What is the recommended method for removing the oil phases from parts prior to penetrant application?

The recommended method for removing oil phases from parts prior to penetrant application is vapor degreasers. Vapor degreasing is particularly effective as it utilizes the evaporation of solvents to dissolve and remove oils and greasy residues from the surface of the components. This method is efficient in eliminating contaminants from intricate geometries and hard-to-reach areas, ensuring that the surface is adequately prepared for subsequent penetrant application.

Vapor degreasers typically involve non-aqueous solvents that, when vaporized, condense on the cold parts, allowing for superior cleaning and the removal of surface contaminants without leaving residues. This is particularly important in liquid penetrant testing, as any remaining oil film could obscure defects or impact the quality of the penetrant inspection.

While other methods such as solvent wiping and high-pressure water jets can also be used to remove contaminants, they may not be as effective as vapor degreasing for achieving a completely clean and residue-free surface, which is crucial for reliable penetrant testing. Soap and water may not adequately remove all oil phases, especially in industrial applications where heavier oil or grease is involved. Thus, vapor degreasers are preferred for ensuring optimal surface preparation before penetrant application.