Internal Rotary Drum Filter

Common faults and treatment methods

Screen clogging and breakage

Screen clogging

Cause: high concentration of suspended solids or insufficient backwashing frequency, resulting in the accumulation of impurities on the surface of the screen;

Manifestations: decreased water production, increased liquid level in the drum chamber, abnormal backwashing frequency;

Treatment: increase the intensity of backwashing (it is recommended to use a word high-pressure nozzle), check the pressure of the backwash water source (≥ 0.3MPa), chemical cleaning of the filter.

Filter screen breakage

Cause: long-term mechanical wear, sharp foreign objects impact or backwashing pressure is too high;

Performance: the suspended solids content of the effluent water rises, the water quality is turbid;

Treatment: stop to replace the screen (aperture 0.2mm), check whether the inner wall of the drum residual sharp objects.

Insufficient backwashing strength

Reason: nozzle clogging, pump failure or improper parameter settings;

Treatment: clean up the nozzle impurities, check the pump operating status, adjust the backwashing time Interval.

Sensor failure

Cause: Water level/clogging sensor covered by impurities or aging components;

Treatment: Clean the sensor surface, calibrate periodically or replace the damaged sensor. Treatment: Clean the sensor surface, calibrate periodically or replace damaged sensors.

Insufficient water/air pressure

Cause: Fluctuation of water supply pressure or leakage of air pipeline;

Treatment: Install pressure stabilizer and check the sealing of pipeline.

 Abnormal drive unit

Motor overheating or strange noise

Cause: excessive drum load (e.g., screen is seriously clogged) or insufficient bearing lubrication;

Treatment: stop the machine immediately to check the screen clogging, replenish the grease or replace the bearing.

Chain/gear loosening

Reason: Long-term vibration leads to the displacement of transmission parts;

Treatment: Adjust the chain tightness every month, replace the worn gear.

Abnormal water quality

Suspended solids drop (<80%)

Cause: screen clogged, broken or overloaded inlet water flow;

Treatment: reduce the inlet water flow, clean or replace the screen, check the operation status of the slag-guiding screw.

Turbid or fibrous water

Cause: impurity leakage due to aging of sealing strip or deformation of filter screen;

Treatment: replace the sealing parts of drum end cover and correct the flatness of filter screen.

Troubleshooting process

Stop the car and check: close the water inlet valve and empty the water inside the drum to avoid secondary pollution;

Targeted maintenance: choose to clean, replace or debug the parts according to the fault performance (e.g., prioritize the clogging problem);

Trial run verification: monitor water quality, current and noise after restarting the equipment to ensure troubleshooting.

Through regular maintenance (such as quarterly filter inspection, monthly lubrication of drive components) can significantly reduce the failure rate.