Equipment Sales · Solution
Fighting Corrosion Under Insulation
On insulated pipes, tanks and process equipment, corrosion often starts where nobody can see it: under the insulation. Fighting CUI means keeping moisture out, removing any water that gets in and keeping access for inspection.
What is CUI and why does it occur?
Corrosion under the insulation
CUI (corrosion under insulation) forms beneath the insulation of pipes, tanks, pressure vessels and process equipment; it is an integrity risk that grows as equipment ages.
Moisture is the main driver
Corrosion is started not by the insulation itself but by oxygenated water in contact with the metal surface; wet insulation touching the surface increases the risk.
Where water enters and collects
Clamps and nozzles penetrating the cladding, insulation terminations, flange connections and horizontal transitions such as tank chimes are among the highest-risk areas.
Prevention approach
Keep moisture out
Sealing elements such as clamp covers, termination seals and pipe seals stop water from entering the insulation.
Remove water that gets in
Drainage at the lowest points of the insulation, combined with an air gap and ventilation, helps the insulation dry out.
Keep insulation off the surface
Spacers hold the insulation away from the pipe surface; non-contact designs stop wet insulation from touching the metal.
Inspection and monitoring
Inspection ports allow thickness measurement and visual inspection without removing large sections of insulation; fitting and closing the ports correctly reduces the risk of water ingress. Water indicators help monitor moisture under the insulation.
Final product selection and interpretation of standards for a specific application must be confirmed by qualified technical staff.
CUI mitigation products
Browse Integrity Products spacers, sealing elements, inspection ports and insulation systems in the catalogue and add them to your quote list.
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