UT · Conventional NDT
Ultrasonic Testing
The Method
How UT works.
UT introduces high-frequency sound into the material through a transducer and couplant. Sound reflects from the back wall, geometric features, and discontinuities; the inspector uses the amplitude and position of returning signals to locate and evaluate reflectors.
Straight-beam techniques are used for thickness measurement and lamination scanning. Angle-beam (shear wave) techniques direct sound into welds at a refracted angle, with sensitivity set on calibrated reference standards. Where imaging, multiple angles, or recorded data are needed, phased array UT extends the method.
Applications
Where UT is used
- Full- and partial-penetration weld examination
- Plate lamination scanning before welding
- Wall-thickness and corrosion measurement
- Forgings and heavy-section components
Detection capability
What UT can detect
- Cracks and other planar discontinuities
- Incomplete fusion and incomplete penetration
- Slag inclusions
- Laminations in plate
- Wall loss from corrosion or erosion
Methods & Equipment
Typical equipment
- Digital ultrasonic flaw detectors
- Straight-beam, angle-beam, and dual-element transducers
- Thickness gauges
- Calibration blocks and reference standards
Technical Considerations
Limits and requirements to plan for.
Orientation
Response depends on the angle between the beam and the reflector, so scan plans use multiple angles and directions.
Calibration
Instruments are calibrated on the reference blocks the procedure specifies, with sensitivity checks during the examination.
Material and geometry
Coarse-grained austenitic welds, thin sections, and rough surfaces can limit effectiveness.
Technician skill
Manual UT depends on scanning technique and interpretation, which is why qualification matters.
In Practice
UT in industry.
Shipbuilding
Volumetric weld examination where specified.
Power & process plants
Thickness surveys and weld examination during construction and outages.
Heavy manufacturing
Lamination checks and thick-section welds.
Industries that benefit
How TCI Supports You
What you get from TCI.
- UT technicians for straight-beam and shear-wave examination
- Technique sheets reviewed by Level III personnel
- PAUT available when the job calls for imaging or encoded data
Let's discuss your inspection requirements.
Tell us about your project, schedule, and the specifications you work to. A member of our leadership team will respond directly.