A facility EPR inspected had a location with an environment that was hot, humid, salt laden, and highly polluted. This reality was addressed as such in the EPC contract with strict coatings requirements.
In the process of performing coating inspections it was discovered that most, perhaps all, of the supports in one portion of the facility were fabricated from pipe but had open ends and are under severe corrosive attack.
As a comparison, a similar design was used for base supports of related equipment, but with the ends capped. So, while it is assumed there are no internal coatings, corrosion would eventually occur and then be arrested and not progress.
In the attached photos the problem can be observed. While identification of the issue is relatively easy, fixing this problem took special technical consideration and analysis by the involved parties. The difficulty was obtaining a proper surface preparation inside the pipe and then properly applying a coating. Another option was to cap the ends after dealing with some surface preparation to remove excess contamination thereby assuming the situation would progress like a closed end pipe support.
According to ISO 12944-2, Annex B, 1.2 (corrosion in box members and hollow components) specifies these assemblies (supports) should have been airtight by means of welding. Since they were not, and considered accessible, proper coating processes and materials should have been used prior to installation.
This is an example of a problem that was easy to resolve during fabrication, but quite difficult and time consuming once field installation was completed. There were many hundreds of these supports and they seemed to be in locations that were difficult to access.
This situation was quite different from many of the blog posts because it was not originating as a field issue. The origins of this problem was a simple oversight in engineering or fabrication.
Little to none.
In Situ repair costs were comparatively high.