Daily maintenance of industrial multi temperature zone rotary furnace

As a key equipment for high-temperature and continuous operation, the daily maintenance of industrial multi zone rotary furnaces needs to revolve around four core modules: mechanical structure, heating system, control system, and safety protection. Systematic maintenance can significantly reduce failure rates, extend equipment lifespan, and ensure process stability. The following is a specific maintenance plan:

1. Mechanical structure maintenance
a. Furnace body and supporting wheel system
Daily inspection:
Check the levelness of the furnace body daily (using a laser level), ensuring that the tilt angle is within the range of 1 ° -5 °, to avoid material accumulation or abnormal transmission caused by excessive tilt.
Monitor the temperature of the supporting wheel bearing using an infrared thermometer. The normal value should be ≤ 65 ℃. If the temperature exceeds the limit, check the condition of the lubricating oil or the clearance between the bearings.
Regular maintenance:
Every 3 months: Adjust the position of the supporting wheel to ensure that the axial displacement of the furnace body is ≤ 5mm, to prevent furnace tube wear caused by axial displacement.
Every 6 months: Replace the lubricating oil of the idler bearing (using high-temperature resistant lithium grease), clean the oil stains, and check the integrity of the sealing ring.
b. Transmission system
Daily inspection:
Monitor the motor current (ammeter), and the normal value should be stable at 80% -90% of the rated current. If the fluctuation exceeds 10%, check the gear meshing or coupling status.
Check the oil level (dipstick) of the gearbox, which should be between the upper and lower limits. If the oil is cloudy, it needs to be replaced immediately.
Regular maintenance:
Every month: tighten the bolts of the transmission base to prevent loosening due to vibration.
Every 12 months: Disassemble and inspect the wear of the gears. If the pitting area on the tooth surface exceeds 30%, the gears need to be replaced.
c. Furnace tube sealing
Daily inspection:
Observe whether there is any material leakage or air leakage at the sealing point of the kiln head/tail (using smoke testing method), and the air leakage rate should be ≤ 3%.
Check the compression force (pressure gauge) of the fish scale seal or cylinder compression seal, and the normal value should be maintained at 0.2-0.5MPa.
Regular maintenance:
Every 3 months: Replace worn fish scales or adjust cylinder stroke to ensure a sealing gap of ≤ 1mm.
Every 6 months: Clean the accumulated material in the sealing chamber to prevent particle jamming and seal failure.

2. Heating system maintenance
a. Electric heating element
Daily inspection:
Use an infrared thermometer to monitor the surface temperature of the electric heating element. The temperature difference between the elements in the same temperature zone should be ≤ 20 ℃. If it exceeds the tolerance, check the contact resistance or aging of the elements.
Observe the color change of the component, which is normally dark red. If there is local whitening or breakage, it should be replaced immediately.
Regular maintenance:
Every 6 months: Tighten the wiring terminals of the electric heating element to prevent an increase in contact resistance due to looseness (contact resistance should be ≤ 0.1 Ω).
Every 12 months: Replace aging components (usually with a lifespan of 8000-12000 hours), and record the location of the components during replacement to avoid uneven power distribution.
b. Insulation layer
Daily inspection:
Observe whether there are cracks or peeling on the surface of the insulation layer, especially paying attention to the joints of the furnace body.
Use a thermal imaging device to detect the surface temperature of the furnace body. The normal value should be ≤ ambient temperature+50 ℃. If the temperature exceeds the limit, check the thickness or integrity of the insulation layer.
Regular maintenance:
Every 24 months: Replace severely damaged insulation layers (such as aluminum silicate fiber boards), compact and secure them after replacement.

3. Control system maintenance
a. PLC/DCS system
Daily inspection:
Monitor the operating status of the system (HMI interface) to ensure there are no alarm messages (such as temperature exceeding limits, communication interruption).
Check the historical data recording function to confirm the data storage period (usually ≥ 30 days) and integrity.
Regular maintenance:
Every 3 months: Backup system programs and parameters to prevent data loss due to unexpected power outages.
Every 12 months: Upgrade system software, fix known vulnerabilities, and optimize control algorithms.
b. Sensors and Instruments
Daily inspection:
Verify the accuracy of the temperature sensor (thermocouple/thermistor), compare it with a standard source, and the error should be ≤ ± 1 ℃.
Check the zero drift of the pressure transmitter, the normal value should be ≤± 0.5% FS.
Regular maintenance:
Every 6 months: Replace aging sensors (usually with a lifespan of 3-5 years), and perform linear calibration after replacement.
Every 12 months: Clean the dust on the sensor probe to prevent measurement errors.
c. Electrical cabinet
Daily inspection:
Monitor the temperature of the electrical cabinet (temperature and humidity meter), and the normal value should be ≤ 40 ℃. If the temperature exceeds the limit, check the status of the cooling fan.
Check the tightness of the wiring terminals to prevent sparking or poor contact caused by looseness.
Regular maintenance:
Every 3 months: Clean the dust inside the electrical cabinet using a vacuum cleaner or compressed air (pressure ≤ 0.2MPa).
Every 12 months: Check the wear of circuit breaker and contactor contacts, and replace them if the contact erosion area exceeds 50%.

4. Security protection maintenance
a. Emergency shutdown system
Daily inspection:
Test the function of the emergency stop button to ensure that the equipment can stop running within 5 seconds after being pressed.
Check the safety interlock device (such as over temperature and over pressure interlock), simulate fault signals to verify the reliability of the action.
Regular maintenance:
Every 6 months: Replace the emergency shutdown system battery (such as UPS) to ensure that the system can maintain operation for at least 15 minutes after a power outage.
b. Fire protection system
Daily inspection:
Check the pressure of the fire extinguisher (pressure gauge). The green area is normal, the yellow area needs to be filled, and the red area needs to be replaced.
Test the sensitivity of the fire alarm device and verify the alarm response time (should be ≤ 30 seconds) using a smoke generator.
Regular maintenance:
Every 12 months: Replace expired fire extinguishers (usually valid for 5 years) and update the fire equipment ledger.
c. Personal protective equipment
Daily inspection:
Confirm that the operators are equipped with heat-resistant gloves, protective face shields, and dust masks, and that the equipment is undamaged.
Check emergency lighting and escape route signs to ensure they are clearly visible.
Regular maintenance:
Every 6 months: replace aging protective equipment, organize safety training, and assess the emergency response capabilities of operators.

5. Maintain records and optimize
Establish a maintenance ledger: record the maintenance time, content, replacement parts, and responsible person for each maintenance, and form a traceable maintenance file.
Data analysis and optimization: By calculating the frequency of equipment failures (such as the average number of failures per month) and maintenance costs, identify high-frequency failure points and optimize maintenance strategies (such as shifting from regular maintenance to predictive maintenance).
Spare parts management: Reserve key spare parts (such as electric heating elements, bearings, sensors) to ensure that the inventory can meet the production needs for 3 months, while avoiding excessive reserves that may lead to capital occupation.