Artificial Rice Production Line Equipment Maintenance & Maintenance Guide

General Basic Maintenance Rules (Applicable to All Equipment on the Whole Line)

1. All food contact parts shall be cleaned with food-grade detergent. Strong acid and alkali are prohibited. Wipe dry after cleaning without residual water to avoid rust and mildew.
2. Cut off power before cleaning, overhauling and disassembling. Do not open the cover with electricity.
3. Adopt food-grade lubricating oil and grease to avoid polluting grain raw materials.
4. For long-term shutdown (more than 7 days), empty silos, screws and molds, store them after full drying, and coat screws with anti-rust oil.
5. Keep the workshop dry and ventilated with ambient humidity ≤65% to prevent short circuit of motors and electric control cabinets caused by moisture.

Special Maintenance Methods for Each Single Machine

1. Raw Material Horizontal Mixer

Daily (After Shift)

1. Empty all powder inside the tank, flush the mixing paddle and inner wall with clean water, wipe thoroughly without raw material residue.
2. Check the oil seal at both ends of the mixing shaft for powder leakage; replace the oil seal immediately if leakage occurs.
3. Clean agglomerated raw materials at the bottom discharge port to prevent blockage and fermentation.

Weekly

1. Open the bearing end caps at both ends and fill with food-grade lubricating grease.
2. Check the tightness of transmission belts; adjust if too loose, replace directly if cracked or aging.
3. Tighten all fixing bolts of the frame.

2. Core Main Machine: Twin Screw Extruder (Key Maintenance Part)

Daily Pre-Shift (10 Minutes Before Startup)

1. Check the gearbox oil level, which shall be between 1/2 and 2/3 of the scale mark; replenish the same type of gear oil if insufficient.
2. Check whether heating rings and thermocouple temperature probes are loose, and confirm normal temperature display on the temperature control instrument.
3. Check the fastening bolts of the head and mold to ensure no looseness and material leakage.
4. Jog no-load operation for 30 seconds to listen for abnormal noise and scraping sound of the screw.

After Each Shift Shutdown

1. Before shutdown, add a small amount of corn starch to clean the screw, empty residual fortified rice materials in the barrel to avoid carbonized agglomerates sticking to the screw under high temperature.
2. After the barrel temperature drops below 60°C, disassemble the mold and die head, clean solidified materials in each rice hole with steel wire brush; do not hit mold holes with hard objects to prevent deformation and irregular rice shape.
3. Simply clean the screw; pull out the screw for thorough brushing and drying for long-term shutdown.
4. Clean scattered powder at the base and feeding port of the main machine to avoid spontaneous combustion of accumulated powder.

Weekly Maintenance

1. Drain gearbox oil to check oil quality; replace gear oil immediately if it turns black or contains metal debris.
2. Check lubrication of screw thrust bearings and replenish lubricating grease.
3. Clean scale of water circulation cooling pipeline to ensure smooth barrel cooling.

Monthly In-depth Maintenance

1. Pull out the screw completely, clean carbonized burnt materials in thread gaps, check screw wear degree; replace screw sleeve if threads are severely worn.
2. Correct the fitting degree of heating rings, replace damaged thermal insulation cotton to reduce energy consumption.
3. Check carbon brush wear of main motor; replace if the carbon brush is too short, and clean dust on motor cooling fan.

3. Rotary Cutter (Rice Shaping & Cutting)

Daily

1. Clean sticky rice grains on cutter disc and blade edge, wipe dry with clean water.
2. Check blade clearance; the gap between blade and template shall be 0.1~0.3mm. Uneven rice length will appear if the gap is too large.
3. Check blades for chipping and passivation; polish or replace blades in time if passivated.

Weekly

1. Fill cutter bearings with food-grade butter.
2. Clean dust on transmission chains and apply a small amount of lubricating oil to chains.
3. Tighten fixing screws of cutter disc to prevent loosening during high-speed rotation.

4. Multi-layer Mesh Belt Dryer

Daily After Shift

1. Open the dryer door, clean broken rice and burnt particles on the mesh belt, and sweep residues in mesh belt gaps with a brush.
2. Clean dust adhered to circulating hot air fan blades to avoid insufficient air volume and uneven drying.
3. Clean agglomerated dust in moisture exhaust duct to prevent exhaust blockage and internal moisture reversion.

