What is the best method for drying parts after the application of a wet developer?

The best method for drying parts after the application of a wet developer is to use circulating air at a maximum of 71 °C (160 °F). This method provides controlled drying, ensuring that the developer does not lose its effectiveness or cause any unwanted reactions or residues on the test surface.

Drying with circulating air helps to maintain an even temperature distribution, which is important for effective drying without risking damage to the part being tested. The maximum temperature limit of 71 °C (160 °F) is set to prevent thermal degradation of the penetrant material or the substrate, as excessive heat can negatively impact the surface characteristics and the penetrant’s ability to reveal flaws.

In contrast, drying under direct sunlight can lead to uneven heating and may introduce contaminants. Using a hairdryer might generate localized heat that could also cause thermal stress or uneven drying. Wiping with a dry cloth can remove developer but may leave residues or introduce contaminants, which could interfere with the clarity of the inspection results. All these alternatives lack the controlled environment necessary for optimal drying post-application of a wet developer.