Liquid Penetrant Testing Level 2 (PT-2) Practice Exam

For parts with keyways and threads, which penetrant process is most suitable?

1. Solvent removable

2. Water washable

3. Post emulsifiable

4. None of the above

The correct answer is: Water washable

The most suitable penetrant process for parts with keyways and threads is the water-washable method. This process involves using a water-based cleaner to wash away the excess penetrant from the surface, which is particularly beneficial in complex geometries like keyways and threads where debris can accumulate. Water-washable penetrants are designed to be more easily removed during the wash stage without the need for solvent, making it a practical choice for parts that may be more sensitive to chemical exposure. This method allows for effective detection of surface discontinuities while minimizing the risk of leaving residual penetrant that could interfere with function or further processing of the parts. In contrast, solvent-removable penetrants may not be as effective in these tight areas since the solvent can sometimes be unable to completely wash away the penetrant from intricate features. Post-emulsifiable methods involve a more complex process that may not be favorable for quick assessments in threaded and keyway regions, where efficiency and thorough cleaning are primary concerns. Hence, the water-washable process stands out as the most suitable choice for such applications.