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The Oxford Dictionary defines a chute as an inclined channel or slide used to transfer items to a lower height; transfer chutes are involved in the transfer between conveyors, as well as in aspects such as the stacking and removal of bulk materials and various process requirements. Chutes are used in almost all processes for handling bulk solid materials; if they are not properly designed and maintained, it can result in the system being shut down for 12 to 16 weeks per year, and the maintenance cost of a single transfer chute can amount to several million yuan. Common problems that arise during the use of chutes include: turbulence of the material in the feeding area, belt deviation caused by misalignment in feeding, poor sealing at the skirt plates, rapid damage to the buffer idlers, material spillage and dust leakage due to insufficient height or length of the skirt plates, fragmentation of materials such as coal, coke, and grain particles as a result of material degradation, severe wear on the chutes and conveyor belts, damage and wear to the conveyor belts caused by large pieces of material, blockages due to accumulated material, structural support defects in the chutes and skirt plates, and corrosion of the components in the transition sections. The root cause of these problems lies in the design flaws of the transfer chute. To address the aforementioned issues, designers Stuart-Dick and Royal outlined 6 design principles for bulk material transfer chutes, while designer Roberts also identified issues that need to be considered in the design, as summarized below. (1) Avoid blockage at the impact point: It is necessary to ensure there is sufficient distance between the discharge drum and the impact point on the chute, in order to prevent the material from bouncing back after hitting the chute and causing it to move upward. The chute must have a sufficient inclination angle; in the iron ore industry, a minimum inclination angle of 65°–70° is generally required, with design specifications calling for an angle of over 55°. (2) Ensure sufficient cross-section: It is generally required that the cross-section of the discharge pipe be 3 to 4 times that of the material being transferred. There is a contradiction here: the larger the cross-section, the smoother the flow of material, and it is less likely to experience blockages ； On the other hand, an excessively large cross-section causes the material flow to diverge, leading to greater dust problems, so a compromise needs to be found. (3) Controlling particle flow: The material flow should be kept relatively concentrated; generally, it is required that the material falls vertically after passing through the upper guide plates. Additionally, it is necessary to ensure that the material is fed evenly onto the receiving conveyor, in order to avoid issues such as belt deviation and material spillage caused by uneven loading. (4) Minimize friction on the chute surface: To ensure smooth material flow, it is generally required that the surface of the chute be smooth. Since the material causes wear on the lining plates as it passes through the chutes, the surface of these lining plates becomes smoother due to friction; therefore, some designs require that the lining plates be polished before installation, in order to maintain a constant level of friction between the newly installed lining plates and the material. (5) Controlling dust generation: Dust control is primarily achieved by maintaining contact between the material and the surface of the chute, thereby concentrating the material flow and ensuring a low impact angle. The material should move at a steady speed as it passes through the chute, and when fed onto the receiving conveyor, its velocity should be consistent with that of the conveyor belt. (6) Controlling material degradation: For materials that are prone to breaking, it is necessary to control the flow rate of the material in order to minimize collisions between the particles. Some of the aforementioned design principles are mutually restrictive, and preventing blockages in the transfer chute is the primary concern, as such blockages result in the loss of functionality of the transfer chute.