EN ISO 17640:2018 PDF

Overview

EN ISO 17640:2018 - "Non‑destructive testing of welds - Ultrasonic testing - Techniques, testing levels, and assessment" provides standardized procedures for manual ultrasonic testing (UT) of fusion‑welded joints in metallic materials. The standard applies to welds of thickness ≥ 8 mm with low ultrasonic attenuation at object temperatures of 0 °C to 60 °C, and is primarily intended for full‑penetration, ferritic welded joints. Where material‑dependent ultrasonic values are required, the standard references longitudinal and transverse wave sound velocities of (5 920 ± 50) m/s and (3 255 ± 30) m/s respectively.

Key Topics

• Scope and applicability
  • Manual UT of fusion welds in low‑attenuation metallic materials, mainly ferritic steels.
• Testing levels
  • Four testing levels (A, B, C, D) corresponding to different probabilities of detection.
  • Guidance for selecting levels A, B and C provided in Annex A.
  • Level D reserved for special applications (e.g., non‑ferritic metals, partial‑penetration welds, automated testing, or temperatures outside 0–60 °C) and is used only when specified.
• Assessment techniques
  • Two accepted assessment approaches:
    • Evaluation based primarily on discontinuity length and echo amplitude.
    • Characterization and sizing by probe movement (probe‑based sizing techniques).
• Technical requirements
  • Personnel qualifications and certification requirements for NDT operators.
  • Test equipment and probe parameters: frequency, angles of incidence, transducer size, adaptation to curved surfaces, and coupling media.
  • Procedures for range and sensitivity setting, transfer correction, and signal‑to‑noise considerations.
  • Test volume definition, surface preparation, parent metal testing, scanning paths, location and sizing conventions, and test reporting.

Applications

• Routine and acceptance testing of welded joints in structural and pressure‑bearing ferritic steel components (pipes, vessels, bridges, heavy fabrication) where weld thickness ≥ 8 mm.
• Quality control in fabrication, in‑service inspection planning, repair verification, and acceptance testing to specified detection probabilities.
• Users: NDT engineers, welding inspectors, quality managers, fabricators, certification bodies and clients specifying acceptance criteria.

Related Standards

Key normative references cited by EN ISO 17640:2018:

• ISO 5577 - UT vocabulary
• ISO 9712 - Qualification and certification of NDT personnel
• ISO 11666 - Acceptance levels for UT of welds
• ISO 16810 - UT general principles
• ISO 16811 - UT sensitivity and range setting
• ISO 16826 - UT examination for discontinuities perpendicular to the surface

This standard is essential when specifying ultrasonic weld testing procedures, selecting testing levels, or interpreting UT results for ferritic welded joints. Keywords: EN ISO 17640:2018, ultrasonic testing, welds, NDT, testing levels, ferritic steel, probability of detection.