Thread Content
Common problems that occur during the use of conveyor belts include scratches caused by foreign objects, localized damage from such objects, and wear. Typically, conveyor belts suffer local damage due to foreign objects; according to traditional methods, they have to be disassembled, repaired through heating and vulcanization, or discarded and replaced. It was learned from the mine site that the conveyor belt wears out more severely on the non-load-bearing surface, which seems to contradict theory. After careful analysis, it is concluded that during the operation of the conveyor belt, as the conveyor speed increases, there is not only theoretical pure rolling friction between the non-load-bearing surface of the belt and the idlers, but also sliding friction. When individual idlers stop rotating due to certain reasons (such as poor bearing lubrication), the sliding friction becomes more pronounced, while the frictional wear on the bearing surface is mainly caused by contact with the material (coal). Throughout the entire transportation process, aside from the brief sliding friction and impact friction (during loading) at the times of loading and unloading, the conveyor belt surface and the material remain relatively stationary for most of the time. Therefore, in existing conveyor belts that operate at high speeds, it is the non-loading surface that suffers more severe wear; often, the steel wires become exposed on the non-loading surface even when the loading surface is still in good condition. Furthermore, as the speed of the conveyor belt increases, the frictional heat generated between the belt and the idlers and rollers also increases, which accelerates the wear of the non-load-bearing surface of the conveyor belt. At present, standard flame-retardant conveyor belts are used in coal mines in our country, with a coal handling volume of generally 6 to 8 million tons, sometimes reaching 10 million tons; the annual cost associated with these conveyor belts is estimated to be between 100 million and 200 million yuan. To increase the service life of the conveyor belt, it is first necessary to find ways to minimize friction on the belt, specifically sliding friction ； Secondly, when selecting the material for the conveyor belt, it is necessary to choose a material with low friction and high wear resistance. However, during mechanical operation, frictional wear of the conveyor belt is inevitable. The cost of replacing the conveyor belt is high; therefore, to save costs, the worn conveyor belt can be repaired. By using repair materials with excellent adhesive properties, it is possible to restore the conveyor belt, reduce friction between the original belt material and the idlers, and extend its service life. Two-component, solid-based, shrink-resistant polyurethane repair materials are available in paste form and come in canned or other packaging types suitable for use on-site. This repair material is highly effective for repairing damage in elastic products such as rubber, polyurethane linings, conveyor belts, pulleys, etc. Polyurethane repair materials are room-temperature curing, solvent-free polyether adhesive types ； It features fast curing speed, simple operation, ease of use, good filling properties, resistance to media, aging resistance, high bonding strength, and high strength ； After curing, it exhibits excellent toughness, wear resistance, corrosion resistance, as well as resistance to impact wear and cavitation. The polyurethane adhesive repair material series features strong adhesion properties; different primers and adhesives are used depending on the substrate, and suitable primers and adhesives can be found for both metal and non-metal substrates. After being mixed in the proper proportions, polyurethane repair material can be applied to form a thick coating; since the material contains no volatile components, the coating does not shrink. The cured surface can be machined or polished to achieve a relatively smooth surface. These features make it easier to achieve a smooth repair surface that matches that of the original substrate when carrying out surface repairs using polyurethane repair materials. Polyurethane repair materials can be used to address a variety of repair issues related to elastomers. They are primarily employed for repairing longitudinal and transverse tears in rubber products, as well as in steel-reinforced products and conventional conveyor belts, as well as for creating elastic joints ； Repair of surface wear, defects, chipping, edge wear, and perforations on conveyor belts, as well as sealing of joints ； Bonding, sealing, and repair of cables, rubber linings, tires, rubber impellers, rubber rollers, and other rubber products ； It can also be used in the preparation of rubber lining coatings that provide equipment with resistance to cavitation, protection against cavitation, as well as resistance to impact and wear. Polyurethane repair materials can be used to address the repair of elastomers. Below are some representative examples of using polyurethane repair materials for repairing substrates: Repairing tapes – fixing edge damage, wear on tape adhesives, and providing bottom protection; repairing longitudinal cracks; protecting areas where tapes are twisted together; covering rollers with adhesive; repairing and protecting the joints where rollers are covered with adhesive; repairing rubber idler rollers; quickly repairing torn tape edges; quickly repairing rubber linings such as those in chutes and feeders; serving as a filler between thin sheets of rubber or polyurethane/polyurea materials; repairing container linings (with lining materials such as rubber, PVC, glass fiber, or polyurethane/polyurea materials); repairing rubber strip linings in ball mills; repairing linings for pumps, impellers (blades), or valves; serving as a lining for pumps or valves; repairing off-road vehicle tires; quickly repairing slides, floats, car bumpers, oars, etc. in amusement parks; repairing sealing devices in high-power power supply boxes, such as those in power plants; quickly repairing the linings of wastewater treatment equipment; quickly repairing rubber connections in processing equipment or various related field devices; quickly repairing small holes in chutes and feeders (such repairs cannot be carried out when dealing with flammable materials like coal, or during welding or burning operations)