Weekly

1. Check mesh belt tightness, adjust deviation rollers on both sides if the belt deviates; replace the mesh belt in time if damaged or broken.
2. Remove dust on heating pipes/heat conduction oil pipelines; accumulated dust will reduce heating efficiency and increase power consumption.
3. Fill fan bearings with lubricating grease.

Monthly

5. Nutrition Coating Machine (Vitamin & Oil Spraying)

Daily

1. Empty material tank and spraying pipeline, flush oil nozzles with warm water to avoid nozzle blockage caused by oil solidification.
2. Wipe the inner wall of mixing tank without oil agglomerates.
3. Clean sticky rice grains on conveying rollers.

Weekly

1. Clean internal pipelines of spraying pump and dredge tiny nozzles.
2. Fill roller bearings with lubricating grease.

6. Cooling Conveyor & Elevator

7. Automatic Packaging Machine

Daily

1. Clean starch and rice crumbs in feeding hopper, remove residual powder on sealing wheels.
2. Check sealing heating wire; replace immediately if blackened or broken.

Weekly

1. Lubricate film rollers and transmission chains, clean dust on photoelectric sensors (dust will cause inaccurate fixed length).
2. Tighten fixing screws of weighing sensors to ensure metering accuracy.

Standard Maintenance Schedule by Cycle

1. Daily Maintenance (5 mins before shift + 15 mins after shift)

2. Weekly Maintenance (Half-day Shutdown)

3. Monthly Maintenance (1-day Shutdown)

4. Annual Overhaul (Once a Year, 72 Hours Shutdown)

1. Replace all gear oil of extruder gearbox;
2. Detect wear of screws and bushings, replace if wear exceeds standard;
3. Replace all aging oil seals, gaskets and heating rings;
4. Disassemble and maintain motors and fans, replace bearings;
5. Derust and repaint the whole machine, replace aging electric control lines;
6. Conduct 4-hour no-load trial run of the whole machine, calibrate temperature, speed and metering parameters.

Replacement Cycle of Vulnerable Parts (For Overseas Customers Reference)

1. Extruder screw & sleeve: 8000~12000 production hours
2. Cutting blades: 15~30 days (depends on raw material hardness)
3. Forming mold: 6~12 months
4. Dryer mesh belt: 1~2 years
5. Various oil seals and gaskets: 3~6 months
6. Heating rings and thermocouples: 6~10 months
7. Packaging machine sealing heating wire: 1~3 months

Maintenance of Electric Control System (Critical)

1. Daily: Check normal operation of electric control cabinet fan, no peculiar smell or abnormal noise.
2. Weekly: Blow off dust inside the cabinet with dry air gun after power cut; dust easily causes short circuit.
3. Monthly: Check whether wire terminals are loose and overheated, wrap damaged cable skins in time.
4. Rainy/humid areas: Place desiccant in electric control cabinet to prevent PLC and frequency converter burning due to moisture.
5. Do not flush electric control boxes and motors directly with water; only clean with dry brushes.

Storage Maintenance for Long-term Shutdown (Off-season for Overseas Clients)

1. Empty all raw materials of the whole line, wash and dry all food contact surfaces completely;
2. Clean and dry screws and molds, coat with food-grade anti-rust oil and store separately in sealed packages;
3. Fill sufficient lubricating grease on all bearings and chains;
4. Wrap motors and electric control cabinets with waterproof plastic film;
5. Close total water, gas and power supply;
6. Keep the workshop ventilated, run no-load for 10 minutes every 15 days to prevent rust and jamming.

Key Maintenance Points to Prevent Common Faults

1. Frequent mold hole blockage: Clean the mold every day, sieve raw materials to remove large impurities;
2. Slow temperature rise of main machine: Regularly remove dust on heating rings, replace damaged thermal insulation cotton;
3. Uneven dryness and wetness of rice grains: Clean drying air ducts and fans weekly to ensure circulating hot air;
4. Belt slipping and abnormal noise: Adjust belt tension weekly and replace aging belts in time;
5. Inaccurate metering (packaging machine): Clean photoelectric head weekly, calibrate weighing sensors monthly.