15 reasons for vertical roller mill host vibration

1. Loose bolts of the mill

This phenomenon is more common, mainly because the vibration during the grinding process of the machine will lead to the loosening of the bolt, which in turn will cause the vibration to increase. Check the machine in time and tighten the bolts.

 

2. Unsound foundation

The working principle of the vertical roller mill is circular motion, and vibration will occur during normal work. If the installer does not tighten the foundation while laying the foundation, the roller mill will vibrate greatly and noise will be high. The solution is to strengthen the foundation.

 

3. Installation problems

 

During installation, the center line of the transmission part of the mainframe is not straight, and vibration will occur during the rotation. In this case, the center line should be adjusted in time.

 

4. The feed particle size is too fine or too large

 

If the feed particle size is too fine, the grinding roller and the grinding ring are easily in direct contact, causing noise and vibration, and the amount of material returned to the mill should be appropriately reduced. If the feed particle size is too large, the amount of feed back should be increased to fill the gap between the large particles to achieve crushing of the material layer.

 

5. Uneven feeding or less feeding

 

If the feeding time is too little or too little, or the feeding amount is not enough, the feeding amount of the mill is not enough, resulting in the vertical roller mill empty grinding, that is, the grinding roller directly contacts the grinding ring, causing noise and vibration. The feeding amount can be controlled by adjusting the vibrating feeder to avoid empty load operation as much as possible.

 

6. Insufficient feed pressure, no continuous feed

 

The vertical roller mill not only has certain requirements for the feed particle size, but also requires continuous feeding and maintains a certain feed pressure. To ensure this, a flow stabilizing device can be added to the mill.

 

7. Excellent materials

 

Vertical roller mill has a strict limit on the hardness of the material. Exceeding its working range will cause a drop in output, severe vibration of the host, and excessive stone powder. Therefore, the hardness of the material must be well controlled.

 

8. Blockage of materials in the volute

 

Some materials are too wet and tend to stick together at the damper, resulting in poor air intake and vibration. We should remove the blocking material inside.

 

9. Deformation of grinding roller

 

Long-term wear causes the shape of the grinding roller to change, the grinding roller is not smooth, and collides with the grinding ring during rolling to cause violent vibration. The grinding roller should be replaced in time.

 

10. Analysis machine blade imbalance

 

Check whether the blade of the analysis machine is complete. Some manufacturers install the blade without commissioning in order to save costs, resulting in vibration caused by unqualified later production.

 

11. Loose parts inside the equipment

 

The very large parts inside vertical roller mill are the plum blossom frame and the grinding roller. These two parts are connected by bolts. When the device is running, it will generate a strong airflow. If these two parts are loose, the airflow will become very unstable, and it will slowly generate vibration and cause noise.

 

12. Metal objects are mixed into the grinding chamber of the vertical roller mill

 

Because the central axis of the main machine rotates quickly, the metal objects are very hard. After being picked up by the shovel, it will collide in the grinding chamber of the main machine and cause the main machine to vibrate. The metal objects need to be cleaned.

 

It should be noted that metal objects may be brought in from the raw materials, or parts inside the vertical roller mill may fall off, such as screws or bearing balls.

 

13. Different axes of the coupling between the host and the reducer

 

The direct power of the main engine and the reducer is transmitted through the coupling. After starting and rotating, the main engine and the reducer will produce vibration and noise due to the different shafts of the two couplings. Therefore, the coaxiality of the coupling shall be calibrated before starting.

 

14. There is no gap between the main unit and the reducer coupling

 

During installation, because there is no gap between the main unit and the reducer coupling, pushing up the thrust bearing will also cause vibration of the vertical roller mill. The solution is to reset the central shaft and readjust the coupling gap.

 

15. Quality problems

 

If the quality of the vertical roller mill bearings is poor and the gap is large, it will cause the plum blossom frame to swing, which will cause vibration of the equipment.