I. General Provisions

1. These specifications apply to the operation and management of belt conveyors (including fixed and mobile types) in fertilizer production workshops, covering the entire process of pre-production preparation, production operation, and maintenance.
2. Operators must pass training before taking up their posts. Before operation, they shall become familiar with the equipment structure and the contents of these specifications. Drinking alcohol within eight hours before the shift and during the shift is strictly prohibited. Labor protection articles must be worn as required.
3. The belt conveyor mainly consists of a conveyor belt, drive pulley, bend pulley, idlers (including trough idlers, parallel idlers, impact idlers, and self-aligning idlers), tensioning device (screw take-up or gravity take-up), cleaners (head cleaner and return-strand cleaner), frame, motor reducer, and safety guards. Continuous conveying is achieved through the friction between the belt and the drive pulley, stably conveying fertilizer granules from the feed end to the discharge end. It is key conveying equipment connecting each process in the fertilizer production line.

II. Pre-Production Preparation Stage

2.1 Pre-Startup Inspection

1. Equipment integrity inspection: Check whether all parts are installed securely and whether fasteners are loose or fallen off. Check the belt for abnormalities such as fuzzing, cracking, and joint damage. Remove debris and accumulated material from the belt and frame area. Before restarting equipment that has been out of service for a long time (over 30 days), test the motor insulation with a megohmmeter.
2. Belt tension inspection: Check whether the belt tension is appropriate. Too loose easily causes slipping and deviation; too tight aggravates wear and increases motor load. Adjust to an appropriate level before startup. For gravity take-up devices, check whether the counterweight has landed and whether the counterweight is appropriate.
3. Idler and pulley inspection: Check whether all idlers rotate flexibly, have no adhered material, and are not damaged (such as bearing seizure or deformation). Check whether the drive pulley and bend pulley surfaces are clean and check the wear condition of rubber lagging (if any). The pulley surface must not have severe wear or deformation.
4. Cleaner inspection: Check the contact between the belt cleaners (head cleaner and return-strand cleaner) and the belt. If severely worn, adjust or replace them in time.
5. Lubrication system inspection: Check the lubrication condition of each bearing housing and reducer. Add sufficient lubricating oil to each lubrication point as specified. Check the oil quality and oil quantity of the electric drum (if applicable); the oil level should be within the range indicated by the oil sight gauge.
6. Electrical inspection: Power connections should be firm and reliable, insulation should be good, and grounding should be correct. Check whether the motor junction box and control box are well sealed, with no water ingress or moisture.
7. Safety device inspection: Check whether safety devices such as emergency stop pull cord switches, deviation switches, slip switches, and tear detection switches are intact and effective (if equipped). Check whether the emergency stop pull cord is flexible and reliable. The pull cord switch must be tested once per shift, and production may begin only after confirming normal action.
8. No-load trial run: For newly installed or overhauled equipment, after startup first check whether the rotation direction is correct (if reversed, stop immediately and adjust). Feed material only after confirming smooth operation, no abnormal noise, and no friction noise. Newly installed equipment should undergo a no-load trial run of no less than 2 hours.

2.2 Material Preparation

1. Confirm that the material to be conveyed contains no hard foreign matter such as iron blocks, stones, or broken packaging, so as to avoid scratching the belt or damaging the equipment.
2. Check whether the feed inlet discharges uniformly and whether the material is centered within the belt width, avoiding severe offset load.
3. The material temperature should be within the allowable range of the equipment. Excessive temperature will accelerate belt aging.

III. During Production Operation

3.1 Startup Sequence

1. This machine must be started under no-load conditions. Startup with material is strictly prohibited. Feeding first and then starting is prohibited.
2. When several conveyors operate in series, start from the discharge end and start in sequence against the material flow direction, that is, the last conveyor starts first, and then start progressively forward.
3. After confirming that the equipment runs smoothly, start the upstream feeding equipment to begin feeding.

3.2 Operation Monitoring

1. Belt status monitoring:
   • Continuously observe whether the belt deviates, slips, or vibrates abnormally. When belt deviation occurs, promptly use self-aligning idlers or the tensioning device to adjust. Do not force operation, so as to avoid edge wear and increased load.
   • When belt deviation exceeds 5% of the belt width, adjust immediately. In case of severe deviation or slipping, perform emergency shutdown.
   • Check the belt for damage, delamination, or breakage. Stop immediately if any problem is found.
2. Temperature monitoring:
   • During operation, pay attention to the surface temperature of the motor and reducer. The motor housing temperature must not exceed 70°C (for Class F insulation motors, the allowable temperature rise shall follow the nameplate). The reducer bearing temperature must not exceed 80°C. If exceeded, stop immediately and inspect.
   • Touch the bearing housing with the back of the hand to feel whether the temperature is abnormal; generally it should not exceed ambient temperature +40°C.
3. Sound and vibration monitoring: Frequently use a listening rod (listening stick) to listen to the internal sound of the motor and reducer, and check for abnormal noise and abnormal vibration. Stop immediately if any abnormality is found.
4. Material flow and discharge monitoring:
   • Observe whether the discharge outlet is blocked and whether feeding is uniform. Ensure that material is uniformly distributed on the belt to avoid severe offset load.
   • Check whether inlet and outlet are unobstructed and whether anything is jammed by foreign matter.
   • Check whether the discharge outlet has accumulated material and blockage, and whether discharge is smooth.
   • Check whether material adheres to the belt or pulleys and whether idlers accumulate material. Clean promptly.
5. Safety discipline:
   • During operation, it is strictly prohibited for anyone to pass through, step over, sit, lie on, or crawl under the belt.
   • It is not allowed to use the belt to transport other items.
   • It is not allowed to use sticks, shovels, etc. to remove debris from running belts or pulleys.
   • Guards for transmission parts must always remain installed.

