S-Scan (Sectorial Scan)

An S-scan is a phased-array ultrasonic image showing a fan of beams swept through a range of angles from a single probe position, displaying defect indications across the angular range in a single view.

Definition

The S-scan, or sectorial scan, is the signature display of PAUT. By electronically steering the beam from a low to a high angle (for example 40° to 70°), the system builds an angular slice through the inspection volume, displayed as color-coded amplitude over a fan-shaped sector.

Technical Context

S-scans accelerate weld inspection because every weld zone is interrogated from many angles in one probe stop. The display shows depth and angular position of any reflector.

Related terms

Phased Array Ultrasonic Testing (PAUT) — PAUT is an advanced ultrasonic technique using a multi-element transducer (16–256 elements) with electronic beam steering and focusing, producing sectorial, linear, and compound scans for superior weld inspection and defect characterization.
L-Scan (Linear Scan) — An L-scan is a phased-array ultrasonic image produced by electronically stepping a fixed-angle beam along the array aperture, generating a side-by-side series of A-scans at constant angle and varying position.
A-Scan — An A-scan is the basic ultrasonic display showing signal amplitude (vertical axis) versus time-of-flight (horizontal axis) from a single transducer position, used to identify, size, and locate reflectors.

More data terms

B-Scan · C-Scan · D-Scan · Distance-Amplitude Correction · Distance-Gain-Size · Time-Corrected Gain · Gating · Decibel · Indication · False Indication

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.