Notch Reference
A notch reference is a machined surface-breaking notch of known depth, length, and width used to calibrate ultrasonic systems for surface-crack detection and to set acceptance thresholds for shear-wave inspection.
Definition
Notches are typically EDM-cut surface-breaking slots used as reference reflectors for surface or angled-beam inspection. They simulate planar cracks and are widely used in pipeline AUT and aerospace inspection calibration.
Related terms
- Calibration Block — A calibration block is a reference specimen with known geometry and reference reflectors (side-drilled holes, flat-bottom holes, notches) used to set ultrasonic instrument sensitivity, range, and angle prior to inspection.
- Reference Reflector — A reference reflector is a machined feature in a calibration block — typically a side-drilled hole, flat-bottom hole, or notch — used as a known target to set instrument gain and build sizing curves.
- Shear Wave — A shear wave is an ultrasonic mode in which particle motion is perpendicular to the direction of propagation; in steel, shear waves travel at ~3,250 m/s and are produced by mode conversion at angled wedges for weld inspection.
More equipment terms
Transducer · Dual-Element Probe · Angle-Beam Probe · Normal-Beam Probe · Couplant · Side-Drilled Hole · Flat-Bottom Hole · X-Ray Tube · Gamma Source · Iridium-192
Where this comes up in practice
Terms like this one appear in three places that matter commercially: the written practice that governs how your personnel are qualified, the procedures and technique sheets that define how an examination is actually performed, and the evidence an auditor or client asks for when they want to know why an inspection was accepted. Getting the terminology right is the easy part; being able to produce the qualification record, the calibration traceability and the procedure revision that applied on the day of the inspection is the part that decides audits.
Atlantis NDT provides NDT training and certification against ASNT SNT-TC-1A and ISO 9712, ASNT Level III consulting for written practices and procedure approval, inspection management software that holds qualification, calibration and procedure-revision evidence in recoverable form, and an asset integrity platform that binds inspection results to the asset they describe. Browse the full NDT glossary or ask a Level III directly.