Evaluation of Various IMM/IC Coating Systems in Terms of CUI Protection

Abstract In Oil & Gas facilities projects, coating system selection of bulk valves is challenging for EPC contractor s to manage because their quantity is extensive and they are installed in each specific situation. IMM (Inert Multi Polymeric Matrix) / IC (Inorganic Copolymer) coatings, hereinafter referred to as IMM, which can be applied under various situations are anticipated to be applied for the bulk valves. Several types of IMM paints have been introduced to the market. In the previous paper(AMPP-2024-20414), it was reported that corrosion protection performance of the IMM test panel decreased when subjected to natural weathering test and salt spray after they are heated to high temperatures.1 In this paper, corrosion protection performance of the IMM test panels for CUI were evaluated. Test panels of IMM coating system were prepared from three different manufacture brands in target dry film thickness, hereinafter referred as DFT, 250μm and with or without heat curing. Corrosion protection performance of test panels in CUI situation was tested by CUI accelerating test, and evaluated by degree of rust, blister, flaking, crack, and EIS (Electrochemical Impedance Spectroscopy). Test results differ depending on each brand. Some IMM test panels indicate cracking, flaking, rust during cycle test. The overall trend is that test panels without heat curing indicate better CUI protective performance rather than with heat cured panels. In conclusion, from the previous report and this experiment, corrosion protection performance of IMM test panel tends to decrease when exposed to high temperatures in many brands.1 Therefore, ISO(1) 19277 qualification procedure which includes heat conditioning requirement before ambient test/CUI accelerating test should be recommended to evaluate IMM performance.