALWAYS a temperature differential.

This layer of moisture remains trapped and it is not difficult to deduce what happens when you keep a constant layer of moisture trapped against a piece of metal. It corrodes.

How does Nansulate® Prevent Corrosion Under Insulation (CUI)?

THE SOLUTION: The effectiveness of Nansulate® in preventing Corrosion Under Insulation (CUI) while providing excellent thermal insulation was difficult to create… but it is easy to explain.

First:

Hydrophobic refers to the tendency of a substance to repel water. The nanocomposite which constitutes approximately 70% of the dry film thickness of Nansulate® is highly hydrophobic.

Due to the fact that Nansulate® adheres directly to the substrate being insulated, it coats the substrate with the hydrophobic particles which act to continuously repel any attempt at moisture build-up and no moisture means excellent rust prevention and corrosion protection.

Second:

Nansulate® adheres directly to the substrate, bonding with it. There is no… and we mean not even microscopic… space for air and the life giving oxygen that rust needs to grow.

PLUS: The hydrophobic performance characteristic of the nanocomposite in Nansulate® also repel moisture from the coating itself, effectively creating a moisture free barrier against the pipe or tank or piece of equipment being insulated. The severe service environments of coastal or offshore facilities, with the constant salt air and salt spray can destroy equipment fast. The hydrophobic performance qualities of Nansulate® repel the attempt by salt water to penetrate through to the substrate, preventing rust and corrosion caused by the severe service conditions encountered by petroleum refineries, supertankers, and many other industrial facilities vital to the economies of the world and critical to the resource supply chain.

Intellectual Property Policy: Industrial Nanotech, Inc. and our partners in nanoechnology research vigorously defend the rights to our intellectual property and immediately pursue all available remedies against any and all attempts at infringement.