Published on 19-Feb-2024

Best Inspection Methods for Corroion Under Insulation

Best Inspection Methods for Corroion Under Insulation

Sources - Inspectioneering

Table of Content


The difficulties and expense of looking for and preventing the very common, but elusive problem of corrosion under insulation (CUI) are widely known and well-documented.

CUI is hard to find because it’s hidden under the insulation and there are substantial costs and logistical issues involved in removing the coverings, inspecting the piping, and then reinstating them. 

Even cutting plugs in the covering and NDT Testing those is a time-consuming and labor-intensive process, plus there may be further complications if asbestos is identified and needs to be removed safely.

Numerous non-destructive testing methods are used to inspect for Corrosion Under Insulation (CUI) which is often only detected when it is fairly advanced and there is visible leakage of fluid. 

Naturally, industries prefer NDE Technologies that enable inspection without necessitating the removal of the insulation coverings, and as a rule, the various NDT Testing Methods aren’t used on their own but are combined to complement one another and achieve the best outcome.

Corrosion Under Insulation (CUI)

Inspection Methods for Corrosion Under Insulation (CUI)

Here are the Best Inspection Methods for CUI

1. Visual Inspection

Visual Inspection is the simplest and most obvious NDT Method, which involves removing the covering (either partially or wholly), visually examining the surface for any signs of corrosion or damage, and then replacing the insulation. 

It is effective but the downside is that it is expensive, and engineers are only able to inspect the outer areas of the Piping for defects and not the internal space. 

Insulation may also need to be replaced, adding to the overall cost. The NDT Process also needs to be done carefully and properly otherwise the integrity of the structure may be compromised with the additional risk of contamination.