Lubrication and maintenance of the fan motor of the hot air blower is a key measure to ensure the smooth operation of the motor, reduce noise and extend its service life. Improper lubrication can lead to bearing wear, motor overheating and even jamming. The following systematically expounds the maintenance methods from aspects such as lubrication cycle, lubricant selection, operation steps and precautions.
First, lubrication cycle and standards
Suggested lubrication cycle
In normal environment: Lubricate once every six months or after 1,000 hours of operation.
High-dust/high-temperature environment: Lubricate once every 3 months or after 500 hours of operation.
New motor: Grease needs to be replenished after the first 200 hours of operation (wear is fast during the running-in period).
Lubrication quantity control
Bearing capacity: Each time, add grease to 1/3 to 1/2 of the free space of the bearing (too much will cause leakage, and too little will result in insufficient lubrication).
If the inner cavity volume of the bearing is 10cm³, then 3 to 5cm³ of grease should be replenished each time.
Second, lubricant selection
Type matching
High-temperature environment: Select high-temperature resistant lubricating grease (such as lithium-based grease, composite aluminum-based grease, with a dropping point of ≥200℃).
High-speed motor: Use low-viscosity grease (such as NLGI No. 2) to reduce stirring resistance.
Rust prevention requirements: Lubricating grease with rust prevention additives added (such as compound grease containing molybdenum disulfide).
Avoid mixed use
Lubricating greases of different brands or models may undergo chemical reactions, leading to a decline in performance.
Case: After a certain factory mixed lithium-based grease and calcium-based grease, the temperature of the bearings rose by 15℃, and the grease hardened and failed.
Third, lubrication operation steps
Preparatory work
Shutdown and power cut-off: Ensure that the hot air blower has completely stopped and the power supply is cut off. Hang a warning sign reading “Do Not Close the Switch”.
Clean the environment: Use compressed air to blow off the dust on the surface of the motor to prevent impurities from entering the bearings.
Lubrication implementation
Method One: Add with a fat injection gun
Locate the bearing oil injection hole (usually at the motor end cover).
Connect the grease injection gun and slowly add the grease until the old grease is discharged from the oil drain hole (indicating that the new grease has been filled in place).
Method Two: Disassemble the bearing lubrication (applicable to motors without oil injection holes)
Remove the motor end cover and take out the bearing.
Clean the bearings with kerosene to remove old grease and impurities.
Manually apply grease to the raceways and roller surfaces of the bearings, reinstall the bearings and install the end covers.
Run the test
After lubrication, manually rotate the motor shaft to confirm that it rotates smoothly without any jamming.
Run it without load for 10 minutes and observe whether the temperature and noise are normal.
Fourth, safety precautions
Protective equipment: Wear goggles and gloves during operation to prevent grease from splashing into the eyes or skin.
Waste grease treatment: Old lubricating grease is an industrial waste and should be collected in accordance with environmental protection requirements and handed over to professional institutions for treatment.
Professional training: Non-professionals are prohibited from disassembling the motor to avoid electric shock or mechanical injury.
Fifth, Summary
The lubrication and maintenance of the fan motor of the hot air blower should follow the principles of “reasonable cycle, precise grease selection, and standardized operation”. Through scientific lubrication, the wear rate of bearings can be reduced by more than 50%, and the service life of the motor can be extended by 2 to 3 times. In case of complex problems (such as persistent abnormal noises from bearings), the machine should be stopped immediately and professional personnel should be contacted for maintenance to prevent the fault from expanding.
