What factors affect the grinding of roller mill / vertical mill?
Posttime£º2017-10-20 14:25:45 Read£º693
Vertical mill / roller mill is to use the principle of material bed grinding for grinding materials, grinding, conveying, powder selection, drying, separation of metal blocks and ore, and so on. Under normal conditions, as long as through the short-term process debugging, roll mill can run smoothly. However, how to optimize the process parameters, ensure the quality, increase the output, reduce the energy consumption, improve the operation rate, and continuously improve the economic benefit is the central problem of the management and operation of vertical mill / roller mill.
The control of 1.1 air flow is generally controlled by 5000~7000Pa in order to ensure the proper air flow. The change of the internal pressure difference is mainly affected by the feed quantity when the other conditions remain unchanged. Therefore, the feed quantity should be stabilized.
When the mill vibration is obvious, the mill vibration of the 1.2 mill should be stopped, so as to ensure that the mill is not damaged. There may be some reasons for the excessive vibration, and the reasons should be analyzed to deal with the problem:
(1) the coating on the millstone is too thin or too thick;
(2) the metal foreign body enters the mill;
(3) feeding large amounts of hard materials;
(4) the air flow is too small, and the finished product can not be sent out in time;
(5) the speed of separator is too high and the cycle load is too large;
(6) damage of roller bearing;
(7) the proportion of hard materials in raw materials is too large, and the amount of fine powder is too little;
In the mill overload operation, vibration increases, at this time should observe the main motor current increase, alarm should be promptly dealt with.
Control of feed quantity in 1.3 mill
Keeping the thickness of material layer stable is the main content of operation control. The stability of material layer is the precondition of safe operation of mill, and the feed quantity in mill can be tested by three methods:
Clearance of grinding roll spacing device;
The power of the mill (i. e. the main motor current);
Measurement of belt scale;
If the material layer is too thick, the following phenomena will occur:
Mill pressure difference increases;
Mill vibration increase;
Mill current increased;
Increase of slag discharge in mill;
When the material layer is too thin, the following phenomena will occur:
Mill vibration increase;
The mill pressure difference becomes smaller;
Increase of main motor current;
Control of air volume in 1.4 mill
For example: HRM3600 mill designed a grinding air volume of 420000/h, in order to meet the requirements of material conveying and drying. In the process of operation, the air volume must be adjusted in time when the air volume changes greatly.
The air flow is too small:
Can not be finished timely output, grinding in circulation increases, the mill load, the fineness of product detail;
(2) the wind speed of the air ring is low, and the amount of slag discharged from the mill increases;
When the air volume is too high, the following will happen:
Product fineness coarsening;
Differential pressure increase in vertical mill;
(3) energy consumption increase of main fan;
1.5 product fineness control
Too coarse granularity of raw material will influence the clinker burning, rules resulted in increased yield and fineness of grinding power consumption in production, the operator must according to the laboratory every hour the results of the determination of raw meal fineness adjust speed of separator, the fineness control in the range of R0.08 = 14~16%.
The control of 1.1 air flow is generally controlled by 5000~7000Pa in order to ensure the proper air flow. The change of the internal pressure difference is mainly affected by the feed quantity when the other conditions remain unchanged. Therefore, the feed quantity should be stabilized.
When the mill vibration is obvious, the mill vibration of the 1.2 mill should be stopped, so as to ensure that the mill is not damaged. There may be some reasons for the excessive vibration, and the reasons should be analyzed to deal with the problem:
(1) the coating on the millstone is too thin or too thick;
(2) the metal foreign body enters the mill;
(3) feeding large amounts of hard materials;
(4) the air flow is too small, and the finished product can not be sent out in time;
(5) the speed of separator is too high and the cycle load is too large;
(6) damage of roller bearing;
(7) the proportion of hard materials in raw materials is too large, and the amount of fine powder is too little;
In the mill overload operation, vibration increases, at this time should observe the main motor current increase, alarm should be promptly dealt with.
Control of feed quantity in 1.3 mill
Keeping the thickness of material layer stable is the main content of operation control. The stability of material layer is the precondition of safe operation of mill, and the feed quantity in mill can be tested by three methods:
Clearance of grinding roll spacing device;
The power of the mill (i. e. the main motor current);
Measurement of belt scale;
If the material layer is too thick, the following phenomena will occur:
Mill pressure difference increases;
Mill vibration increase;
Mill current increased;
Increase of slag discharge in mill;
When the material layer is too thin, the following phenomena will occur:
Mill vibration increase;
The mill pressure difference becomes smaller;
Increase of main motor current;
Control of air volume in 1.4 mill
For example: HRM3600 mill designed a grinding air volume of 420000/h, in order to meet the requirements of material conveying and drying. In the process of operation, the air volume must be adjusted in time when the air volume changes greatly.
The air flow is too small:
Can not be finished timely output, grinding in circulation increases, the mill load, the fineness of product detail;
(2) the wind speed of the air ring is low, and the amount of slag discharged from the mill increases;
When the air volume is too high, the following will happen:
Product fineness coarsening;
Differential pressure increase in vertical mill;
(3) energy consumption increase of main fan;
1.5 product fineness control
Too coarse granularity of raw material will influence the clinker burning, rules resulted in increased yield and fineness of grinding power consumption in production, the operator must according to the laboratory every hour the results of the determination of raw meal fineness adjust speed of separator, the fineness control in the range of R0.08 = 14~16%.
