What are the diagnosis and treatment methods of common flotation machine failures

As a crucial equipment in the mineral processing process, the operating status of the flotation machine directly affects the ore recovery rate and concentrate quality. In the long-term operation process, the flotation machine will inevitably have various faults. Mastering the diagnosis and treatment methods of common flotation machine faults can not only ensure stable production operation, but also extend the service life of the equipment and reduce maintenance costs.

Bearing overheating or damage
Fault manifestations:
The bearing temperature rises, abnormal noise occurs, and even jamming and bearing rupture occur.
Cause analysis:
Insufficient lubricating oil or poor oil quality;
Failure of bearing seal leads to dust or water ingress;
Improper bearing installation or improper bearing clearance adjustment;
Long-term overload operation leads to bearing fatigue.
Treatment method:
Check the lubrication system to ensure that the oil volume is sufficient and the oil quality meets the requirements;
Regularly replace the grease and use high temperature and high load grease;
Replace the damaged bearing and adjust the installation fit accuracy;
Strengthen the sealing structure of the bearing position to prevent water and dust from intruding.

Severe wear of the impeller or stator
Fault manifestations:
The stirring effect is weakened, the bubble distribution is uneven, and the flotation effect is reduced.
Cause analysis:
Long-term high-concentration slurry operation causes impeller wear;
Use of non-wear-resistant materials causes stator surface damage;
Debris enters the flotation tank, causing mechanical damage.
Treatment method:
Use wear-resistant materials (such as high chromium alloy or polyurethane) to manufacture impellers and stators;
Regularly check the wear of impellers and stators and replace them in time;
Add a pre-treatment screening system to prevent large particles or foreign matter from entering.

Insufficient gas volume or unstable airflow
Fault manifestation:
The amount of bubbles is reduced, the foam layer is uneven, the minerals are difficult to adhere or the foam breaks quickly.
Cause analysis:
Air pipeline blockage;
Abnormal operation of air compressor or blower;
The gas distributor (sparger) is blocked by slurry or reagents;
The regulating valve fails, resulting in the inability to adjust the airflow.
Treatment method:
Clean the gas system to ensure that the pipeline is unobstructed;
Repair or replace the blower and air pressure system components;
Regularly disassemble and inspect the gas distributor, and flush it with high-pressure water or compressed air;
Replace the failed regulating valve or add an automatic control device.

The foam layer is unstable or overflow is abnormal
Fault manifestation:
The foam layer is too thick, too thin or intermittent, and the foam overflow changes frequently.
Cause analysis:
Uneven reagent addition or improper dosage control;
Stirring speed is too fast or too slow;
Slurry concentration fluctuates greatly;
The foam scraper installation angle is not suitable.
Treatment method:
Use automatic reagent addition system to improve addition accuracy;
Adjust stirring speed to maintain reasonable turbulence state;
Stabilize slurry concentration through thickener or ore feeding and slurry mixing system;
Adjust the foam scraper angle to optimize the scraping effect.

The motor is abnormal or cannot start
Fault manifestation:
The motor cannot start, trips during operation or serious vibration occurs.
Cause analysis:
Motor overload or insulation aging;
Unstable power supply voltage;
Coupling misalignment causes partial load;
Poor line contact or control system failure.
Treatment method:
Check and replace the motor insulation system to avoid short circuit;
Install a voltage stabilizer to ensure that the voltage fluctuation is within the allowable range;
Adjust the centering accuracy of the coupling to reduce mechanical stress;
Replace the control box components and clean the circuit contacts.

The foam scraper is not running smoothly
Fault manifestation:
The foam scraper is stuck, the operation is offset, and the foam remains in the tank.
Cause analysis:
The mechanical transmission parts are rusted or lubricated poorly;
The scraper guide rails are seriously worn;
The motor control system fails or the limit switch fails.
Treatment method:
Clean the lubrication parts and add grease;
Replace the worn guide rails or pulleys;
Inspect the electric control circuit and correct the scraper running track;
Install an automatic deviation correction system to improve stability.

The slurry in the flotation tank is churning or short-circuited
Fault manifestation:
The slurry liquid level is unstable, the minerals cannot be effectively stratified and sorted, and the flotation index fluctuates.
Cause analysis:
Excessive or discontinuous feeding of ore;
Irrational design of the flotation tank and disordered tank body partitioning;
The bubbles are too large, disrupting the slurry flow field.
Treatment method:
Adjust the feeding system to stabilize the feed flow rate;
Optimize the flotation tank design, add baffles or slurry mixing devices;
Finely adjust the gas flow rate and reagent type to generate uniform and fine bubbles.