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This post was last edited by PU3618988 on 2021-12-1 at 16:15. Many minerals can be separated using magnetic separators, such as magnetite, limonite, hematite, manganese siderite, ilmenite, wolframite, manganese ore, manganese carbonate, metallurgical manganese ore, manganese oxide, iron ore, kaolin, and rare earth minerals. In China, due to the high proportion of low-grade iron ores (accounting for 97.5% of total reserves) and associated ores (accounting for 1/3 of total reserves), the hardness of the ore is relatively high. The magnetic drum surfaces of magnetic separators are constantly subjected to the impact of particulate iron ore particles with sizes ranging from 0 to 15 millimeters, resulting in severe wear; cracks in these drum surfaces occur frequently. Once the drum lining is worn through, the slurry enters the magnetic drum and adheres to the surface of the magnetic system, causing a seizure between the drum lining and the magnetic system; or the slurry gets into the bearings, leading to damage to those bearings and ultimately ruining the entire equipment. Currently, the wear-resistant material – spray-applied polyurethane elastomer – possesses not only the advantages of metal-based wear-resistant materials, such as high toughness, ease of application, high hardness, good plasticity, and excellent resistance to dynamic loads like bending fatigue and contact fatigue, but also the advantages of non-metallic wear-resistant materials, including low tendency to stick, high strength and wear resistance, corrosion resistance, and self-lubrication. Additionally, spray-applied polyurethane elastomer does not age easily, experiences low friction, and has a wide range of hardness levels (it can maintain high elasticity from Shore A30 to Shore D90). Sprayed polyurethane elastomer is a type of advanced polymer material with well-established manufacturing techniques, which can be widely used in mining, ports, power generation, coal mining, and other environments with challenging conditions to enhance the wear resistance and corrosion protection of mechanical equipment. Sprayed polyurethane possesses excellent properties such as wear resistance, corrosion resistance, impact resistance, salt spray resistance, aging resistance, flexibility, and strong adhesion. It is widely used in various mechanical devices such as vibrating screens, slurry pumps, magnetic separators, magnetic drum separators, and thickeners in mines. It is also suitable for use in industries such as cement plants, steel mills, fertilizer plants, and thermal power plants. The wear resistance of spray-applied polyurethane elastomers is 8 times that of cemented carbide steel, 7 times that of vulcanized rubber, and 3 times that of ultra-high molecular weight polyethylene. They can withstand the erosion of acids, bases, oils, and waters with a pH range of 3–11, offering excellent corrosion resistance ； It also possesses excellent adhesion properties; different primers and adhesives can be used depending on the substrate, and for all metal and non-metal substrates, there are suitable primers and adhesives available ； Construction is also very convenient: it can be carried out at room temperature, and it is not sensitive to humidity or temperature ； It causes no environmental pollution, contains no volatile organic compounds (VOCs), and is a new type of eco-friendly material ； Can cure rapidly at room temperature, without a catalyst ； It has an attractive color, good replication of the original shape, a continuous and dense coating without seams or pores.