Some concentrators did not adjust the size of the opening of the classifier during the equipment installation, and the operator did not pay attention to it during the vertical roller mill operation.

which would also affect the grinding operation invisibly. The lower opening of the classifier is low, and the ore sedimentation area is large, so the amount of returned sand is increased, and the fineness of grinding is relatively fine.

The lower opening of the classifier is large, the ore sedimentation area is large, and the water flow is relatively smooth, so the amount of returned sand is increased, and the fineness of grinding is relatively fine. In the same way, when the opening on the classifier is low and large, the amount of returned sand will increase and the fineness of grinding will be relatively finer. Otherwise, on the contrary, the grinding fineness becomes coarser.

1. Vertical Roller Mill Does Not Produce Powder Or Less

The causes are as follows: 1) the discharge valve (powder locking device) is not closed tightly, and the outside air and dust are sucked back; 2) The air duct of the main engine is blocked; 3) Blade wear, resulting in too little or unable to shovel material; 4) There is serious air leakage at the joint of pipe and flange.

Solutions: 1) repair or seal the discharge valve; 2) Remove the blockage; 3) Check the blade wear and replace it; 4) Carefully check and re seal the air leakage.

2. The oil tank and transmission are hot

Causes: 1) the viscosity of engine oil is too thick; 2) The direction of the analyzer is not right.

Solutions: 1) check whether the viscosity of engine oil meets the requirements; 2) Adjust the running direction of the analyzer.

 

Periodically inspect the oil quality and detect the content of metal particles in the oil sample to determine the bearing damage. At the same time, keep the lubricating oil clean, and judge whether to replace the lubricating oil according to the oil quality and the replacement interval of the oil filter.

Pay attention to the heating and cooling operation of the mill. Most manufacturers do not pay attention to the heating and cooling operations of ultrafine vertical mills, and fail to realize that reasonable heating and cooling operations can prolong the service life of key large bearings and wear parts.

Reasonable heating rate can heat the roller sleeve, liner plate and bearing uniformly, thereby prolonging the service life of the liner plate, roller sleeve and key bearing. Among the spare parts of the mill, the price of these key parts is relatively expensive, and any one of them is damaged. Will directly affect the operation cycle of the mill.

Due to the importance of the roller lubrication system to the bearing of the vertical mill, a simple method can be used to quickly diagnose whether the roller bearing is faulty in normal production:

One is to observe the oil condition in the grinding roll on site, or to determine whether the bearing of the grinding roll is damaged by detecting the content of metal particles in the oil sample. If the content of metal particles in the oil sample is high, the bearing has been seriously damaged.

The second is to observe the oil return temperature of the ultrafine vertical mill. If the oil return temperature of a certain ultrafine vertical mill rises and the return oil temperature of other ultrafine vertical mills is normal, it indicates that the bearing of the ultrafine vertical mill is damaged.

Metal objects are mixed into the grinding chamber of the main engine of ultrafine vertical mill

Since the central axis of the main machine rotates very fast and the metal objects are very hard, after being shoveled up by the shovel, they will collide everywhere in the main machine's grinding chamber, causing the main machine to vibrate, and the metal objects need to be cleaned.

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

The couplings of the main engine and the reducer are different

The direct power of the main engine and the reducer is transmitted through the coupling. After the machine is turned on, the main machine and the reducer will produce vibration and noise because the two couplings have different shafts. Therefore, the coupling must be calibrated before starting the machine.