What maintenance work does a horizontal sand mill require?

1. Daily maintenance (per shift/per day)
1. Operation status monitoring
Parameter inspection: record the grinding chamber temperature (≤80℃, special materials ≤60℃), inlet and outlet pressures (feed pressure ≤0.3MPa, discharge pressure ≤0.2MPa), motor current (not exceeding 1.1 times the rated value). If there is an abnormal fluctuation, the machine needs to be stopped for investigation.
Abnormal sound and vibration: monitor the running sound of the equipment (should be stable without sharp noise), and use a vibration meter to detect the vibration value of the bearing seat (≤0.15mm/s). If it is abnormal, it may be caused by medium stagnation or rotor imbalance.
Leakage inspection: Check whether there is material or coolant leakage in the grinding cylinder end cover, feed/discharge interface, and cooling water pipeline, and replace seals (such as O-rings, mechanical seals) in time.
2. Material and medium management
Residual cleaning: After shutdown, inject cleaning fluid (such as solvent, water) through the cleaning pump, run at no load for 5-10 minutes, clean the residual material in the grinding chamber to avoid dry blockage (especially for high viscosity or easy to solidify materials).
Medium inspection: Observe whether the grinding medium (such as zirconia beads) is damaged or has abnormal particle size (can be checked by sieve filtration). If the damage rate exceeds 5%, it needs to be replenished or replaced to avoid scratching the inner wall of the grinding chamber.
2. Regular maintenance (weekly/monthly)
1. Lubrication system maintenance
Bearing lubrication: Add the specified type of grease (such as lithium-based grease, high-temperature grease) according to the instructions. The motor bearing is replenished once every 100 hours, and the spindle bearing is checked every 200 hours. The oil level is added when it is insufficient (to avoid excessive heat dissipation).
Gearbox maintenance: Check the gearbox oil level (above the center line of the oil window) every week, and check the oil quality every month (if it is turbid or has impurities, the gear oil needs to be replaced, such as 220# industrial gear oil). When changing the oil, the old oil needs to be drained and the box needs to be flushed.
2. Inspection of key components
Mechanical seal: Check the wear of the dynamic ring and the static ring (if there are scratches or cracks, they need to be replaced), ensure that the cooling water path is unobstructed (water inlet pressure 0.1-0.2MPa), and prevent dry friction from burning the sealing surface.
Filter and filter: Clean the feed inlet filter (to prevent impurities from entering the grinding chamber) and the cooling water pipeline filter (to avoid scale clogging and affect heat dissipation). If the filter is damaged, it needs to be replaced immediately.
III. Quarterly/half-year maintenance (deep maintenance)
1. Disassembly and inspection of core components
Rotor and stator: Disassemble the grinding cylinder and measure the gap between the rotor and the stator (within ±0.05mm of the original design value, such as 1.2mm, the maximum allowable gap is 1.3mm). If it exceeds the tolerance, it needs to be repaired or replaced (excessive wear will lead to reduced grinding efficiency).
Bearing life assessment: Check the bearing clearance (measured with a feeler gauge, if it exceeds 0.1mm, it needs to be replaced), check whether there is pitting or cracks on the roller surface, and use the same model of high-precision bearings (such as SKF, NSK brands) when replacing, and apply special assembly grease.
2. Electrical system maintenance
Motor inspection: Measure the motor insulation resistance (≥5MΩ), clean the dust on the motor fan cover, and check the wear of the carbon brush (if it is a brushed motor, replace it when the carbon brush length is ≤1/3 of the original length).
Control system: Clean the dust on the surface of PLC, inverter, and touch screen, check whether the terminal is loose (especially the signal line), and test whether the emergency stop button and overload protection are sensitive.
3. Pipeline and accessory maintenance
Pipeline dredging: Use a high-pressure water gun or a special pipe cleaner to clean the scale on the inner wall of the feed pipe (especially high-solid content materials), and check whether the hose is aging and cracking (it is recommended to replace the high-pressure hose every six months).
Cooling system: clean the cooling water tank, replace the coolant (or add rust inhibitor), check whether the water pump flow is normal, and avoid material degeneration or equipment overheating due to insufficient heat dissipation.
IV. Long-term shutdown maintenance (more than 1 week)
1. Thorough cleaning: Use a special cleaning agent to circulate and clean the grinding chamber and pipeline to ensure that there is no material residue, especially for corrosive or crystallized materials, which need to be treated with a neutralizer.
2. Medium treatment: Take out the grinding medium, rinse it with clean water, dry it, and store it in categories (avoid mixing different particle sizes).
3. Component protection: Apply anti-rust oil to the exposed metal surfaces such as the motor shaft and rotor shaft, seal the inlet and outlet of the grinding cylinder (with a plastic cover + sealing film), cut off the main power supply and hang the "Shutdown Maintenance" sign.
V. Maintenance precautions
1. Safety regulations: Before maintenance, the main power supply must be cut off, the feed valve must be closed, the pipeline pressure must be released, and protective equipment (gloves, goggles, dust masks) must be worn.
2. Spare parts management: Spare seals, bearings, filters, etc. must match the equipment model (such as mechanical seals must correspond to the shaft diameter and pressure level) and be stored in a dry and ventilated place.
3. Record archiving: Establish a maintenance ledger to record each maintenance time, replacement parts, and parameter changes to facilitate tracing the cause of the failure (such as frequent damage to a bearing may be due to excessive installation coaxiality).