This article discusses how to increase the output of the vertical mill from the aspects of the mill structure, scraper, hydraulic system and materials.
The Internal Structure
1.1 Wear Of Grinding Roller And Disc Liner
When the vertical mill is working, the material is ground by applying pressure from the grinding roller. After a long time of operation, the grinding roller and the grinding disc become uneven and irregular due to abrasion, the grinding efficiency decreases, and the output decreases.
In this case, the wear of the liner should be checked regularly. When the wear of the grinding roller is close to 25mm and the wear of the grinding disc is close to 10mm, the size of the grinding roller and the grinding disc can be repaired by surfacing to ensure the output.
1.2 Wear Of Retaining Ring
The height of the retaining ring determines the thickness of the material layer. When the thickness of the material layer is larger, the vibration of the mill will increase, reducing the output
Reasonable setting of the height of the retaining ring has a positive effect on increasing the output.
1.3 Wear Of Nozzle Ring
The damage of the wind guide blade will make the air volume passing through the nozzle ring not evenly distributed, and it will not be able to form a stable upward airflow, which increases the circulation volume and reduces the output.
The damaged nozzle ring must be repaired after shutdown to avoid disrupting the grinding internal circulation.
In order to reduce the accumulation and compaction of the material in the center of the grinding disc, and to improve the control of the auxiliary roller on the material layer, a scraper is added to the center of the grinding disc to smooth the material and ensure that the material is evenly ground.
Hydraulic System Pressure
Use each downtime to check the pressure of the nitrogen cylinder to ensure that the nitrogen pressure of the piston accumulator is 8bar. Insufficient pressure will cause increased vibration and frequent shutdowns; the nitrogen pressure of the bladder accumulator is 40bar, and insufficient pressure will cause lift Roll timeout, slow system response.
The requirements of vertical mills on materials are mainly manifested in grindability and particle size. The higher the hardness of the material, the longer it takes for the material to be milled into a finished product, the more cycles in the mill will be, and the greater the wear of the equipment.