Corrosion Control, preventative and maintenance
Corrosion control is an important factor for permanent and temporary insulation applications. While thinking about the materials used for your insulation systems it is important that you take not just the thermal properties of the materials themselves. In addition to this, you should also think about how moisture can move and stay inside or under the insulation. Moisture present in the insulation system can decrease the efficiency of your insulation, and damage the insulated structure itself. This is especially important when the piping or vessels experiences temperature cycles. Rusting of steel piping is a significant cost to the maintenance and shutdown costs for your application. If you require contamination to be prevented CUI can be detrimental. Strict quality control or applications that are in contact with food products are important examples of this.
Corrosion under insulation maintenance
When moisture condenses under insulation systems, it condenses with metal ions and salts that will react with the pipe surface, the insulation and the cladding around the insulation. Any surfaces this solution contacts will corrode, especially when under the stress of cycling temperatures found in thermal insulation systems. This is especially prevalent in applications near the coast or marine systems, due to the high salt content in the air.
The effect of corrosion on industrial operations for either oil & gas operations but also minerals processing can cause problems either upstream or downstream from the area where corrosion occurs. Stoppages in processing to both find and remove or fix corrosion under insulation are time consuming and expensive.
If you are in the oil and gas industry, leakages due to corrosion under insulation, or CUI, can contribute significantly to your overall maintenance costs. Different chemical and physical mechanisms cause this, namely galvanic, acidic, chloride or alkaline corrosion.