• The standard coating system on the piping are Not able to withstand the cyclical of HOT & COLD stress under the Insulation

• External chloride corrosion & stress cracking of Austenitic and Duplex stainless steel present under the Insulation will accelerate the corrosion. The chloride salts are from the insulation materials itself. Worse is the present of Hot elevated water temperature under the CUI.

• Water trapped under the Insulation materials (Rockwool, Glass Wool, Perlite, Calcium Silicate) with other variables under the CUI will accelerate the corrosion.

WAY FORWARD TO MITIGATE CUI

1. Sherwin Williams : Hi Temp 1200 CUI Coating (Passes Boiling Water Test - critical for CUI)
2. Sherwin Williams : HeatFlex 3500 - Insulation Coating
3. Aerogel Blanket : Hydrophobic insulation Blanket (Advance Insulation Material)
4. NDT Inspection without opening the Cladding