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This post was last edited by PU3618988 on 2022-8-24 at 15:54. During use, the surface of a vibrating tray is subject to continuous friction and impact from various components; therefore, a wear-resistant coating is applied to its surface to extend its service life. Such a coating must have properties such as noise reduction, wear resistance, and good elasticity. Especially metal parts, which are usually at high temperatures and coated with organic oils, require coatings that offer oil resistance and heat resistance; in most cases, spraying polyurethane elastomers is used for this purpose. Generally, a layer of adhesive is sprayed or applied to the surface of stainless steel or steel vibration trays in order to enhance the adhesion between the wear-resistant layer and the base surface. All surfaces must be clean and dry, free from moisture, dust, oil, greases, surface chemicals, and other contaminants. For surfaces made of metals such as stainless steel or steel, the surface must be polished to improve adhesion; thereafter, a wear-resistant coating material is sprayed onto it. Therefore, an excellent wear-resistant coating material and adhesive for such applications need to possess properties such as strength, elasticity, flexibility, wear resistance, heat resistance, and solvent resistance. How to choose high-quality and suitable wear-resistant coating materials? 1. Wear resistance. The primary factor. Identification + testing. A simple method of identification is to use a metal object that is not extremely sharp, such as a key, to simulate the abrasive agents present under operating conditions, and to conduct scratching tests on the surfaces of ordinary coatings as well as wear-resistant polyurethane coating samples, comparing the results. 2. Flexibility. The criteria for judgment refer to the parameters of tensile strength and elongation. The higher the strength and the greater the elongation, the better the flexibility. That is, the greater the ability to recover from stretching or bending. Under physical changes such as gravity or high temperatures, the coating does not crack or break, maintaining its original protective properties, which primarily refer to its performance in the horizontal direction. 3. Elasticity. It mainly refers to the ability to recover deformation in the vertical direction. Excellent elasticity not only protects the protective equipment beneath the coating but also safeguards the materials on top of the coating. Identification: The depth can be roughly estimated using the pressing method. 4. Adhesion. The adhesion strength (firmness) between the coating and the substrate. This is the basic factor for judging the quality of a product. The coating must adhere firmly to the substrate in order to exhibit its above three properties. As a medium between the substrate and the wear-resistant adhesive, the primer can **enhance the adhesion between polyurethane elastomer products and the substrate. 5. Thixotropy. That is, the anti-sagging property, which is key to ensuring uniform coating thickness. It can be applied on elevations or surfaces with complex shapes, which is particularly important for small components. Especially at 90-degree angles, such as in the corners of the vibrating tray, the coating still remains even on the products. Even coating is one of the most important prerequisites for ensuring the durability of products. 6. Appearance. Excellent thixotropic properties are an important factor for a smooth appearance. After installation, the surface of the product is smooth, without any particles or unsightly textures. It will also not slip. 7. Operability. That is, during the construction period, there are few restrictions on the product pairs regarding the construction environment and temperature. 8. Security. Some vibration bowl devices are used in applications such as walnut peeling equipment and grain silos, as well as in places that come into contact with food or pharmaceuticals, and they need to meet food-grade certification standards. Given the eight requirements that the wear-resistant layer required for vibration trays must meet, spray-applied polyurethane elastomers can fully satisfy these needs, as such coatings possess the following properties: corrosion resistance, wear resistance, high flexibility, and excellent elasticity. In submerged conditions, their wear resistance is 8 times that of cemented carbide steel, 7 times that of vulcanized rubber, and 3 times that of ultra-high molecular weight polyethylene. Excellent physical and chemical properties, such as tensile strength, elongation, flexibility, wear resistance, aging resistance, and corrosion resistance. The formula can be adjusted as needed, ranging from soft rubber (Shore A30) to hard elastomers (Shore D90), to meet various operational requirements. It has excellent corrosion resistance, capable of withstanding the erosion of acids, alkalis, oils, water, and other substances with a pH range of 3–11. Its anti-corrosive properties are outstanding. It features high resistance to salt spray corrosion and excellent freeze resistance, allowing for normal operation over a wide temperature range of -57°C to 93°C. Special models can withstand high temperatures up to 170°C. Exceptional adhesion performance: Different primers and adhesives are used depending on the substrate, ensuring that there is a suitable primer and adhesive for all metal and non-metal substrates. Self-leveling, no sagging: It cures quickly, does not contain catalysts, and can be sprayed onto any curved, inclined, or vertical surface without causing sagging. Its gelation time is short – walking strength is achieved within just a few dozen minutes. Aesthetic appearance: Various colors and dyes can be added to create products of different colors; as a result, the surface remains clean, has an attractive appearance, and does not fade over time. It has good prototype reproducibility; the coating is continuous and dense, with no seams or pinholes. It is aesthetically pleasing and practical, offering excellent UV protection. Simple to construct, can be carried out at room temperature: insensitive to humidity and temperature, and causes no pollution. Using a complete set of equipment makes construction convenient and highly efficient ； The design thickness requirement can be achieved in a single application, and the range of spraying equipment meets the various requirements for coating different components. Eco-friendly paint: two-component, 100% solid content, environmentally harmless, free of any volatile organic compounds (VOCS). This product has been recognized as eco-friendly by relevant agencies in the United States and Europe; it contains no toxic volatile substances and meets the food-grade standards of the United States and Europe. It can also be widely used in the food and pharmaceutical industries. Therefore, the properties of spray-type polyurethane elastomers fully meet the requirements for wear-resistant coating materials in mechanical devices such as vibration feeders, making them an excellent choice for wear-resistant materials in these devices.