Ultrasonic wheel units may be used for which examination types (alternative wording)?

• A. Angle beam or shear wave examinations
• B. All of the above
• C. Straight or longitudinal examinations
• D. Surface wave or Rayleigh wave examinations

Answer: (B)

Ultrasonic wheel units are versatile transducers designed to inspect curved surfaces by rolling along the area being examined, and they can be configured to deliver different wave modes and beam directions. By selecting the appropriate wedge and orientation, you can create angle-beam paths and generate shear waves for inspecting around corners or welds. If you set it up for a straight-beam approach, you can obtain longitudinal (normal) incidence along the component’s length, useful for detecting flaws parallel to the surface. With suitable coupling and setup, wheel units can also excite surface waves (Rayleigh waves) to probe the surface region for defects. This flexibility means wheel units can handle angle-beam, straight-beam, and surface-wave examinations, so all of the above is the best choice.