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CORROSION bats corrosion from both immersion and atmospheric exposures and can be applied at temperatures as low as 0°F (-18°C). A modified phenalkamine epoxy, Macropoxy 80 is recommended for use on water and wastewater tanks as well as structural steel, pipe, tanks and other equipment in industrial applications. Because of its surface tolerance, Macropoxy 80 can be applied in adverse conditions, and steel substrates need only to be cleaned of loose paint or rust (per SSPC SP2-3 Hand and Power Tool Cleaning) before application. Its high solids formulation (80%) reduces the likelihood of solvent entrapment that can lead to premature coating failure. and improved version of its SQ171E coating is thinner and provides longer-lasting protection against corrosion than the previous version, according to the company. SQ171E coating can be used for standard or special bearings as well as for all metal parts exposed to wet or corrosive environments. According to NKE, even machined surfaces such as races can be coated, and the treatment provides protection against water, condensation and slight- ly alkaline or acidic cleaning agents. Compared to uncoated components, parts coated with SQ171E are claimed to have a significantly longer service life. As an additional option for even more effective protection the coating is also available with a silicate-based sealing layer. Due to the reduced thickness of the coating (from 2 to 4 µm) coated and uncoated parts are completely interchangeable. When compared to stainless steel, NKE says the SQ171E coating is Peel-off, or Permanent Not all coatings are made to last forever. For example, Spraylat International, a U.K.based company, offers the Protectapeel line of environmentally friendly coatings that are applied as a liquid by spray or roller and dry to form a skin-tight, plastic film that can be easily stripped away after use. According to the company, Protectapeel is often ideal for protection of metal during shipping or storage. The product is claimed to prevent rust from forming on the protected surface; when the items are ready to be installed or delivered the coating can simply be stripped off by hand, avoiding some common problems encountered with other protective products such as the need for solvent or hot-water cleaning to remove sticky residue, waxes or oils before the protected item can be used or installed. All Protectapeel coatings are water-based, making them safe for users and eliminating any need for special safety wear when working with the product. Other coatings are designed to be practically—or completely—invisible. For bearings and metal parts that are exposed directly to humid or corrosive environments, NKE Austria GmbH offers a special galvanic coating that provides cost-effective protection against corrosion. The new Removable coatings, such as Protectapeel, can be used for short- or long-term protection of metal items that must be shipped or stored in less-than-ideal environmental conditions. www.e-mj.com FEBRUARY 2013 • E&MJ; 51