INPUT:0-80mm
OUTPUT:80-325um
Application: For various types of non-metallic mineral grinding, such as limestone, calcium carbonate, calcite, barium sulfate, gypsum, talc, pyrophyllite, quartz, feldspar, barite, etc.
Cement raw material grinding, slag powder production, calcium carbonate pulverization, pulverized coal preparation station, gypsum powder processing, power plant desulfurization, phosphate rock grinding, metallurgical industry, ultra-fine grinding industry, other non-metallic mineral powder, etc.
Structure and working principle of vertical roller mill
Structure of VRM
VRM vertical mill mainly consists of separator, grinding roller device, grinding table device, pressure device, reducer, motor and shell. The supporting equipment includes thin oil lubrication station, hydraulic oil station, dry oil station, main motor and electrical control cabinet.
The separator is a high-efficiency and energy-saving powder separating device; the grinding roller is a component used for crushing materials; the grinding table which is the place where the grinding roller crushes the material is fixed on the output shaft of the reducer, and the pressure device is a component that provides sufficient pressure to the grinding roller to crush the material. Motor drives the grinding table to rotate through the reducer, and the material is brought to the grinding area by centrifugal force.
Through the reducer, the motor drives the grinding table to rotate, so that the material falls from the feeding opening to the center of the grinding table through the air-locking feeder, and the hot air enters into the grinding mill from the air inlet. With the rotation of the grinding table, the material is brought to the edge of the grinding table under the action of the centrifugal force by the high-speed airflow of the wind ring. The large particles fall directly onto the grinding table and will be reground. When the material in the airflow enters the upper separator, under the action of the rotor, the coarse powder falls from the cone to the grinding table and is reground. The qualified fine powder gets out of the mill together with the airflow and collected by the dust collecting device --- which is the product, and the moisture-containing material is dried in the process of contact with the hot gas. By adjusting the hot air temperature, it can meet the requirements of different humidity materials and achieve all the required product moisture. By adjusting the separator, the thickness required for different products can be achieved.
The material is mainly crushed and ground by the weight of the grinding roller and the pressure of the pressing device. During the grinding process, the material is always subjected to the pressure of the grinding roller, and the grinding roller and the grinding table are not purely rolling, and the material is subjected to multi-direction force, thus improving the grinding capacity and grinding efficiency of the mill;
When the material enters the mill, it is in full contact with the hot air, it is pulverized and floated in the hot gas, and the heat can be fully exchanged. The material is also dried while being ground;
The grinding pressure of the grinding roller is provided by the hydraulic system, and is applied to the material through the pressing device and the transmission device to the grinding roller. By adjusting the pressure of the hydraulic system, the grinding pressure is changed to meet the different grinding requirements for different hardness materials;
In order to avoid the violent vibration caused by the direct contact between the grinding roller and the grinding table during the empty working of the mill, there should be a certain gap between the grinding roller and the grinding table. Therefore, a limit device for controlling the gap size is specially designed, and the thickness of the material under the grinding roller can be known at any time by the limiting device, thus ensuring that the grinding machine operates under safe and economical working conditions;
Model |
VRM800K |
VRM1100K |
VRM1250K |
VRM1300K |
VRM1500K |
VRM1700K |
VRM1900K |
VRM2200K |
Capacity (t/h) |
0.5-3 |
1-6 |
1.5-9 |
2-13 |
7-25 |
10-25 |
15-35 |
18-45 |
Max. Feeding size(mm) |
0-15 |
1-20 |
0-20 |
0-25 |
0-35 |
0-35 |
0-40 |
0-40 |
Moisture of raw material (%) |
<10 |
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End product finesse |
80-325 mesh, adjustable |
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Final moisture (%) |
≤1 |
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Main motor power (kW) |
45 |
110 |
132 |
180 |
250 |
355 |
450 |
600 |
Process No.1: Single pulse dust collector-open circuit system
The raw materials of the system are raised to the required height by the bucket elevator. After the iron removal, the materials are placed in the intermediate hopper. The feeding quantity is preset, the closed quantitative feeder weighs the materials and feeds them into vertical mill for grinding. The qualified powder product is collected by a box-type pulse bag filter. The number of equipment is reduced and the system configuration is simplified. After the collection of the product, it is fed into the finished silo by a bucket elevator through a screw feeder. The system is of simple structure, less equipments and less equipment investment, the drying heat source is not needed, operating cost is low, so it is adaptable to dry materials (water content <6%), and drying is not required.
2 Bucket elevator
3 Iron remover
4 Belt conveyor
5 Intermediate silo
6 Closed dosing machine
7 Vertical mill
8 Box pulse bag filter
10 Fan
11 Silencer
12 Finished product silo
13 Bucket elevator
14 Screw conveyor
15 Iron remover
16 Returning belt conveyor