To evaluate and accurately locate discontinuities after scanning a part with a paintbrush transducer, it is generally necessary to use a:

To evaluate and accurately locate discontinuities after scanning a part with a paintbrush transducer, it is generally necessary to use a:

• A. Scrubber
• B. Search unit with a smaller crystal
• C. Grid map
• D. Crystal collimator

Answer: (B)

Broad-area scanning with a paintbrush transducer covers a wide area but sacrifices the precision needed to pinpoint a flaw. To accurately locate discontinuities, you generally need a search unit with a smaller crystal because the smaller crystal sharpens the ultrasonic beam, giving better lateral and depth resolution. That tighter beam footprint lets you determine the exact position of a flaw relative to the surface, improving accuracy in locating its location, size, and orientation. A scrubber isn’t an instrument that improves localization, so it doesn’t address the measurement precision. A grid map helps record and correlate data with positions, but it doesn’t by itself enhance the resolution needed to pinpoint a flaw. A crystal collimator isn’t typically used in this UT context and won’t provide the necessary improvement in spatial resolution.

Broad-area scanning with a paintbrush transducer covers a wide area but sacrifices the precision needed to pinpoint a flaw. To accurately locate discontinuities, you generally need a search unit with a smaller crystal because the smaller crystal sharpens the ultrasonic beam, giving better lateral and depth resolution. That tighter beam footprint lets you determine the exact position of a flaw relative to the surface, improving accuracy in locating its location, size, and orientation.

A scrubber isn’t an instrument that improves localization, so it doesn’t address the measurement precision. A grid map helps record and correlate data with positions, but it doesn’t by itself enhance the resolution needed to pinpoint a flaw. A crystal collimator isn’t typically used in this UT context and won’t provide the necessary improvement in spatial resolution.