Materials Engineering, Evaluation, and Inspection

Ultrasonic Testing

Spectrum uses Ultrasonic Testing (UT) methods, including resonance and pulse-echo, to detect surface and marginally subsurface flaws in a variety of materials. Typical inspections involved welds, tubing, joints, valves, castings, billets, forgings, shafts, structural components and pressure vessels. Spectrum is able to determine thickness and mechanical properties while monitoring service wear and deterioration due to corrosion or erosion without removal or disassembly of the component.

UT gauges material thickness based on the time required for sound emitted from the transducer to travel through the component and back to the transducer. UT inspections can be performed on both metallic and non-metallic surfaces, such as wood and concrete, depending on the acoustic properties of the material.


  • Metals, non-metals and composites
  • Surface and slightly subsurface flaws can be detected
  • Can be applied to welds, tubing, joints, castings, billets, forgings, shafts, structural components
  • Used to determine thickness and mechanical properties
  • Monitoring service wear and deterioration


  • Usually contacting, either direct or with intervening medium required (e.g. immersion testing)
  • Special probes are required for applications
  • Sensitivity limited by frequency used and some materials cause significant scattering
  • Scattering by test material structure can cause false indications
  • Not easily applied to very thin materials


  • Good penetrating power, allowing for detection of faults deep in the material
  • High sensitivity, allowing for detection of very small flaws
  • Requires accessibility from just one surface
  • Can be more accurate than other nondestructive techniques
  • No effect on nearby personnel, operations, equipment or materials
  • Instruments are highly portable


  • Requires experienced technicians
  • Requires significant technical knowledge