JPH057788A - Vertical crushing machine - Google Patents

Abstract

PURPOSE:To provide a vertical crushing machine capable of dealing promptly with the deterioration of crushing efficiency due to the insufficient bite of a material to be supplied into a crushing roller following the increased ratio of pulverized material and subsequent increased fine powder generation, and the heightening of a mill vibration value attributed to other causes as well as maintaining continued safely operation. CONSTITUTION:A constant 1 feed ware 80 is provided between a raw material hopper 70 and an upright crusher and at the same time, a grain size detector 130 which measures the powder rate of a raw material in transport is arranged. In addition, a control device 140 is provided which increases/decreases the supply amount of raw material, if the vibration measurement value by a vibration meter 150, the measurement value of a raw material pulverization rate and a raw material feed amount exceed their respective previously determined values.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical crusher for crushing raw materials such as limestone, slag, clinker, cement raw material, ceramics and chemicals by cooperation of a rotary table and a pulverizing roller.

[0002]

2. Description of the Related Art FIG. 4 is a kind of crusher for pulverizing raw materials such as limestone, slag, and cement raw materials into fine powder.
As shown in (1), a vertical crusher 1 having a rotary table and a crushing roller is widely used. This kind of crusher
A disk-shaped rotary table 3A which is driven by a speed reducer 2 by a motor 2A to rotate at a low speed in a lower portion of the cylindrical casing 15, and is driven to rotate by hydraulically contacting a portion equally dividing the outer peripheral portion of the upper surface thereof in the circumferential direction. And a plurality of crushing rollers 4 for

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 by a shaft 15 by a shaft 6, and by operating the hydraulic cylinder 9, The crushing roller 4 is pressed against the rotary table 3A to apply crushing pressure to the raw material. 3B is a dam ring provided on the outer peripheral edge of the rotary table 3A for adjusting the raw material layer pressure, 14 is a gas blowing annular space passage around the rotary table 3A, 14A is a gas supply passage, and 13 is raw material crushed by the blades 13A. A rotary separator for classification, 16 is an outlet for taking out a product together with gas, and 17 is a raw material charging chute. Reference numeral 140 is a vibrometer attached to the casing 15.

In such a vertical crusher, the raw material supplied to the central portion of the rotary table by the raw material feeding chute 17 receives the centrifugal force in the radial direction of the rotary table 3A and slides on the rotary table 3A. At times, the rotary table 3A receives a force in the rotation direction, and the rotary table 3A
It slides with A and performs a rotation somewhat slower than the rotation speed of the rotary table 3A. The above two forces, that is, the radial direction force and the rotational direction force are combined, and the raw material is the rotary table 3.
A spiral locus is drawn on A to move to the outer peripheral portion of the rotary table 3A. Since the roller is pressed against the outer periphery and is rotating, the raw material in which the spiral is drawn enters the crushing roller 4 and the rotary table 3A from a direction forming an angle with the roller axial direction and is bitten. It is crushed and crushed.

On the other hand, at the base of the casing 15, gas such as air or hot air is introduced by a duct,
This gas blows up from the annular space portion 14 between the outer peripheral surface of the rotary table 3A and the inner peripheral surface of the casing, so that the pulverized fine powder is entrained in the gas and the casing 1
5, the blade 1 of the separator 13 that is located in the upper part
The product having a predetermined particle size is subjected to the classification action by 3A and is discharged together with the gas from the discharge port 16 and sent to the next step.

[0006]

In the conventional vertical crusher as described above, a considerable amount of the material to be crushed reaching the biting side of the crushing roller is bitten by the crushing roller on the table. It is normal for it to be washed away into the annular space. Then, among the objects to be crushed that are pushed into the annular space on the biting side of the crushing roller, those with a large particle size become stones and fall into the annular space to increase the amount of stones and increase the amount of processing work. Increase. Further, among the objects to be crushed that have been swept into the annular space, those having a small particle size are scattered again, so that the load applied to the separator is increased and the classification efficiency is likely to be lowered. Further, a large amount of the object to be crushed is forced to flow into the annular space portion, which increases the ventilation pressure loss in the annular space portion, thereby increasing the fan power.

