Process
Cleaning – the Key to Successful Surface Preparation By: Venesia Hurtubise,Technical Chemist at MicroCare, LLC
Vapor degreasing prepares surfaces for painting, coating, or assembly.
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urface preparation can be the downfall for many metalworking machine shops if reliable procedures are not put in place to ensure parts cleanliness. Failure to properly prepare parts surfaces can lead to poor results in painting, coating, plating, and welding. Or it will simply affect the final appearance of the parts. The down-line effect of poorly prepped parts is a decline in production, parts quality, and parts reliability. An essential step to achieve a high-quality surface for finishing is cleaning. If a reliable and consistent cleaning procedure is not implemented, the quality of the metal parts may be substandard. The optimal metal cleaning process must successfully dissolve or displace common contaminants without damaging substrates and leave surfaces ready for the next stage of manufacturing. One of the most efficient cleaning methods to achieve perfectly prepped parts is vapor degreasing.
The Mechanics of Vapor Degreasing Vapor degreasing is a closed-loop system that requires two components: a closed-top vapor degreaser and a non-flammable, environmentally sustainable cleaning fluid. Most vapor degreasing systems are comprised of a top-loading batch-style cleaning machine with two compartments, “the boil sump” and “the rinse sump”. In the boil sump, parts are immersed in the heated fluid for cleaning. Once cleaned, the parts mechanically transfer to the rinse
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sump. The parts rinse in pure, uncontaminated fluid or inside the fluid vapors themselves. The parts come out dry and cool enough to easily handle. So, they are immediately ready for the next step in the process which may include assembly, painting, marking, labeling, or packaging. The cleaning fluids used within the system have multiple chemical properties that are advantageous to critical cleaning and surface preparation. The low viscosity and surface tension of modern cleaning fluids allow them to wet every surface getting into and out of tiny spaces to remove contaminant and residue. The fluids also offer high solvency and high density which enables rigorous surface cleaning and displacement of stubborn soils. Additionally, the fluid evaporates quickly out of complex parts geometries or difficult to reach areas like blind holes or small gaps. Unlike other cleaning methods which can leave behind unwanted stains or moisture that can cause corrosion, vapor degreasing ensures the surface is spot-free and dry.
Selecting the Correct Cleaning Fluid The industrial manufacturing sector has a wide variety of cleaning needs. Contaminant varies from machining oils, metal fines, and cutting or polishing fluids, to greases, fingerprints, and waxes. To successfully remove the contaminant, specific cleaning fluid types should be specified to dissolve or displace soils leaving parts thoroughly clean.
