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I. Functions of screw conveyors Thanks to their unique structural features, screw conveyors have multiple functions. The first is transportation; the second is air sealing, and they can also be used for metering. Its conveying mechanism involves pushing the material forward as the spiral blades rotate; air sealing is achieved through the small gap between the blades and the casing, as well as through the compaction of the material or its accumulation due to the variable pitch, such as in seal augers and screw pumps ； Measurement is achieved by combining weighing and rotation speed, as in single-tube measuring twisters. II. Structural components of the screw conveyor: The screw auger features a simple structure and reliable operation, and is widely used in various industries. It mainly consists of a housing, screw blades, an auger shaft, intermediate support brackets, end bearing housings and supports, couplings, as well as a reducer motor and inlet/outlet ports. III. Inspection items for screw conveyors Although screw conveyors are simple, inspections are essential and mainly include the following aspects. 1. Inspection of the housing: When inspecting the housing, first check whether there is any misalignment in the upper cover, dust leakage, shaking of the housing, wear and tear on the housing, or other defects. 2. Lubrication check: Check the reducer or geared motor to ensure that the oil level is appropriate, and verify that there is enough oil in the oil reservoirs of the suspension brackets. Image 3. Transmission inspection. The transmission inspection includes the reducer, motor, and coupling. The main checks include whether the anchor bolts of the reducer, motor, and coupling are loose, whether the temperature and vibration levels of the reducer and motor are normal, whether there are any abnormal noises, and whether the lubrication is adequate. 4. Support device inspection: The support devices refer to the two main bearings at the front and back, as well as the intermediate suspension bracket. It mainly checks the bearing vibration, temperature, lubrication condition, etc. IV. Maintenance of screw conveyors: Maintenance primarily involves addressing issues identified during inspections or carrying out regular upkeep of the equipment, which can be summarized in several aspects. 1. Regularly perform quantitative, targeted, and quality-controlled oiling and lubrication of the equipment. 2. When the casing is found to be shaking, it may be due to loose foundation bolts, loose suspension bracket bolts, or damaged suspension bracket bearings. The foundation bolts and suspension bracket fixations should be tightened; if the suspension bracket or the main bearings at both ends are damaged, the machine should be shut down promptly or scheduled for shutdown in order for replacement to take place. It is also possible that large pieces or foreign objects are stuck between the blade and the housing; the machine should be stopped for cleaning. 3. If there is a frictional noise coming from inside the casing, it may be due to damaged bearings in the intermediate suspension, blades that have sunk, or loose suspensions that cause friction with the casing; the machine should be stopped to replace the bearings or tighten the suspensions ； If there is debris stuck between the blade and the housing, stop the machine and clean it out. If the noise comes from within the bearing, it is likely due to dust accumulation or a lack of oil in the bearing; cleaning it and adding oil should resolve the issue. 4. Ash leakage from the screw conveyor: When ash leakage is observed, it is usually caused by poor sealing or insufficient negative pressure in the conveyor unit. The leaking area should be sealed, and if possible, the valves on the dust collection pipeline should be adjusted to increase the exhaust volume. If ash leaks from the machine, the worn areas should be sealed up, and it is necessary to check whether the discharge channel is unobstructed in order to prevent accumulation of material inside the casing, which could lead to leakage. It is also important to check whether the amount of feed is excessive, exceeding the design capacity of the auger; if so, the situation should be resolved by making appropriate adjustments. At the same time, check whether the motor is operating with a missing phase, etc. 5. Breakage of the cross coupling: The breakage of cross couplings is often caused by necking or overload; it is necessary to prevent foreign objects from entering the machine chamber, and such objects should be removed when replacing the coupling, along with ensuring proper alignment. 6. Transmission faults: If there are abnormal noises or excessive temperatures in the reducer, it is usually caused by damaged internal bearings or faulty gears. The components should be opened for inspection, replaced, or repaired, and proper lubrication must be ensured. In the event of oil leakage, the seals should be checked and repaired, and the ventilation openings must remain unobstructed. If the motor produces excessive noise and has a low speed, it is usually caused by a missing phase or overload; the cause should be identified promptly and repairs carried out. If there is transmission vibration but the noise is normal, check whether the footings are loose. 7. Others: In addition to regular repairs and maintenance, it is also necessary to ensure that the cement remains clean and hygienic; there should be no unstable substances in the moving parts. It is also important to monitor the electric current and the load on the equipment.