JP2795362B2 - Crushing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The crushing equipment of the present invention uses a vertical crusher as a preliminary crusher for a finishing mill such as a ball mill, and is particularly hard, such as cement clinker and blast furnace slag, which is hard to crush. In addition, the present invention relates to a crushing apparatus for finely crushing a material having high abrasion.

[0002]

2. Description of the Related Art As one type of pulverizer for finely pulverizing chemical products such as limestone, blast furnace slag, and cement raw material into powder, as shown in FIG. 6, a vertical pulverizer equipped with a rotary table and a pulverizing roller. 1 is widely used. This type of crusher has a motor 2 at the lower part of the cylindrical casing 15.
A, a disk-shaped rotary table 3A driven by the speed reducer 2 and rotated at a low speed, and a plurality of crushing rollers 4 driven to rotate by being hydraulically pressed against a portion equally dividing the outer peripheral portion of the upper surface in the circumferential direction. It has.

The crushing roller 4 is connected to a piston rod 10 of a hydraulic cylinder 9 via an arm 5 and an arm 7 which are pivotally supported on a casing 15 by a shaft 6 so that the crushing roller 4 is actuated. The crushing roller 4 is pressed on the rotary table 3A to apply crushing pressure to the raw material. 3B is a dam ring provided on the outer periphery of the rotary table 3A to adjust the thickness of the raw material layer, 14 is an annular space passage for gas blowing around the rotary table 3A, 14A is a gas supply path, and 13 is a raw material pulverized by the blade 13A. A rotary separator for classification, 16 is an outlet for taking out the product together with the gas, and 17 is a raw material input chute.

In such a vertical pulverizer, the raw material supplied to the center of the rotary table by the raw material charging chute 17 receives the centrifugal force in the table radial direction by the rotation of the rotary table 3A and slides on the rotary table 3A. When a force in the rotating direction is received by the rotating table 3A,
A slides with A and makes a rotation somewhat slower than the rotation speed of the turntable 3A. The above two forces, that is, the force in the radial direction and the force in the rotational direction are synthesized, and the raw material is
A moves to the outer periphery of the turntable 3A in a spiral locus on A. Since a roller is pressed against this outer peripheral portion and rotated, the raw material describing the spiral enters the crushing roller 4 and the rotary table 3A from a direction forming an angle with the roller axis direction and is caught. Rarely crushed.

On the other hand, a gas such as air or hot air is guided to the base of the casing 15 by a duct.
This gas blows up from the annular space 14 between the outer peripheral surface of the turntable 3A and the inner peripheral surface of the casing, so that the pulverized fine powder accompanies the gas and the casing 1
5, the blades 1 of the separator 13 located above.
The product having the predetermined particle size is subjected to the classification action by 3A, and is discharged together with the gas from the outlet 16 and sent to the next step.

[0006] In recent years, the demand for the product particle size of the pulverized raw material has been increasing year by year, and the finer product particle size has been more and more desired as referred to as fine pulverization or ultra-fine pulverization. Therefore, it is difficult to meet the demand with a single crusher. For this reason, for example, a vertical crusher is used as a preliminary crusher before charging the raw materials into a finishing mill such as a ball mill. A method has been adopted in which a crushed product is sieved with a vibrating sieve and only fine powder is supplied to a finishing mill. FIG. 5 shows a flow sheet in this case. The raw material of the raw material hopper 70 supplied by the raw material conveyor 60 is pulverized by the vertical pulverizer 1 through the constant feedware 80, and the product is vibrated through the bucket elevator 90. It is guided to a sieve 100 for screening, and only fine powder is pulverized by a finishing mill (ball mill) 110, and the oversized product is again pre-pulverized by the vertical pulverizer 1. 120
Is a classifier, 130 is a dust collector, and 140 is a suction fan.

