Jim McVay, MISTRAS Group, USA, explains how corrosion studies can be used to determine potential damage mechanisms, corrosion types, and corrosion rate/potential to inform risk assessment and inspection planning.
C
orrosion studies – also known as degradation mechanism reviews (DMRs) – examine the process, design, materials, and history of a process unit. They are now relatively common exercises in operating facilities, necessary for the sufficiently well-grounded and dynamic inspection programmes needed in today’s operating environments. API RP 970 (Corrosion Control Documents) helps, but it has omissions in areas that responsible operators need to address. Standardised criteria for consistent determinations of environmental cracking mechanism vulnerabilities is but one example; rigour of data review and analyses is another. The execution of a corrosion study is complex. It requires a multi-disciplined team of inspection and engineering subject HYDROCARBON 33
ENGINEERING
July 2021
