Production Machining

SEP 2018

Production Machining - Your access to the precision machining industrial buyer.

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?????? Cleaning Slowing Corrosion :: 49 • Ferrous metal + corrosive gas (pollution) + moisture = rust • Nonferrous metal + corrosive gas = corrosion • (Often moisture does not play a factor in nonferrous corrosion.) To stop corrosion, one or more of the factors on the left- hand side of these equations must be stopped or hindered. To stop moisture from entering the packaging, air temperature changes should be minimized. Desiccants can be used to minimize the trapped air inside the package. To attack the metal part of the equations, the surface metal needs to be coated (with oil, for example) or painted; the moisture and corrosive gases must be kept away from the surface. To stop the corrosive gases from spreading to the parts, a hermetically sealed gas barrier that is free from folds, tears and holes, or a reactive gas barrier is needed. ere are four main classes of packaging materials: 1. Passive barrier bags, which tend to be foil bags that cannot be reused, recycled or often even resealed in the field. 2. Volatile protection bags, which use oils, emitter pads or single-pack bags because of proximity requirements. 3. P lain polybags with oils or emitters. 4. Reactive barrier bags, or gas-neutralizing bags, which use finely particulated copper that has been reacted onto the end chains of a polymer (plastic), creating a preferential corrosion site, as well as a reactive barrier to the gases that cause corrosion. Gas-neutralizing polyethylene plastics are fully reusable and recyclable, contain no volatile chemistry, have no odor, and neither use nor require oils. In addition, these materials have been tested by the German Automotive Industry and have been found to provide as much as 15 years of protection in one bag. Testing by the U.S. military also confirms that the material is effective in the temperature range of -42°F to 160°F. e world is getting more polluted; this increase in atmospheric pollution can and will accelerate corrosion on metal parts, so it is critical to isolate those metal surfaces from the atmospheric gases. In determining which packaging material is best for an application, considerations such as environment, cost, and health and safety are crucial. All metal has built-in corrosion protection; let packaging protect your items until they are required to be used, allowing their inherent corrosion protection to start from the time they are removed from the packaging. CONTRIBUTOR Keith Donaldson is president of Intercept Technolog y. Visit intercepttechnolog EFFICIENT CLEANING PERO R1 PARTS CLEANING PLANT energy-effi cient economical quick & reliable or call 860 298 0317 The standard cleaning plant PERO R1 provides technical cleanliness, degreasing and preservation especially Easy and economical parts cleaning PERO | ADVANCED PARTS CLEANING SYSTEMS Test clean your own parts in our competence center.

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