Overview
EN ISO 22825:2017 (CEN adoption of ISO 22825:2017) provides guidance on developing ultrasonic testing procedures for welds in austenitic steels, duplex steels, nickel‑based alloys and dissimilar metal welds. It addresses the particular challenges of ultrasonic non‑destructive testing (NDT) on coarse‑grained, anisotropic weld metals where beam distortion, unexpected reflections and mode conversion can impede conventional inspection. The document covers both manual and mechanized ultrasonic testing, and includes provisions for phased‑array techniques.
Key topics and technical requirements
- Scope and purpose: Defines the approach for procedure development for manufacturing quality assessment and detection of service‑induced discontinuities. Acceptance levels are not included but can be applied according to the testing scope.
- Information before testing: Lists required data to define the inspection specification and operator needs.
- Personnel and equipment: Requirements for qualified personnel and suitable test equipment - includes conventional ultrasonic systems and phased‑array equipment (phased array is explicitly included in the 2017 edition).
- Wave selection and range setting: Guidance on compression (longitudinal) wave angle‑beam techniques, refracted compression and creeping wave use where shear‑wave techniques are ineffective.
- Sensitivity setting: Procedures for sensitivity calibration, including the use of side‑drilled holes and other reference reflectors; annexes provide calibration block examples for stainless steels and reference block guidance.
- Procedure development and content: How to select and optimize ultrasonic techniques, prepare representative reference weld blocks, and validate effectiveness before finalizing procedures.
- Evaluation and reporting: Classification and sizing of indications, practical scanning guidance, and the required content of test reports.
Practical applications
- Routine and acceptance weld inspection in petrochemical, power generation, nuclear, and aerospace sectors where austenitic and nickel alloys are used.
- In‑service inspections for stress‑corrosion cracking, intergranular defects and other discontinuities in critical welded components.
- Development of site‑specific NDT procedures and qualification of ultrasonic inspection methods for fabrication and maintenance.
Who uses this standard
- NDT engineers and inspectors, welding engineers, inspection authorities, quality managers and organizations developing ultrasonic weld inspection procedures for challenging materials.
Related standards
- ISO 5577 (Ultrasonic testing - Vocabulary)
- ISO 7963 (Ultrasonic testing)
(EN ISO 22825 references these and other normative documents for vocabulary, calibration and technique details.)
Keywords: ultrasonic testing, EN ISO 22825, austenitic steels, nickel‑based alloys, non‑destructive testing, weld inspection, phased array, NDT procedure.
