Overview
ISO 7963:2022 - Non‑destructive testing - Ultrasonic testing - Specification for calibration block No. 2 defines the manufacturing, dimensional, material and usage requirements for a compact steel calibration block used to set and check ultrasonic test equipment. The third edition updates structure and normative references and aligns manufacturing/tempering steps with ISO 2400.
Key topics and technical requirements
- Material: Blocks shall be made from steel grade S355J0 or equivalent (see EN 10025-2).
- Manufacture & heat treatment: Recommended semi‑finished block size (e.g. 320 × 120 × 30 mm) with defined heat treatment sequence (austenitizing, quenching, tempering) and removal of at least 2 mm after heat treatment.
- Ultrasonic properties: Longitudinal and transverse wave velocities must be determined (vL = 5 920 ± 30 m/s; vT = 3 255 ± 15 m/s) with a maximum permissible error of ±0.2 %.
- Inspection for internal discontinuities: Ultrasonic inspection using a ≥10 MHz longitudinal probe (10–15 mm transducer size) after heat treatment; no echo from imperfections may exceed grain scatter noise (set to 10 % full screen height).
- Dimensions & surface finish: Exact block geometry and scales are specified (see Figure 1); surface roughness (Ra) values follow ISO 21920‑2. Engraved marks depth and tolerances (e.g. 0.1 ± 0.05 mm depth) are specified.
- Permanent marking: Manufacturer identification, reference to ISO 7963, and unique serial number must be engraved.
- Methods of use: Procedures for setting the time base (straight‑beam and miniature angle‑beam probes up to 125 mm), sensitivity setting and probe checking (use of back‑wall echo, 5 mm through‑hole, cylindrical radii), determination of probe index point and beam angle are provided.
Applications and users
ISO 7963:2022 is intended for NDT practitioners and organizations that require reliable ultrasonic testing calibration tools, including:
- NDT technicians and inspection engineers
- Calibration and testing laboratories
- Manufacturers of ultrasonic probes and instruments
- Welding inspectors and quality managers in industries using ultrasonic inspection (e.g., oil & gas, power generation, transportation, fabrication)
The standard enables routine checks of instrument time base, sensitivity, beam angle and probe index point using a compact, portable calibration block.
Related standards
- ISO 2400 - Specification for calibration block No. 1 (larger block; referenced for velocity determination and manufacturing guidance)
- ISO 5577 - NDT - Ultrasonic testing vocabulary
- EN 10025‑2 - Technical delivery conditions for S355J0 steel
Using ISO 7963:2022 ensures consistent NDT calibration practice, traceable block manufacture, and repeatable ultrasonic settings for accurate defect detection and instrument verification.