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

Which type of developer should not be used with a visible dye penetrant process?

1. Dry

2. Non-aqueous wet

3. Water soluble

4. Water suspendable

The correct answer is: Dry

The choice of dry developer in the context of a visible dye penetrant process is significant because dry developers create a powdery layer that can absorb excess penetrant and enhance visibility of indications. However, when using visible dye penetrants, the application of a dry developer can hinder the process. This is because the dry developer may not adequately draw out the penetrant from defects, leading to less pronounced indications or missed defects altogether. In contrast, non-aqueous wet developers, water-soluble developers, and water-suspendable developers are specifically designed to work with visible dye penetrants by promoting the removal of excess penetrant while enhancing clarity of the indications. Non-aqueous wet developers can help clean and reveal indications more effectively, while water-soluble and water-suspendable variants facilitate the combination of developer and penetrant in a way that provides better visibility of any flaws present, making them suitable for visible dye penetrant testing. By avoiding the use of dry developers with visible dye penetrants, one ensures that the detected indications are clear and effectively highlighted, which is crucial for accurate interpretation and assessment during testing.