Corrosion under insulation (CUI) poses a significant challenge to many industries – it proceeds undetected under insulation. In addition, CUI is risky, which may cause personnel injuries and, in worse cases, fatalities.
A recent study by NACE International suggests that implementing measures against corrosion under insulation could help save up to $875 billion annually. This suggestion follows research that shows that $2.5 trillion is used globally to impede corrosion under insulation.
Put simply, CUI is cost-intensive.
An example of why corrosion under insulation is such a big menace is how it affects stainless steel and carbon steel. Studies have shown that CUI is responsible for up to 60% of pipeline repairing costs and another 10% for periodic maintenance.
Stainless steel undergoes corrosion in the presence of moisture and ion penetration, more specifically, from halogens like chlorides, sulfides, fluorides, etc., as structures made using its age. Corrosion of stainless steel weakens it, and it eventually cracks because of the buildup of chlorides and other contaminants underneath its insulation.
Factors Influencing Corrosion Under Insulation
CUI adversely affects fixed equipment; for example, stainless steel pipelines transport oil and gas. Wet insulation on both carbon steel and stainless steel is one of CUI leading causes.
However, for stainless steel to undergo CUI, there must be concentrated amounts of halogens such as chloride or sulfide content. Other corrosion under insulation factors includes temperature (especially in marine environs) and moisture.
Since CUI proceeds undetected under insulation, it will eventually become evident after severe damage to critical infrastructures such as oil and gas pipelines. Routine inspection and maintenance help a great deal in fighting CUI and also help to maintain the integrity of critical infrastructure.
How Cortec Corporation Uniquely Solves CUI
Most companies try to prevent corrosion under insulation by applying coatings on the surfaces of fixed equipment. The coatings must be applied before installing the equipment’s insulation.
However, this corrosion under the insulation mitigation procedure is not entirely sustainable because it is similar to traditional coating. Corrosion works under the insulation to weaken and damage fixed equipment after compromising the insulating layer.
Cortec® Corporation has a unique solution that solves CUI by using Cortec® Vapor phase Corrosion Inhibitor (VpCI®) and Cortec® CorroLogic® inhibitors:
- VpCI® – Application of a protective layer on carbon or stainless steel surface.
- Cortec CorroLogic® inhibitors – Injecting a protective layer into existing insulation (Cortec CorroLogic®).
How Cortec VpCI® Works to Inhibit Corrosion Under Insulation
Cortec® Vapor phase Corrosion Inhibitor provides a unique solution to CUI by neutralizing halogen ions – it neutralizes the surface charge. In addition, VpCI® also displaces moisture content through a process called hydrophobic action.
It is a unique solution because the protective layer can be applied to an existing insulation layer. However, this type of layer is only suitable if temperatures do not exceed 600 °C (1100 °F).
The metal’s surface absorbs the inhibitor molecule in VpCI®. It does not matter whether the metal is in water or dry land. VpCI® molecules travel through both air and water.
In other words, VpCI® is Cortec® Corporation’s first way of impeding corrosion by applying a protective layer on the surfaces of metals. The VpCI® inhibitor still works even if the metal has an existing insulation layer.
How Cortec CorroLogic® Works in Fighting CUI
It also contains VpCI® for high-temperature cases (Cortec CorroLogic® High-Temp inhibitor).
When a Cortec CorroLogic® injectable inhibitor is injected into a metal’s existing insulation, the inhibitor molecule travels through the insulation. It then prevents corrosion under insulation by forming a thick film on the metal’s surface.
A good rule of thumb is injecting the existing insulation with the protective layer every 6m (or 20 feet). However, this solution works best if temperatures do not exceed 170 °C (or 338 °F).
Cortec CorroLogic® High-Temp inhibitor works best by using a liquid solution, for example, by mixing the VpCI® with water. Its molecules then attach themselves to the metal’s surface before applying the insulation.
Benefits of Using Cortec VpCI® & Cortec CorroLogic® in Inhibiting Corrosion Under Insulation
After in-depth research, both VpCI® and Cortec CorroLogic® inhibitors are beneficial as they offer a unique solution for CUI. The former has since prevented corrosion on metals by a rating of 30, while the latter has a rating of 15.
As such, Cortec® Corporation’s CUI products help a lot reduce repair and maintenance costs. In addition, it also reduces infrastructure downtime.
Making Sense of It All
Cortec® Corporation has a unique solution that solves CUI by using Cortec® Vapor phase Corrosion Inhibitor (VpCI®) and Cortec® CorroLogic® inhibitors:
- VpCI® – Application of a protective layer on carbon or stainless steel surface.
- Cortec CorroLogic® inhibitors – Injecting a protective layer into existing insulation (Cortec CorroLogic®).
Cortec® Vapor phase Corrosion Inhibitor provides a unique solution to CUI by neutralizing halogen ions – it neutralizes the surface charge. In addition, VpCI® also displaces moisture content through a process called hydrophobic action.
When a Cortec CorroLogic® injectable inhibitor is injected into a metal’s existing insulation, the inhibitor molecule travels through the insulation. It then prevents corrosion under insulation by forming a thick film on the metal’s surface.
Cortec® Corporation’s CUI products help a lot reduce repair and maintenance costs. In addition, it also reduces infrastructure downtime.
For more information on outdoor coatings and their use in construction check out our corrosion inhibitors for buildings article.