Thread Content
The conveyor belt plays a role in traction and load carrying in belt conveyors; it is the main working component of the conveyor, and its motion state determines the continuity and stability of material transport by the conveyor. During operation, frictional wear occurs between the conveyor belt and rollers, idlers, as well as the material itself. It was learned from the mine site that the wear on the conveyor belt is more severe 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 its speed increases, the relationship between the non-loading surface of the belt and the idlers is no longer one of pure rolling friction as theoretically assumed; sliding friction also occurs. Especially when individual idler rollers fail to rotate smoothly or even stop rotating due to certain reasons (such as poor bearing lubrication), sliding friction becomes more apparent, while the frictional wear on the bearing surface is primarily caused by interaction with the material (coal). Throughout the entire transportation process, except for the brief sliding friction, and even 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-load-bearing surface that suffers more severe wear; often, the steel wires become exposed on the non-load-bearing surface even when the load-bearing 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, and up to 10 million tons at most. Nationwide, the annual expenditure on 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, especially 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 belt can be repaired. By using repair materials with excellent adhesive properties, the conveyor belt can be restored to its original condition, and friction between the original belt material and the idlers can even be reduced, thereby maximizing the belt’s service life. Our company uses two types of 100% solid-based, shrink-resistant polyurethane repair materials in the form of paste, packaged in cans or other formats suitable for use on site. This repair material is highly effective for fixing damages in products with elastic properties, such as rubber, polyurethane linings, conveyor belts, and insulating layers on pulleys. 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, being non-toxic and odorless, resistance to media, aging resistance, high bonding strength, and high insulation strength ； After curing, it exhibits high toughness, wear resistance, corrosion resistance, as well as excellent resistance to impact wear and cavitation. The series of polyurethane adhesive repair materials exhibits excellent adhesion properties. Different primers and adhesives are formulated for various substrates; thus, suitable primers and adhesives can be found for all metal and non-metal substrates. After being mixed in the proper proportions, polyurethane repair material can be applied to form coatings of any thickness. Since the material contains no volatile components, the coatings do not shrink. The cured surface can be machined or polished to achieve a relatively smooth surface. These characteristics make it easier to achieve a smooth repair surface that is consistent with 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 sealing and repairing longitudinal and transverse tears in rubber products, steel-reinforced products, as well as 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, insulation sealing, and repair of cables, rubber linings, tires, rubber impellers, rubber rollers, and other rubber products ； It can also be used for the preparation of rubber lining coatings that provide equipment with resistance to cavitation, protection against cavitation, as well as resistance to impact and wear.