Investigation and comparison of effects of mineral wool and a water repellent insulation on CUI. Drain holes and their ability to reduce CUI was evaluated. The susceptibility to CUI of carbon steel was investigated at 80 °C using a newly developed test rig in a controlled environment (25 °C and 50 %RH).
Many types of thermal insulation materials are used in oil and gas plant facilities. Recently new materials have been developed to prevent corrosion under insulation (CUI) and even the conventional materials have been improved their properties to provide better protection.When designing a plant measures to prevent CUI are studied when verifying the materials of construction determining the protective coatings systems and selecting thermal insulation and jacketing materials. Measures to prevent CUI should not be considered separately for these but rather together as a total system. Recently though while protective coatings have been studied by users coating manufacturers and independent organizations such as testing laboratories engineering firms and consultants there has been little investigation of the ability of thermal insulation materials themselves to prevent CUI.In this study the ability of various thermal insulation materials to prevent CUI in a simulated severely corrosive environment were examined. The factors influencing CUI prevention or aggravation were identified based on which it was recommended that these factors be considered when selecting thermal insulation materials during the design of a plant. As a summary of this study experiences of design of plants and related other CUI studies effective ideas relating to protective coatings thermal insulation and jacketing materials for preventing CUI will be shared.