Get Simulation On Corrosion Under Insulation Form

Wrapping equipment with aluminum foil before applying insulation will reduce the risk of corrosion, since the foil provides a physical barrier that prevents the saturated chloride solution from reaching the metal surface.

The most common and straightforward way to inspect for corrosion under insulation is to cut plugs in the insulation that can be removed to allow for ultrasonic testing. The other commonly used methods are radiography, and complete insulation removal.

What causes corrosion under insulation? Corrosion under insulation, or CUI, occurs when moisture enters through holes or cracks in the insulation and becomes trapped against the hot pipe. Prolonged moisture exposure can cause rapid rusting and corrosion on the pipe's surface.

Corrosion under insulation (CUI) is typically caused when insulation gets wet due to water ingress beneath the weather barrier (jacketing), or moisture condensation from steam tracing leaks, cooling tower drift or ambient air in humid and windy climates.

Moisture ingress into conventional insulation materials usually results in the acceleration of corrosion upon the underlying surface, consequently structural failure of pipework and other insulated equipment will occur and can have catastrophic outcomes.

Corrosion may attack the jacketing, the insulation hardware, or the underlying equipment. For high temperature equipment, water entering an insulation material and diffusing inward will eventually reach a region of dryout at the hot pipe or equipment wall.

In the simplest terms, corrosion under insulation (CUI) is any type of corrosion that occurs due to a moisture build-up on the external surface of insulated equipment. The build-up can be caused by a multitude of factors, with corrosion most commonly found to be galvanic, chloride, acidic, or alkaline corrosion.

A what temperature does CUI occur? CUI is generally, but not exclusively, a high risk in the temperature range of -4°C – +175°C (25°F to 347°F). However, the highest corrosion rates are more commonly experienced in operational conditions between 60°C – 120°C (140°F to 248°F).