The thickener is mainly used for the dehydration of concentrate and tailings in the concentrator. In daily application, the pressing rake is one of the common faults of the thickening machine. Once the rake is pressed, it will not only waste a lot of manpower and material resources but also stop work in severe cases. Production stops, resulting in higher investment costs. Therefore, it is necessary to find faults and solve them in time and prevent them effectively.

The concentrator itself causes the rake to be pressed

The failures of the thickener itself mainly include the falling off of the rake teeth, the deformation of the rake, the falling off of the angle steel agitator, and the failure of the underflow pump.

1. The rake teeth of the thickener rake fall off

The material of the thickener is scraped from the upper part of the thickener to the bottom during the transmission of the rake. If the rake (part of the rake) of the thickener rake is damaged or falls off, the material cannot be effectively scraped off during the rotation of the rake, so that If the material accumulates, it is prone to the failure of the rake.

2. Deformation of the thickener rake

The deformation of the rake of the thickener is similar to the falling off of the rake teeth. When the rake is bent and deformed, the rake teeth at the deformed position during the transmission process cannot scrape off the material stably and effectively. If this happens for a long time, the material will accumulate and cause the rake to be pressed.

3. The angle steel stirrer of the thickener falls off

There is a ring-shaped trough at the bottom of the material accumulation of the thickener. During the transmission of the rake, the angle steel agitator at the bottom of the rake is also continuously stirring, which mainly plays the role of loosening the material, so that the material can be output normally with the underflow pump. If the angle steel agitator falls off, and the bottom material cannot be output normally, there will be a pressure rake failure.

4. Failure of the underflow pump of the thickener

Under normal circumstances, the thickener is not allowed to lift the rake, only in individual cases, it is allowed to lift the rake briefly. For example, when the underflow pump of the thickener fails for a short time (a fault that can be quickly solved), the rake can be temporarily lifted a little without stopping the feeding, and the rake can be gradually lowered to a low point after the sixth pump failure is solved.

The solution to the above problems: The operator must make inspection records in strict accordance with the daily inspection and maintenance requirements. Usually, the operation of the equipment should be observed at any time, and if it is found that the operation is not normal, the fault should be checked and solved in time. Remember, it cannot be forced to run for production if the thickener fails.

Improper feeding of thickener causes raking

There are two main reasons for the pressure rake caused by improper feeding of the thickener, one is that the feeding amount is greater than the processing capacity, and the other is that the feeding is too coarse.

1. The feed volume of the concentrator is greater than the processing volume

When the feeding amount of the thickener is greater than the processing capacity for a long time, the underflow is in the discharge of ore, which will increase the torque. Once the torque is so high that the rake is automatically lifted (a thickener that can automatically lift the rake), there will be a pressure rake failure.

Solution: It should be ensured that the feeding amount is consistent with the processing amount. In the follow-up, once the torque is high, the feeding amount should be reduced, and the bottom flow should be appropriately increased. After the normal time is restored, the feeding and bottom flow should be adjusted to the normal state.

2. The feed particle size of the thickener is too coarse

The feed particle size of the thickener is too coarse mainly because the particle size in the grinding operation does not meet the requirements. The particle size of the pulp material in the thickener is too coarse, and the sedimentation in the thickener will be too fast and compact, and it is not easy to be scraped off by the rake, and the material that is too coarse is easy to cause wear on the rake. At the same time, the underflow pump of the thickener is prone to segregation when conveying coarse-grained materials (that is, the water will be washed away, and the coarse sand will be left behind).

Solution: The grinding capacity should be reduced in time, or the feeding of the thickener should be stopped. On the other hand, the grinding workshop should be strictly required to control the grinding particle size.

Above, we only described the reasons and solutions of the thickener pressing rake from the two dimensions of equipment failure and improper feeding. In addition, the rationality of the design of the thickener and the proper operation of the staff may also cause the thickener to press the rake. Therefore, in actual production, the maintenance personnel should pay attention to the maintenance, maintenance, and cleaning of the thickener, and require the maintenance personnel to master the equipment principle and fault maintenance characteristics, carry out reasonable maintenance and prolong the service life of the thickener.