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Belt tears in belt conveyors can generally be classified into two main categories: longitudinal tears and transverse tears. Longitudinal tears account for over 90% of all belt tear incidents. Therefore, we primarily focus on longitudinal tears and analyze their causes. Analysis of the causes of belt tearing in belt conveyors 1. Belt misalignment and tearing: When a belt conveyor is operating normally, its belt should be positioned along the central axis of the frame. However, when the belt deviates from this path, it tends to accumulate and fold on the side where it has shifted. Under the effect of uneven forces over time, the belt is prone to tearing. Generally, this situation occurs only on the side where the belt is misaligned, not on the inner side of the belt; it poses a relatively low threat to production safety. Moreover, such belt tearing has obvious precursors, and there is a considerable delay between the moment the belt starts to misalign and the point at which tearing occurs, so it can often be prevented through regular inspection and maintenance. 2 Tearing of the belt shaft core: When the conveyor is in operation, if it is subjected to a severe impact from large metal objects or gangue, it is possible for the steel core of the belt to break. If this broken core continues to be used, under the effects of prolonged stretching and loading, it may penetrate the belt and become exposed outside the belt’s cover rubber. When the exposed length of the steel core is long, it may get caught by components such as idlers and redirecting rollers while the belt is in operation, and be continuously pulled out as the belt moves, causing the belt to break. Another scenario is where the scraper of the head cleaner gets caught on the metal or other debris on the belt surface, wearing through the belt. To prevent such tears, it is necessary to strengthen inspections; whenever exposed wire rope ends are detected, they should be cut off immediately to avoid future problems. 3 Scratches and tears: Among longitudinal tears in belts, scratches and tears are the most common type, and they can generally be divided into two categories: scratches caused by sharp objects under pressure and penetrating scratches. The former case involves a large, long, sharp tool getting stuck at the bottom of the chute, and causing scratches on the belt as a result of the drive force exerted by the belt ； The latter refers to a sharp object falling from a certain height; under the influence of gravity, its tip penetrates the belt and gets lodged in the chute or idler. As the belt continues to move forward, it gets torn. 4. Blockage, jamming, and tearing caused by materials: This situation occurs at the lower part of the chute. Given the limited distance between the front edge of the chute and the belt surface, and the uneven distribution of idler rollers beneath the belt, the load-bearing capacity is inconsistent. When the projected length of the materials being transported on one side exceeds this distance, large pieces of material can become trapped between the front edge of the chute and the belt under certain circumstances; this exerts excessive pressure on the belt, leading to its tearing. Another scenario is when the feed rate at the loading point suddenly increases, causing blockage in the belt feeding process; if the system does not shut down as a result of this blockage, prolonged friction can lead to the tearing of the belt. Measures to prevent belt tearing: 1. Proactively prevent tearing at the source by strengthening quality control of materials and adding equipment for impurity removal. A large-piece removal device is installed in front of the primary belt to reduce the entry of large pieces of material into the entire conveying system. 2. Increase the throughput capacity of the chute: Given that the width of the chute is determined by the width of the belt, the outlet of the chute should be enlarged upwardly to maximize its throughput capacity, thereby preventing blockages caused by debris or large pieces of material. 3. Strengthen equipment management by increasing the frequency of inspections of belts, and pay special attention to the management of other auxiliary devices associated with belt conveyors, such as transfer hoppers and cleaners, in order to prevent sharp objects like liner plates from falling off. 4 Improve the conveyor structure by reducing the height difference at the material drop point, adding buffer grids, and ensuring that fine materials fall before larger pieces, thereby reducing impact, lowering the speed of the materials, and minimizing the likelihood of impurities getting trapped in the belt. 5 Improve the structure of the belt itself; for example, enhance the belt’s airtightness to prevent water from entering the core layer and the steel wires from rusting. Manufacturers are required to strengthen quality control in order to improve the quality of the belts. 6 Install a tear detection device: When the belt tears, it should be detected as quickly as possible, an alarm should be triggered and the machine should stop operating, in order to minimize the length of the tear and reduce losses. 7 Use tear-resistant belts. Tear-resistant belts use steel wire ropes as the longitudinal structural material, with horizontal reinforcement elements added to the belt body to serve as a tear-resistant layer; however, the cost of such belts is about 20% higher than that of ordinary belts. 8 Use belts that can detect tears. Sensors with closed loops are incorporated into the belts; these detectors are installed in the areas of the belt conveyor where tears are likely to occur, and they are connected to a controller. If the belt tears, the sensor’s closed loop is broken; when it passes by the detector, the detector ceases to emit pulse signals. The controller fails to receive these pulses, immediately triggers an alarm, and shuts down the system. At present, this type of belt cannot be produced domestically, and its cost is high.