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Bucket elevators include belt bucket elevators, plate-chain bucket elevators, chain bucket elevators, and others. They are vertical lifting devices widely used in agricultural product processing plants and grain agencies. They offer advantages such as a large lifting height, stable operation, low floor space requirements, and good sealing properties, making them suitable for transporting powdered and small lumpy materials. The following are some common faults that occur during the use of this equipment: 1. Slipping of the conveyor belt. (1) A bucket elevator relies on the frictional torque between the conveyor belt and the drive shaft of the head pulley to lift materials; if the tension in the conveyor belt is insufficient, it will cause the belt to slip. At this point, the machine should be stopped immediately, and the tensioning device adjusted to tighten the hopper belt. If the tensioning device is unable to fully tension the hopper belt, it means that the travel distance of the tensioning device is too short, and it should be adjusted again. The correct solution is to loosen the connections of the conveyor belt, adjust the tensioning device on the idler wheel to its highest position, feed the conveyor belt in from the head of the elevator, pass it through the drive wheel and the idler wheel, and connect its ends together so that the conveyor belt is in a state of being tensioned but not overly tight. Then fully tension the tensioning device. At this time, the tensioning stroke of the adjustment screw of the tensioning device that has not yet been utilized should be no less than 50% of the total stroke. (2) Overloading of the elevator: When the elevator is overloaded, the resistance torque increases, causing the bucket belt to slip. At this point, the feed rate of the material should be reduced, and efforts should be made to ensure uniform feeding. If slippage does not improve even after reducing the feed rate, it may be due to too much material accumulated inside the machine or the hopper being blocked by debris; the machine should be stopped for inspection in order to resolve the issue. (3) The inner surfaces of the head pulley shaft and the conveyor belt are too smooth; this reduced friction between them, resulting in slippage of the conveyor belt. At this time, a layer of glue can be applied to the drive shaft and the inner surface of the hopper belt to increase friction. (4) Poor rotation of the drive wheel and idler wheel bearings: When these bearings do not rotate properly, the resistance torque increases, causing the conveyor belt to slip. At this time, the oil can be drained and refilled or the bearings can be replaced. 2. Deviation of the hopper belt (1) Improper installation of the drive shafts for the head wheel and the bottom wheel. The improper installation of these drive shafts is manifested in the following ways: first, the drive shafts of the head wheel and the bottom wheel are not parallel and lie in the same vertical plane; second, both drive shafts are installed horizontally but are not in the same vertical plane; third, the two drive shafts are parallel, lie in the same vertical plane, but are not horizontal. At this time, the hopper belt deviates from its path, which can easily lead to collisions between the hopper and the barrel, as well as tearing of the hopper belt. The machine should be shut down immediately to resolve the fault. It is ensured that the drive shafts of the top wheel and the bottom wheel are installed in the same vertical plane and are both in a horizontal position; the vertical deviation of the machine’s centerline at a height of 1000 mm does not exceed 2 mm, and the cumulative deviation does not exceed 8 mm. (2) Incorrect hopper belt joint: An incorrect hopper belt joint means that, after the hopper belt is joined together, the edges of the belt are not on the same straight line. During operation, the belt of the hopper becomes tight on one side and loose on the other, causing the belt to shift toward the tight side and resulting in deviation. This leads to insufficient filling of the hopper, incomplete unloading, increased backflow of material, and reduced productivity; in severe cases, it can cause the belt to get stuck or tear. At this point, the machine should be stopped to repair and reconnect the joint properly. 3. Excessive return material: Return material in the elevator refers to the phenomenon where the material is not completely discharged outside the machine at the discharge point, and some of it returns into the elevator’s frame. In lifting operations, if too much material returns to the elevator, it will inevitably reduce production efficiency, increase power consumption, and raise the rate of material fragmentation. The reasons for excessive return material are as follows: (1) The speed at which the hopper operates varies depending on the type of material being lifted. Generally, when lifting dry powders and granules, the speed is around 1–2 m/s; when lifting bulk materials, the speed is 0.4–0.6 m/s; and when lifting wet powders and granules, the speed is 0.6–0.8 m/s. The speed is too high, resulting in premature unloading and thus backflow of material. At this time, the speed of the hopper should be appropriately reduced depending on the material being lifted, to avoid backflow. (2) The unloading tongue plate at the machine head outlet is not installed properly; it is too far from the unloading position of the hopper, which causes material to flow back. The position of the tongue plate should be adjusted promptly to prevent backflow. 4. Hopper detachment: Hopper detachment refers to the phenomenon in production where the hopper falls off the conveyor belt. When the hopper falls, it produces an abnormal noise, and the machine should be stopped for inspection promptly; otherwise, more hoppers will become deformed or fall off. At the connection points of the hoppers, the belts used to hold them can tear. The main reasons for the bucket to fall off are: (1) Excessive feeding, which leads to the accumulation of material inside the frame, increases the lifting resistance, and hinders the proper operation of the bucket; this is the direct cause of the bucket falling off or becoming deformed. At this point, the machine should be stopped immediately, the plug under the base should be removed to drain the accumulated material inside the base, a new hopper should be installed, and then the machine can be restarted for operation. At this point, reduce the feeding amount and strive for uniformity. (2) Generally, the feed inlet is positioned too low; during production, the conveyor bucket automatically picks up the material that enters through the feed inlet. If the feed inlet is positioned too low, it will prevent the hopper from having enough time to collect the material, causing most of the material to go into the machine base instead, which hinders the hopper’s ability to scoop up the material. And when the material is in block form, it can easily cause the hopper to deform or fall off. At this time, the feed inlet position should be adjusted above the centerline of the bottom wheel. (3) The material of the hopper is of poor quality and has limited strength. The hopper is a component that bears loads in the elevator, so high requirements are placed on its material; when installing it, it is necessary to use materials with good strength as much as possible. Generally, hoppers are welded or stamped from ordinary steel plates or galvanized sheets, and their edges are folded or wrapped with wire to enhance the strength of the hopper. (4) Failing to remove the accumulated debris from the machine base when starting up. During production, sudden power outages or other issues that cause the machine to stop operating are common; if the accumulated debris in the machine base is not removed before restarting, it can lead to excessive stress on the hopper, resulting in its breakage and detachment. Therefore, between shutdown and startup, the accumulated physics inside the chassis must be cleared to prevent the hopper from falling off. Additionally, regularly check whether the connection between the hopper and the conveyor belt is secure. If loose screws, missing screws, or a tilted or damaged hopper are detected, repairs or replacements should be carried out promptly to prevent more serious accidents. 5. Hopper belt tear: The hopper belt in bucket elevators is usually made of canvas, though tape and chains are also used sometimes. Under the combined effect of various faults, canvas belts and tapes are prone to tearing, which is one of the most serious faults. Generally, the deviation of the bucket belt and the detachment of the bucket are the processes that most easily cause tearing of the bucket. The cause should be identified promptly and thoroughly to resolve the fault. Furthermore, the presence of foreign objects with sharp edges in the material can also cause cracks in the hopper. Therefore, in production, wire mesh or magnets should be installed at the feed inlet to prevent large foreign objects from falling into the machine base.