[0007]

In the above-described two-stage pulverization by pre-pulverization and main pulverization, the pre-pulverized product is sieved with a vibrating sieve, and maintenance of the sieve becomes a problem. That is, for example, when the raw material is particularly abrasive, such as when finely pulverizing a cement clinker containing slag, it is generally necessary to inspect the vibrating sieve and replace parts every two to three months. Had to be shut down for several hours, which inevitably led to a drop in productivity due to downtime. Therefore, there has been a problem to be solved by adopting an alternative means instead of the vibrating sieve.

Further, when a hard and poorly crushable raw material such as slag or clinker is crushed to a very small size, a strong pressing force is applied to the crushing roller, so that the thickness of the raw material layer is relatively small, and therefore vibration is liable to occur, which is likely to occur. The vibration value (amplitude) is larger than that of ordinary raw materials, and it is difficult to maintain stable continuous operation.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a grinding apparatus according to the present invention comprises a vertical grinding machine used as a preliminary grinding machine, and a vertical grinding machine. Raw material supply equipment equipped with a weighing machine for supplying raw materials to the machine, a finishing mill for crushing the crushed product of the vertical crusher, a classification device for classifying fine powder after crushing, and collecting fine powder after classification Crushing equipment comprising a dust collecting device and a suction fan, wherein the vertical crusher has a plurality of rotatable crushing rollers disposed on an upper surface of an outer peripheral portion of a rotary table, and the crushing rollers are connected to the rotary table. A crusher for crushing the raw material between the upper surface of the rotary table and the peripheral surface of the crushing roller, comprising a vibrometer mounted on a casing, Equipped with a layer thickness gauge to measure the material layer thickness between rollers And the vibration meter readings and the layer thickness meter readings and the material supply equipment weighing machine to enter preset algorithm by the vibration level determined the raw material layer thickness determination and feed the indication of A control device for changing the hydraulic pressure of the hydraulic means or transmitting an operation command signal for changing the raw material supply amount when the supply amount is determined and deviates from each set appropriate value; The table was provided with a discharge port for crushed products at the lower part of the outer periphery of the table.

[0010]

The pulverizing equipment of the present invention is a two-stage pulverizer in which coarse particles of the pulverized product pulverized by a vertical pulverizer adopted as a preliminary pulverizer are supplied to a finishing mill and pulverized. The fine powder obtained by classifying the fine powder of the die grinder is refined, and the coarse powder after classification is again pulverized by the finishing mill, so that the pulverization efficiency is high. In addition, since the vibrating sieve is omitted in the supply path to the finishing mill, the number of operation stoppages is small, and the productivity is improved. Furthermore, when vibration of the vertical grinding machine is generated, the pressing force of the grinding roller is changed by the vibrometer and the layer thickness gauge provided in the vertical grinding machine and the difference between the measured value and a preset value. The control device that controls the raw material supply amount while appropriately maintaining the raw material layer thickness can suppress the continuation of the vibration generation and calm down, so that stable continuous operation can be performed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 4 show an embodiment according to the present invention. FIG. 1 is a flow sheet of a crusher, FIG. 2 is a block diagram of a control device, FIG. 3 is a control system diagram, and FIG. It is a longitudinal cross-sectional view. In the figure, 1 is a vertical crusher, 2
A is a variable speed motor, 60 is a raw material conveyor, 70 is a raw material hopper, 80 is a constant feed ware, 80a is a variable speed electric motor for the same use, 80b is a weighing machine, 110 is a finishing mill (for example, a ball mill or a rod mill), and 120 is a classification. The device, 130 is a dust collector, and 140 is a suction fan. A vibrometer 200 is mounted on the casing 15 of the vertical crusher 1, and a layer thickness meter 210 is mounted on the arm 5 of the crush roller 4 as shown in FIG. A control device 220 is connected to the vibrometer 200, the layer thickness meter 210, the variable speed motor 2A, and the variable speed motor 80a of the constant feed ware 80. The finishing mill 110 is usually a ball mill or a rod mill, and a classifier (for example, a cyclone separator is used) 120 is connected to a closed circuit, and the classified coarse powder is supplied again to the inlet of the finishing mill 110. The fine powder is collected by a dust collector 130 such as a bag filter, a cyclone, and an electric dust collector, and becomes a product.