3.3 Shutdown Operation

1. Normal shutdown: After receiving the shutdown instruction, stop feeding first (shut down upstream equipment) and stop feeding material to the belt conveyor.
   • Let the belt continue running until all material on the belt is discharged, then stop.
   • When several conveyors operate in series, shut down in sequence along the material flow direction, that is, start from the feed end and shut down progressively backward.
   • Turn off the main power, cut off the main power of the control cabinet, and hang a “Stopped / Do Not Operate” warning sign.
2. Emergency shutdown (abnormal shutdown):
   • Immediately press the emergency stop button or pull the pull cord switch to cut off power for emergency shutdown.
   • Handling after emergency shutdown: The cause of the fault must be identified and eliminated before restarting according to the startup sequence. It is strictly prohibited to force startup before the fault is eliminated. At the same time, the emergency shutdown time, cause, and handling process should be recorded in detail in the Equipment Operation Record.
3. Post-shutdown on-site handling (mandatory):
   • Clean adhered material on the belt, idlers, and pulleys.
   • Clean the surrounding environment of the equipment and keep the site tidy.
   • Check the wear condition of the belt, idlers, cleaner, etc., and prepare for maintenance or replacement if necessary.
4. Shift-change shutdown requirements:
   • Before handover, the equipment must be stopped and cleaned, and the Equipment Operation Record and Shift Handover Record must be truthfully filled in, noting the equipment operation status during the shift (key parameters such as belt deviation, temperature, and current), abnormalities, and countermeasures.
   • Before startup, incoming shift personnel must re-confirm the equipment status against the inspection requirements in the “Pre-Production Preparation Stage.”

IV. Maintenance and Care

4.1 Daily Maintenance (Each Shift)

1. Cleaning: Remove adhered material from the belt surface, idlers, and pulleys; clean dust from the frame, reducer housing, and motor surface.
2. Belt inspection: Check whether the belt deviates, is damaged (tearing, edge wear, joint cracking), or is excessively slack.
3. Idler inspection: Visually inspect whether idlers rotate flexibly, have no adhered material, and are not damaged.
4. Component inspection: Check whether the discharge outlet is blocked, whether bolts are loose, and whether the cleaner is effective.
5. Inspection record: Record operating temperature, belt status, cumulative total, etc.

4.2 Regular Maintenance

1. Lubrication maintenance cycle:
   • Regularly lubricate support rollers, thrust rollers, and transmission gears.
   • The injected lubricating oil must be clean, and seals must be good.
   • Note: For detailed lubrication guidance, see the equipment lubrication nameplate.
2. Belt tension and deviation correction:
   • Regularly check and adjust belt tension to the specified range.
   • Check and adjust self-aligning idlers, head and tail pulley positions, or the tensioning device to ensure the belt runs centered.
3. Idler and pulley maintenance:
   • Manually rotate each idler and check whether rotation is flexible and noise-free. Replace idlers that rotate poorly, are damaged, or have abnormal noise.
   • Check the rubber lagging wear of the drive pulley and bend pulley, and remove adhered material.
4. Cleaner maintenance:
   • Check the wear condition of the head cleaner and return-strand cleaner.
   • Adjust the contact pressure between the cleaner and the belt to ensure good cleaning effect.
5. Safety device inspection:
   • Check monthly whether pull cord switches, deviation switches, and other safety devices are intact and effective.
   • Pull cord switches must be tested regularly to confirm normal action.
6. Electrical system: Check motor insulation performance every six months; inspect circuits to eliminate leakage and short-circuit hazards; check the waterproof and dustproof sealing of the motor junction box and control box.

4.3 Long-Term Shutdown Maintenance

When the equipment is out of service for more than 30 days, thoroughly clean the belt and frame, and apply anti-rust grease to exposed rotating parts. If installed outdoors, cover the motor with a rain cover. Before restarting, test the motor insulation with a megohmmeter, trial run according to the no-load trial run requirements, and feed production only after confirming normal operation.

4.4 Fault Handling Principles

1. If belt deviation, slipping, abnormal noise, excessive bearing temperature, etc. are found, stop immediately; restart only after the cause is identified and the fault is eliminated.
2. It is strictly prohibited to run equipment with faults, and strictly prohibited to perform maintenance or cleaning while the equipment is running.
3. When repairing transmission parts or replacing idlers and cleaners, cut off power and hang a “Do Not Close Switch” warning sign.

V. Common Faults and Remedies