Liquid Penetrant Testing Level 1 (PT-1) Practice Exam

Which of the following is NOT a generally accepted method for cleaning parts prior to penetrant testing?

1. Wipe with a cloth

2. Ultrasonic cleaning

3. Wire brushing

4. Solvent immersion

The correct answer is: Wire brushing

Wire brushing is not a generally accepted method for cleaning parts prior to penetrant testing because it can introduce scratches or damage the surface of the material being tested. The goal of cleaning before penetrant testing is to prepare the surface in a way that ensures any discontinuities can be effectively revealed by the penetrant. Wiping with a cloth is an acceptable practice since it can effectively remove contaminants without altering the surface significantly. Ultrasonic cleaning is also a valid method as it ensures thorough cleaning of complex geometries by reaching into crevices. Solvent immersion is frequently used as it efficiently removes oils, dirt, and other impurities that could obstruct the inspection results. In contrast, wire brushing may exacerbate any existing surface anomalies and may not fully eliminate all contaminants, potentially leading to false indications during the testing process. Therefore, it is inappropriate for use before penetrant testing.