After long-term operation in dusty environments such as wood processing plants, mines, and construction sites, a large amount of dust will accumulate inside the hot air blower, leading to poor heat dissipation, electrical short circuits, motor overload, and even fire risks. To ensure the performance and safety of the equipment, systematic cleaning should be carried out regularly. The following provides professional and operational solutions from three aspects: pre-cleaning preparation, core component cleaning, and deep maintenance and inspection.
First, preparations before cleaning
Safety protection
Power-off operation
Turn off the power and unplug the plug. Hang a “Do Not Close the Switch” warning sign to prevent electric shock.
Wait for the equipment to cool down completely (≥30 minutes) to avoid scalding from high temperatures.
Protective equipment
Wear a dust mask (N95 or above), goggles and dust gloves to prevent dust from being inhaled or coming into contact with the skin.
Second, the cleaning steps for core components
1. External cleaning
Step:
Use a vacuum cleaner to remove the floating dust on the surface of the shell, with a focus on cleaning the air inlet, air outlet and heat dissipation holes.
Wipe the outer shell with a damp cloth (slightly damp, avoid dripping water). For stubborn stains, you can dip a small amount of neutral detergent.
After drying, check whether the sealing strip of the shell is aged and replace it if necessary.
2. Internal air ducts and heat dissipation system
Heat sink cleaning
Use compressed air to blow in reverse from the gap of the heat sink to remove the embedded dust (such as cotton fluff, wood chips).
If the dust accumulation is severe, remove the heat sink and rinse it with a soft brush and a low-pressure water gun (≤0.3MPa). After drying, reinstall it.
Air duct cleaning
Disassemble the connecting pipe of the air duct, use a vacuum cleaner to remove the accumulated dust inside, and then wipe the inner wall with a soft cloth.
Check the sealing performance of the air duct and repair the damaged or fallen sealing strips.
3. Cleaning of fans and motors
Fan blade
Use a soft-bristled brush to remove the dust on the surface of the blades. Avoid scraping with hard objects to prevent the dynamic balance from being disrupted.
Case: A certain factory suffered a motor overload and burnout due to failure to clean the dust accumulated on the fan blades, resulting in a loss of over 20,000 yuan.
Motor cleaning
Use compressed air to blow the surface of the motor and the heat dissipation holes, with a focus on cleaning the dust in the winding clearance.
If there is oil stain on the surface of the motor, wipe it with anhydrous ethanol and then apply anti-rust lubricant.
4. Electrical system cleaning
Control box
Open the control box, use a vacuum cleaner to remove the floating dust inside, and avoid touching the circuit board.
Blow the contacts of relays and contactors with compressed air to remove the oxide layer.
Circuit board cleaning
Gently remove the dust on the surface of the circuit board with an anti-static brush, or wipe it with an anhydrous ethanol cotton swab (alcohol spray is prohibited).
Check if the terminal blocks are loose. The tightening torque should comply with the manufacturer’s standards (for example, for M4 bolts, 1.2 to 1.5N·m is required).
5. Filter screens and sensors
Filter screen cleaning
Remove the air inlet filter screen, rinse it with clean water and let it dry, or use a vacuum cleaner to remove the surface dust.
When the filter screen damage rate exceeds 30%, it needs to be replaced (for example, the cost of HEPA filter screens is about 50 to 100 yuan per piece).
Sensor cleaning
Clean the surface of the temperature sensor and wind speed sensor with a cotton swab dipped in anhydrous ethanol to avoid blocking the sensing holes.
Third, in-depth maintenance and inspection
1. Performance testing
Step:
After cleaning, run the fan unloaded for 10 minutes and observe the changes in fan speed, noise and temperature.
When using an infrared thermometer to measure the temperature of the motor casing, it should be ≤70℃ (when the ambient temperature is 30℃).
Check the air velocity at the air outlet, which should be ≥ 90% of the rated value (for example, the rated air velocity is 5m/s, and the actual air velocity is ≥4.5m/s).
2. Insulation testing
Tool: 500V megohmmeter.
Standard:
The insulation resistance between the motor winding and the casing is ≥1MΩ (≥0.5MΩ in a humid environment).
If the resistance value is too low, the motor needs to be disassembled for further cleaning or drying.
3. Lubrication maintenance
Bearing lubrication
Use a grease gun to replenish high-temperature resistant grease (such as lithium-based grease) to the bearings, with each replenishment amounting to 1/3 to 1/2 of the free space of the bearings.
Case: A certain hot air blower got stuck due to a lack of oil in its bearing, and the repair cost exceeded 3,000 yuan.
Fourth, Precautions
Prohibited behavior:
It is strictly prohibited to directly rinse the motor or control box with a high-pressure water gun.
It is prohibited to clean plastic parts with corrosive solvents such as gasoline and banana water.
Professional disassembly
If it is necessary to disassemble the motor or circuit board, it is recommended to have it done by professionals to avoid damaging the components.
Record Management
Establish a “Hot Air Blower Cleaning and Maintenance Record Form” to record the cleaning time, component status and replaced parts.
Fifth, Summary
The cleaning of the hot air blower after its use in a dusty environment should follow the principle of “cut off the power first, then remove the dust, and finally conduct the inspection”. Through scientific cleaning, the failure rate can be reduced by more than 60%, and the service life of the equipment can be extended by 2 to 3 times. If any abnormalities still exist after cleaning (such as motor overheating or insufficient wind speed), the machine should be stopped immediately and professional personnel should be contacted for inspection and repair to avoid potential safety hazards.
