How to determine if the cooling fan of FAF67-4.21-4KW reducer is running normally

To determine whether the cooling fan of FAF67-4.21-4KW reducer is operating normally, it is necessary to combine mechanical characteristics and multidimensional detection methods. The specific steps are as follows:
1、 Basic observation and auditory detection

Observation of operating status

After starting the gearbox, directly observe whether the fan blades are rotating at a constant speed (speed fluctuation should be<5%). If there is jamming, stopping or obvious shaking, there is a fault.

By observing the airflow disturbance through the radiator grille, continuous airflow output should be felt during normal operation.

Abnormal noise recognition

During normal operation, the fan noise should be stable (usually<65dB). If there are metal friction sounds, periodic "clicking" sounds, or high-frequency whistling sounds, it may be due to bearing wear or blade deformation.

2、 Temperature and performance verification

Temperature difference detection of radiator

After running for 1 hour, measure the temperature difference between the upper and lower parts of the radiator with an infrared thermometer. The normal value should be ≥ 8 ℃ (when the ambient temperature is 25 ℃). If the temperature difference is less than 3 ℃, it indicates that the fan is not effectively dissipating heat.

Temperature rise monitoring

During continuous operation, the temperature of the gearbox casing should remain stable within the range of 50-60 ℃. If the oil temperature exceeds 70 ℃ and the fan does not start, check the temperature control switch or circuit.

3、 Electrical and mechanical component inspection

Circuit testing

Use a multimeter to measure the voltage of the fan motor (usually 24V/220V). If the deviation exceeds ± 10%, check the power supply or circuit.

Check fuses and relays, melting or poor contact can cause power interruption.

Mechanical condition assessment

After manually turning off the power, the blades should rotate flexibly without any jamming. If the resistance is too high or the axial shaking exceeds 0.5mm, the bearing needs to be replaced.

Check whether the blades are deformed (radial runout>1mm) or have accumulated dust, which affects the air output.

4、 Auxiliary diagnostic tool

Vibration analysis: Use a vibration meter to detect the fan bracket, and the normal vibration value should be<4.5mm/s. Abnormal vibration may indicate bearing wear or loose installation.

Thermal imaging scanning: locate local overheating areas, such as abnormal temperature rise (>80 ℃) in motor windings or bearing parts, indicating internal faults.

Maintenance suggestion: Regularly clean the fan blades and cooling channels, replenish lubricating grease every 2000 hours (recommended to use high-temperature resistant lithium grease), and record operating data to establish a health baseline.