應用MI來改善包覆層下腐蝕(CUI)問題

Abstract

Equipments and piping systems were insulated for heat conservation, process control, personnel protection, condensation control and fire protection. The failure cases were increasing due to corrosion under insulation (CUI) for aged plants. The affected materials include carbon steel, alloy steel and stainless steel. This is a common and old problem for various industry plants, e.g. refinery, petrochemical, power, steel manufacture and chemical plant. CUI had caused a serious safety problem and significant loss of production. In this paper, CUI related technology and field applications were developed including risk based inspection, inspection and fitness for services by MI programmer. Finally, the CUI prevention strategies was proposed from the standpoints of design, manufacture installation maintenance and inspection. The results revealed that serious wall thinning of equipments and piping due to CUI can be found by applying MI programmer to establish the CUI inspection and mitigation approach, and to carry out the field application. The potential leakages were effectively prevented to reduce accidents and the relevant economic loss as a result of unplanned shutdown by achieving through the application of three I (MI, and RBI, and API) to systematically improve and control an I (CUI) issues.