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. It groups piping materials / chemical make-up into systems / sub systems and assigns corrosion mechanisms. These are then monitored over the operating lifetime of the facility. This analysis is performed on circuit inspection results to determine and optimize circuit corrosion rates and measured thickness/dates for circuit components. 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.