What is the function of the emulsifier in post-application of penetrants?

The function of the emulsifier in post-application of penetrants is crucial for achieving clear and effective results in Liquid Penetrant Testing. When penetrant is applied to a part, it seeps into any surface discontinuities such as cracks or porosity. After the dwell time, the excess penetrant must be removed for the inspector to visualize the defects accurately.

The emulsifier plays a vital role in this process by aiding in the removal of excess penetrant. It interacts with the penetrant and converts it into a wash, making it easier to clean off the surface without disturbing the penetrant that has already penetrated into the defects. This ensures that the surface is clear and that the indication of any defects remains sharp and visible, allowing for accurate inspection and assessment. By effectively removing the excess while leaving the penetrant in the defects, the emulsifier enhances the quality of the inspection results.