Penetrant testing with water-washable penetrants
Capillary testing with water-washable penetrants is a dye penetrant method in which excess penetrant is directly rinsed off with water. This shortens the process time and improves test accuracy.
Physico-chemical mechanism of action
Capillary testing uses a water-washable penetrant that penetrates into the cracks or holes of the material. After penetration, the material is cleaned with water, which removes the excess penetrant and gives a visible indication of defects.
Metallurgical relevance & risks during welding
This test is particularly useful for checking cracks or holes in metals because it offers high resolution and precision. However, an incorrect penetrant or insufficient cleaning can result in missed or false readings.
Workshop practice & instructions
1. Penetrant application: Apply the water-washable penetrant to the material to be tested and allow it to soak for at least 5 minutes.
2. Cleaning: Rinse the material with water to remove excess penetrant.
3. Drying: Allow the material to dry or wipe it with a clean cloth.
4. Visual inspection: Defects are now visible and can be photographed or documented with a magnifying glass.