Advanced Polymerics, Inc. has announced new test data confirming that its patented Permacorr coating effectively mitigates corrosion under insulation (CUI) – one of the most costly and persistent maintenance challenges for carbon steel assets worldwide.
CUI occurs when moisture becomes trapped beneath insulation or jacketing on hot equipment, causing aggressive corrosion and chloride stress cracking in carbon and stainless steels. Studies show that corrosion rates increase by approximately 30% for every 10°C temperature rise, and up to 40% of piping maintenance costs in refineries, and solar and chemical plants can be attributed to CUI-related degradation. In fact, CUI is a $276 billion (€240 billion) problem in North America alone.
Permacorr’s chemically bonded phosphate ceramic technology addresses the CUI problem by forming a molecular bond to the steel surface rather than a physical one. This permanent chemical interaction passivates corrosion cells, effectively protecting the substrate against oxygen and moisture. Even if microcracks form from thermal cycling, the underlying bond remains intact, and corrosion cannot start.
In the industry-standard Vertical Pipe (Houston) Test, which exposes coated and insulated pipe sections to cyclic wet/dry salt spray and elevated temperatures, Permacorr demonstrated no blistering, cracking, or corrosion after extended exposure. By contrast, epoxy-phenolic coatings typically show severe degradation after a few cycles.
Permacorr also withstood a six-month cyclic boiling-water test (8 hours immersion, 16 hours dry) with no observable deterioration, conditions that simulate the 90–120°C temperature range where condensation, vapor, and liquid water coexist and corrosion rates peak.
API president Stephen Jewitt comments: ‘Asset owners have long faced a trade-off between corrosion resistance, heat tolerance, and cost. Permacorr removes that compromise. It delivers high-temperature CUI protection, faster application, and significantly lower total lifecycle costs.’
Because Permacorr is water-based, VOC-free, and non-toxic, it supports sustainability goals without jeopardising performance. It also does not interfere with non-destructive testing – an important advantage for operators using ultrasonic or radiographic inspection methods. The inorganic, cementitious nature of Permacorr provides thermal stability up to 250°C (480°F) while maintaining full adhesion and chemical resistance. Only a single coat [at 10–15 mils (250–375 µm)] is required, applied via plural-component spray. The coating’s self-sealing behavior also minimizes surface preparation requirements and allows application over flash rust, reducing both time and cost of application.
Permacorr is suited for insulated tanks, steam lines, process piping, and pressure vessels operating up to 250°C, including facilities in the oil and gas, petrochemical, biopharma, and power generation sectors.
‘CUI is one of the few corrosion mechanisms that still catches operators by surprise,’ Jewitt adds. ‘Permacorr provides the peace of mind that comes from knowing the coating system is working even when you can’t see it.’
