Piping corrosion circuit or Corrosion loop / Piping Circuitization and Corrosion Modelling, is carried out as part of either a Risk Based Inspection analysis (RBI) or Materials Operating Envelope analysis (MOE).
It is the systematization of the piping components versus failure modes analysis into materials operating envelope.
Corrosion Circuits are utilized in the Integrity Management Plan (IMP) which forms a part of the overall Asset integrity management system and is an integral part of any RBI analysis.
Many times a "system" will be a broad overview of the facilities process flow, broken by stream constituents, while a circuit level analysis breaks systems into smaller "circuits" that group common metallurgies, equal (or roughly equal) temperatures and pressures, and expected damage mechanisms.
It is carried out in order to: Typically, this is performed at the outset of any Mechanical Integrity program i.e. as the facility is built, modified and operated throughout its life.