API 571 Damage Mechanisms
API 571 is the recommended practice describing damage mechanisms affecting refining and petrochemical equipment, including general/uniform corrosion, localized corrosion, environmentally assisted cracking, metallurgical degradation, mechanical damage, and high-temperature damage.
Definition
API 571 is the foundational document for understanding in-service degradation. It catalogs over 60 damage mechanisms, each with description, affected materials, critical factors, detection methods, and prevention strategies. RBI programs reference API 571 to identify likely degradation paths.
Related terms
- Risk-Based Inspection (RBI) — Risk-based inspection is an inspection strategy in which equipment inspection scope, methods, and intervals are prioritized based on combined probability of failure and consequence of failure, optimizing inspection investment per the API 580/581 framework.
- API 580 Risk-Based Inspection — API 580 is the recommended practice defining the elements, framework, and management responsibilities for a Risk-Based Inspection (RBI) program, in which inspection intervals and methods are prioritized by combined probability and consequence of failure.
- API 581 Risk-Based Inspection Methodology — API 581 is the recommended practice that provides the quantitative methodology — probability of failure and consequence of failure calculations — for a Risk-Based Inspection program implemented under API 580.
- Corrosion Under Insulation (CUI) — Corrosion under insulation is external corrosion of carbon and low-alloy steel piping and vessels hidden beneath thermal insulation, caused by water ingress that accelerates corrosion in the 60–175 °C temperature range.
Further reading
api 571 damage mechanisms complete industry guide
More standard terms
ASME Section V · ASME Section VIII · ASME Section IX · ASME Section XI · ASME B31.1 Power Piping · ASME B31.3 Process Piping · ASME B31.8 Gas Transmission and Distribution Piping · ASME B31.4 Liquid Pipelines · API 510 Pressure Vessel Inspection Code · API 570 Piping Inspection Code
Where this comes up in practice
Terms like this one appear in three places that matter commercially: the written practice that governs how your personnel are qualified, the procedures and technique sheets that define how an examination is actually performed, and the evidence an auditor or client asks for when they want to know why an inspection was accepted. Getting the terminology right is the easy part; being able to produce the qualification record, the calibration traceability and the procedure revision that applied on the day of the inspection is the part that decides audits.
Atlantis NDT provides NDT training and certification against ASNT SNT-TC-1A and ISO 9712, ASNT Level III consulting for written practices and procedure approval, inspection management software that holds qualification, calibration and procedure-revision evidence in recoverable form, and an asset integrity platform that binds inspection results to the asset they describe. Browse the full NDT glossary or ask a Level III directly.