API 570 Piping Inspection Code

API 570 is the inspection, repair, alteration, and rerating code for in-service piping systems in refineries and chemical plants, defining inspection intervals based on piping class and corrosion rate, and requiring API 570 inspector certification.

Definition

API 570 classifies piping into Class 1 (highest risk), Class 2, Class 3, and Class 4. Inspection intervals (external 5 yr, thickness 10 yr or half remaining life) and CML (Condition Monitoring Locations) are required.

What this document is

The API inspection code for in-service piping systems, covering inspection intervals, thickness monitoring, corrosion rate and remaining life calculation, repair and alteration, and re-rating.

How it is applied

Its logic is condition monitoring locations, measured thickness over time, corrosion rate, and an interval derived from remaining life — with the inspector authorised to make judgements the code defines. Piping is classified by service so that effort follows consequence.

The common misuse

Computing corrosion rate from two readings taken at nominally the same location by different technicians with different instruments. Measurement scatter can exceed real loss, and the resulting rate — and interval — is then noise.

Where API 570 Piping Inspection Code fits in an inspection programme

A term is only useful when it connects to a decision. API 570 Piping Inspection Code appears in written procedures, in technique sheets, and in the records an owner or accreditation body reviews afterwards — which means the way it is defined in your documentation has to match the way it is applied on site. Where the two drift apart, audits find it. Atlantis writes and reviews procedures against the governing codes, trains inspection personnel to apply them, and builds the record-keeping that makes the evidence retrievable years later. Procedure development and code consulting · NDT training and certification · Ask us about your programme.

Related terms

API 510 Pressure Vessel Inspection Code — API 510 is the inspection, repair, alteration, and rerating code for in-service pressure vessels in refineries and chemical plants, requiring periodic external and internal inspection by certified API 510 inspectors.
API 653 Tank Inspection, Repair, Alteration, and Reconstruction — API 653 is the inspection, repair, alteration, and reconstruction code for above-ground welded steel storage tanks built to API 650, defining periodic external (5 yr), ultrasonic (10 yr), and internal (typically 10 yr) inspection intervals.
ASME B31.3 Process Piping — ASME B31.3 is the process piping code covering chemical plants, petroleum refineries, and similar process facilities, defining fluid service categories (Category D, Normal Fluid Service, Category M, High Pressure, Elevated Temperature) each with specific NDT r
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.

More standard terms

ASME Section V · ASME Section VIII · ASME Section IX · ASME Section XI · ASME B31.1 Power Piping · ASME B31.8 Gas Transmission and Distribution Piping · ASME B31.4 Liquid Pipelines · API 571 Damage Mechanisms · API 579-1 / ASME FFS-1 Fitness-for-Service · API 581 Risk-Based Inspection Methodology

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.