ISO 23279-2017 PDF

Full title and description

Non‑destructive testing of welds — Ultrasonic testing — Characterization of discontinuities in welds (ISO 23279:2017). This International Standard defines a systematic procedure to characterise ultrasonic indications in welded joints by classifying them as originating from planar or non‑planar discontinuities and gives guidance for consistent interpretation of UT signals from embedded and surface‑breaking defects (including those that become surface‑breaking after removal of weld reinforcement).

Abstract

ISO 23279:2017 specifies a decision‑chart based method and supporting guidance to classify ultrasonic indications found in welds. The standard combines multiple parameters — geometrical position and welding technique, maximum echo amplitude, directional reflectivity, static A‑scan echo pattern and dynamic (envelope) echo behaviour — in a staged procedure to decide whether an indication is likely planar (for example crack‑like) or non‑planar (for example volumetric inclusions or clusters). Annexes provide a flowchart and informative guidance on directional reflectivity and echo pattern interpretation.

General information

• Status: Published (current edition).
• Publication date: 10 August 2017.
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 25.160.40 (Welded joints and welds).
• Edition / version: Edition 3 (2017).
• Number of pages: 14.

Scope

This standard applies to the ultrasonic characterisation of indications (discontinuities) in fusion‑welded joints and similar weld types. It is intended for indications located within the weld or close to the weld surface, including those that become surface‑breaking after removal of reinforcement. ISO 23279:2017 provides a procedure to help distinguish planar discontinuities (cracks, lack of fusion/planar defects) from non‑planar discontinuities (inclusions, porosity, clusters) to support subsequent acceptance, repair or further examination decisions. It is not a complete acceptance standard by itself but complements UT technique and acceptance standards.

Key topics and requirements

• Flowchart (staged decision procedure) for classification of indications into planar or non‑planar types.
• Five‑stage assessment approach using combined parameters (amplitude thresholds, position, directional reflectivity, static A‑scan pattern and dynamic/envelope behaviour).
• Guidance on directional reflectivity comparisons (multiple probe angles and amplitude imbalance criteria) to detect elongated planar reflectors.
• Reference comparisons for A‑scan patterns (practical examples and reference responses) to separate point‑like and planar echoes.
• Probe and waveform advice (use of compatible probe frequencies/types for detection and classification, consideration of wavelength and mode conversions).
• Recommendations for additional examination (extra UT angles/scans, repeated scans, phased array/TOFD or radiography) where classification is ambiguous.
• Informative annexes with flowchart, examples and guidance on interpreting echo patterns and directional behaviour.

Typical use and users

Primary users are NDT technicians and weld inspectors performing manual or semi‑automated ultrasonic examinations, NDT supervisors and engineers responsible for weld inspection procedures, quality managers in fabrication and power generation, inspection bodies and welding code authors. The standard is used to standardize interpretation of UT indications, to support sizing and acceptance decisions (in conjunction with acceptance standards), and to inform when complementary NDT or weld repair is required.

Related standards

Standards commonly used together with ISO 23279:2017 include ISO 17640 (UT techniques, testing levels and assessment), ISO 11666 (UT acceptance levels for welds), ISO 10863 (TOFD), ISO 13588 (automated phased array UT), ISO 5817 (weld quality levels), ISO 17635 (general rules for NDT of welds) and ISO 9712 (qualification and certification of NDT personnel). Earlier editions of ISO 23279 (for example the 2010 edition) have been superseded by the 2017 edition.

Keywords

ultrasonic testing, weld inspection, discontinuity characterization, planar discontinuity, non‑planar discontinuity, A‑scan, directional reflectivity, echo pattern, NDT, weld defects

FAQ

Q: What is this standard?

A: ISO 23279:2017 is an international standard that specifies a procedure to characterise ultrasonic indications in welds by classifying them as originating from planar or non‑planar discontinuities.

Q: What does it cover?

A: It covers a staged, flowchart‑based method using amplitude, position, directional reflectivity, static A‑scan pattern and dynamic (envelope) behaviour to help distinguish crack‑like (planar) from volumetric or cluster (non‑planar) discontinuities in welded joints. It includes informative guidance and examples but is not an acceptance standard by itself.

Q: Who typically uses it?

A: NDT technicians, welding inspectors, NDT supervisors, inspection bodies, quality managers and engineers who perform or supervise ultrasonic examinations of welds and who need a standardized method to interpret UT indications.

Q: Is it current or superseded?

A: The 2017 edition is the current third edition of ISO 23279. Earlier editions (for example 2010) have been superseded by the 2017 publication.

Q: Is it part of a series?

A: Yes. ISO 23279:2017 is part of the family of ISO standards for non‑destructive testing of welds (UT standards) and is typically used alongside standards such as ISO 17640, ISO 11666, ISO 10863 and ISO 13588, which address UT techniques, acceptance levels and specialised UT methods.

Q: What are the key keywords?

A: Ultrasonic testing; welds; discontinuities; planar; non‑planar; A‑scan; directional reflectivity; echo envelope; NDT; weld inspection.