Next, among the structures of the vertical pulverizer 1, the layer thickness meter 210 and the control device 220 will be described with reference to FIGS. First, the layer thickness meter 210 will be described. As shown in FIG. 4, the movement of the pulverizing roller 4 which moves up and down in response to the change of the raw material layer thickness that fluctuates during operation is controlled by the arm 5 which rotates about the rotation axis 6. The displacement is measured by a layer thickness gauge 130 to which a differential transformer is applied, for example, as a displacement converter. That is, the primary coil E as shown in FIG. And the secondary coil A, put core C made of magnetic material between is B, a constant AC voltage to the primary coil A E _P
Leave excited, when the backward before linked via an arm 5 and rod R, the reactance is changed by the movement of the core C against the secondary coil A and the secondary coil B, both the induced voltage E _A and E _A difference is generated in _B , and an output potential difference E _O is obtained, from which the displacement of the core C can be measured. The other structure of the vertical crusher 1 is the same as that described in the related art, so that the description is omitted.

Next, the operation of the control device 220 will be described. As shown in FIG. 2, the measurement results of the vibrometer 200, the layer thickness meter 210, and the weighing machine 80b, which are measured every time interval set by the timer, are converted into electric signals and input to the control device 220. The three pieces of information (vibration value, raw material layer thickness, and raw material supply amount) are compared with set values input to the setter in advance by a comparator. The hydraulic unit (not shown) of the hydraulic cylinder 9 (shown in FIG. 5) is controlled via the controller to increase or decrease the pressing force (oil pressure) of the crushing roller 4. The set values include the reference vibration level, reference material layer thickness, and rated speed (variable speed motor for constant feed wear drive). The controller is composed of a controller and an operating device. The controller indicates the range of increase and decrease of the hydraulic pressure of the hydraulic cylinder 9 according to the difference between the measured value of the vibration value or the raw material layer thickness and the set value. The control operation includes proportional operation (P operation), integration operation (I operation), differentiation operation (D operation), proportional integration operation (PI operation), proportional differentiation operation (PD operation), etc. Can be used properly depending on. In addition to the above, the controller also has a role of indicating a width of decreasing the raw material supply amount in accordance with how the measured value exceeds the set value of the vibration. The raw material supply amount is obtained by integrating the measured values of the weighing machine 80b of the constant feed ware 80 in units of time.

The operation device transmits an operation command to the hydraulic unit or the variable speed motor 80a based on the instruction from the controller. The line with the arrow in the figure indicates the signal flow.

The flow of the control system of these control devices 220 is as shown in FIG. That is, the vibration value and the thickness of the raw material layer are measured at the time intervals specified by the timer during operation, and when the measured vibration value is larger than the reference vibration level (for example, half-amplitude 50 μm), when the raw material layer thickness is lower than the set range, Decrease the pressure and increase the rotation speed of the rotary table when it is higher than the set range. When the vibration level is high even though the raw material layer thickness is within the appropriate range, the raw material supply amount is temporarily reduced to avoid this situation. Also,
When the vibration level is within the reference level and the raw material supply amount does not reach the rating, the raw material supply amount is increased.

In this way, after a certain time elapses by the timer after the operation is changed, the vibration value measured by the vibrometer 200 and the measured value of the raw material layer thickness measured by the layer thickness meter 210 are compared again with the set value. Sometimes the above operation is repeated.
The set value of the vibration value is about 50 μm in half amplitude, and the set value of the raw material layer thickness depends on the type of raw material, the model of the crusher, and the particle size of the product, and cannot be determined unconditionally. The set layer thickness increases as the grain size increases. It is advisable to grasp the situation based on operation results and test runs and select an appropriate value.

By performing the automatic control having the feedback mechanism as described above, the vibration value suddenly increases, or the water content of the feed material suddenly decreases (or increases) during operation, and the grinding efficiency decreases. Even if the vibration value increases due to poor biting, the raw material supply amount and the raw material layer thickness are improved by the above operation, and the raw material biting is improved again to maintain the stable operation. You can return to the state.

