Why might a technician use a wedge during Ultrasonic Testing?

A technician uses a wedge during Ultrasonic Testing primarily to convert longitudinal waves into shear waves. This conversion is important for inspecting certain materials or geometries where shear wave propagation may be more effective in detecting flaws or discontinuities. The wedge is typically made from a material that allows for the proper transmission of sound waves at an angle, facilitating this conversion.

In Ultrasonic Testing, longitudinal waves travel straight through a medium, while shear waves can provide better sensitivity to specific types of flaws, such as cracks that are oriented perpendicular to the wave path. By using a wedge, the technician can optimize the testing method for the given material and detect defects that might otherwise go unnoticed if only longitudinal waves are used.

Other options, such as enhancing sound wave amplitude and reducing equipment weight, are not primary functions of a wedge in Ultrasonic Testing. Additionally, calibration of the transducer typically involves using specific calibration blocks or standards rather than a wedge. Therefore, the use of a wedge in Ultrasonic Testing is crucial for converting wave types to maximize the efficiency and effectiveness of flaw detection.