Overview
EN ISO 7963:2022 - Non-destructive testing - Ultrasonic testing - Specification for calibration block No. 2 defines the requirements for a compact steel calibration block used to set and check ultrasonic test equipment. Published by CEN/ISO, this standard specifies dimensions, material, manufacture and methods of use for calibration block No. 2 (sometimes called the Rompas block or miniature angle‑beam block, MAB). It is intended for routine field checks of ultrasonic instruments rather than full, laboratory-level calibration.
Key topics and technical requirements
- Material: Blocks shall be manufactured from steel grade S355J0 or an equivalent grade (referenced EN 10025-2).
- Dimensions and tolerances: Exact dimensions are specified (see figure in the standard); general machining tolerances such as ±0.10 mm are applied and surface roughness values (Ra) are given according to ISO 21920-2.
- Manufacture and heat treatment:
- Semi-finished block rough‑machined to ~320 × 120 × 30 mm before heat treatment.
- Heat treatment sequence (as specified): austenitizing at 920 °C for 30 min, water quench, tempering at 650 °C for 3 h, then air‑cooling.
- After heat treatment, at least 2 mm is removed from all surfaces; internal soundness must be verified ultrasonically.
- Acoustic properties:
- Longitudinal wave velocity vL: (5920 ± 30) m/s
- Transverse wave velocity vT: (3255 ± 15) m/s
- Verification of velocities and homogeneity is required (precision and permissible errors defined).
- Methods of use:
- Procedures for time base setting (straight‑beam and miniature angle‑beam probes), sensitivity setting, and probe checking (including beam angle and probe index point for miniature angle‑beam probes).
- Conformity and documentation: Clause for declaration of conformity and normative references (ISO 2400, ISO 5577, EN 10025-2).
Applications and who uses it
- Routine verification and quick checks of ultrasonic flaw detectors and probes in field or workshop environments.
- Used by:
- NDT technicians and inspectors conducting weld inspections and welded‑joint testing.
- Calibration laboratories needing a compact check block for daily or on-site verification.
- Manufacturers of ultrasonic probes and equipment for functional checks.
- Welding quality assurance teams and third‑party inspection bodies.
- Practical value: enables rapid time-base and sensitivity checks, spot verification of beam angle and probe index point, and portable confirmation that ultrasonic equipment performs within expected parameters.
Related standards (brief)
- ISO 2400 - Calibration block No. 1 (larger, fuller laboratory checks)
- ISO 5577 - Ultrasonic testing vocabulary
- EN 10025-2 - Technical delivery conditions for S355J0 steel
Keywords: EN ISO 7963:2022, calibration block No. 2, ultrasonic testing, non‑destructive testing, NDT, S355J0, time base, sensitivity, miniature angle‑beam probe, ISO 2400.