In the pulverizing equipment of the present invention, such a vertical pulverizer 1 carries out preliminary pulverization, and after classification, fine powder is conveyed to a classification device 120 by air conveyance, and coarse particles are supplied to a finishing mill 110 for pulverization. Then, fine particles having a desired particle size after the finish pulverization are collected by a dust collector 130 by a classifier (cyclone separator) 120 connected to the finishing mill 110 in a closed circuit. Therefore, there is no need for a classifier such as a vibrating sieve between the vertical mill 1 and the finishing mill 110, and since the configuration of the entire plant is simple, both equipment costs and running costs are low. Frequent shutdowns due to replacement of worn parts are avoided, especially with raw materials that are highly abrasive.

[0019]

Since the crushing equipment of the present invention is constructed as described above, the following effects can be obtained. Since fine powder among the pulverized products of the vertical pulverizer as the pre-pulverizer does not pass through the finishing mill, over-pulverization in the finishing mill can be prevented and the pulverizing efficiency is improved. When the vibration of the vertical grinding machine is generated, the pressing force of the grinding roller and the amount of raw material supplied are automatically changed temporarily, the thickness of the raw material layer is kept within an appropriate range, and the vibration is calmed down. It can be operated stably. Since a vibrating sieve is not used unlike the prior art, the interval between replacement of worn parts is large, the continuous operation period is long, productivity is improved, and maintainability is improved. There is no classification equipment between pre-milling and finishing milling, and the equipment cost is low.

[Brief description of the drawings]

FIG. 1 is a flow sheet showing an embodiment of the crushing equipment of the present invention.

FIG. 2 is a block diagram showing an embodiment of a control device of a vertical crusher according to the crushing equipment of the present invention.

FIG. 3 is a control system diagram of a vertical crusher according to the crushing equipment of the present invention.

FIG. 4 is a schematic explanatory view (longitudinal sectional view) of a layer thickness gauge of a vertical pulverizer according to the pulverization equipment of the present invention.

FIG. 5 is a flow sheet of a conventional grinding facility.

FIG. 6 is an overall vertical sectional view of a conventional vertical crusher.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vertical grinder 2 Reduction gear 2A Motor 2B Controller 3A Rotary table 4 Grinding roller 5 Arm 6 Rotating shaft 15 Casing 60 Raw material conveyor 70 Raw material hopper 80 Constant feedware 80a Variable speed motor 80b Weighing machine 90 Bucket elevator 100 Vibrating sieve 110 Finishing mill 120 Classifier 130 Dust collector 140 Suction fan 200 Vibrometer 210 Layer thickness meter 220 Controller A Secondary coil B Secondary coil C Core E Primary coil R Rod

Claims (1)

(57) [Claims] 1. A vertical mill used as a preliminary mill, a raw material supply facility equipped with a weighing machine for supplying raw materials to the vertical mill, and a finishing mill for milling pulverized products of the vertical mill. And a classifying device for classifying fine powder after pulverization, a dust collecting device for collecting fine powder after classification, and a suction fan, wherein the vertical pulverizer is an outer peripheral portion of a rotary table. A plurality of rotatable crushing rollers are disposed on the upper surface, and a hydraulic means for pressing the crushing rollers against the rotary table is provided, and a vertical crusher for crushing the raw material between the upper surface of the rotary table and the peripheral surface of the crushing roller is provided. a machine, with mounting the vibrometer to the casing, with a layer thickness meter which measures a material layer thickness between the rotary table grinding roller during operation, and an instruction value of the vibration meter and before <br/> of the serial layer thickness meter readings and of the weighing machine of the raw material supply facilities When deviates from the respective set appropriate value by performing determination of the determination and the material layer thickness determination and raw material supply amount of the vibration level by preset algorithm to input示値,
A crushing equipment comprising a control device for transmitting an operation command signal for changing the hydraulic pressure of the hydraulic means or changing the raw material supply amount, and a discharge port for crushed products at a lower outer periphery of the rotary table.