What is the critical temperature range for CUI in insulated low alloy steel vessels?

The critical temperature range for Corrosion Under Insulation (CUI) in insulated low alloy steel vessels is indeed from 10 to 350°F. This temperature range is significant because it is where moisture can effectively condense and create an environment conducive to corrosion underneath insulation materials. Low alloy steels are particularly susceptible to CUI in this range due to their composition and the presence of moisture.

At temperatures below 10°F, the risk of condensation is minimized, while above 350°F, the risk of corrosion decreases as temperatures rise, which often leads to rapid drying of any moisture that may be present. Thus, understanding this temperature range is vital for implementing appropriate inspection and maintenance strategies to prevent CUI, ensuring the integrity and safety of the pressure vessels.