Definition
A cleaning process in which a metal part is suspended in the hot vapor of a chlorinated solvent. The vapor condenses on the cooler part, dissolves grease and oily contaminants, and drips off carrying the contamination away. The part emerges clean and dry without the need for wiping or rinsing.
Plain English
A way to clean greasy metal parts by hanging them in hot solvent fumes. The fumes turn back into liquid on the cool part, wash the grease off as they run down, and the part comes out clean and dry.
Context Anchor
Seen in aircraft maintenance, especially when parts must be cleaned before inspection, repair, bonding, painting, or assembly.
Derivation
From 'vapor' (the gaseous form of a liquid) and 'degrease' (to remove grease). The name describes the method exactly: grease is removed by the action of a vapor rather than by scrubbing or soaking in liquid.
Why Pilots Care
Parts cleaned this way arrive at inspection or assembly free of oily residue, which matters for tasks like nondestructive testing, bonding, and painting where any film of grease can cause a defect or a failed inspection.
Grounding Statement
Picture a cool metal part held over warm solvent vapor: the vapor touches the part, turns into liquid, and carries oil and grease off the surface as it runs down.
Intuition Check
Vapor degreasing does not mean cleaning with ordinary steam. Here, the vapor is usually from a cleaning solvent, and the cleaning happens when that vapor condenses on the part.
Example Sentence 1
The landing gear components were sent out for vapor degreasing before the magnetic particle inspection.
Example Sentence 2
Aircraft fittings are often cleaned by vapor degreasing to remove all traces of oil prior to fluorescent penetrant testing.