[0007] In the conventional operation control, especially in the high fine crushing automatic operation, the pulverization amount, that is, the raw material supply amount is controlled so that the mill pressure difference is constant, or the raw material is controlled so that the mill power is constant. The supply was controlled. In these methods, the particle size distribution of the raw material to be charged changes suddenly, and
If the amount of powder of less than 00μ is very large,
The raw material does not enter well between the rotary table and the crushing roller, and it is difficult for the raw material to slip and properly bite, and the crushing work does not progress efficiently. As a result, the amount of raw material introduced into the mill increases, vibration gradually increases, and eventually operation becomes impossible, resulting in loss of control. There was the inconvenience of adjusting. In particular, mill vibration often occurs when a raw material having a high powder ratio and relatively poor pulverizability is used, and when the vibration value (amplitude) is particularly large, There were occasions when the vehicle was damaged or rendered inoperable, and forced to suspend operation.

Therefore, as a countermeasure against the occurrence of a large vibration, in order to move away from the resonance region by changing the frequency of the raw material layer of the crushing part, the table weir height (dam ring height), It is conceivable to change the crushing pressure and table rotation speed by changing them. Of these, changing the rotary table drive device is too expensive to implement and the feasibility is low. However, there is a problem that changing the grinding pressure changes the product grain size to the desired one. The actual situation is to switch to operation operation and reduce the mill throughput, which is troublesome. The generation of these vibrations tended to occur more frequently in the fine crushing or ultra fine crushing than in the intermediate crushing region.

[0009]

In order to solve the above-mentioned problems, the vertical crusher of the present invention has a plurality of rotatable crushing rollers arranged on the upper surface of the outer peripheral portion of a rotary table and supplies the crushing roller to the center of the rotary table. The raw material is pulverized between the upper surface of the rotary table and the peripheral surface of the pulverizing roller by applying a predetermined pulverizing pressure to the pulverizing roller, and the raw material from the raw material hopper is pulverized in a vertical pulverizer equipped with a vibrometer on the casing. Equipped with a constant feed ware for transportation to the machine, and a particle size detector for measuring the raw material powder ratio of the raw material being transported is arranged in the constant feed ware, and the measured value of the vibrometer is set to a preset value. When it exceeds, or when the measured value of the raw material powder ratio by the particle size detector exceeds a preset value, the output speed of the variable speed electric motor for driving the constant feed wear is determined. Having a control device for further.

[0010]

In the vertical crusher of the present invention, the vibration value (amplitude) measured by the vibrometer attached to the casing of the vertical crusher and the raw material powder ratio of the transportation material arranged in the constant feed ware are set. The measured value of the particle size detector to be measured and the raw material supply amount are converted into electric signals every moment and transmitted to the control device, and the vibration value (allowable vibration value) and raw material powder preset by the comparator inside the control device are transmitted. Rate (the allowable ratio of fine powder in the raw material), and when either set value is exceeded, as a countermeasure, a measure to reduce the amount of raw material supplied to the crusher according to the extent of the exceeded value. Take action. When the measured value falls within the set value, the raw material supply amount is increased to the original state and the operation returns to stable operation.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 to 3 show an embodiment of a vertical crusher of the present invention, FIG. 1 is a flow sheet, FIG. 2 is a control block diagram of a control device, and FIG. 3 is a control system diagram. In the figure, 1 is a vertical crusher, 60 is a raw material conveyor, 70 is a raw material hopper, 80 is constant feed wear, and 80a.
Is a variable speed electric motor for the same purpose, 90 is a dust collector, 100 is a suction fan, 110 is a stone exhaust conveyor, 120 is a bucket elevator, 130 is a particle size detector, 140 is a controller, 150
Is a vibrometer. The control device 140 houses therein a setter, a comparator, a controller (consisting of a regulator and an operating device), and an amplifier. Since each device of the main body of the vertical crusher 1 is as described in the related art, the description is omitted.

Next, the operation of the control device 140 will be described. As shown in FIG. 2, the vibrometer 150 and the particle size detector 130 are measured at every time interval set by the timer.
Is converted into an electric signal and input to the control device 140. This measurement value (vibration value and raw material powder rate) and three pieces of information on the raw material supply amount, and three set values (allowable limit vibration value, limit raw material powder rate, rated raw material supply amount) that have been input to the presetter in advance. Is compared by a comparator, and if it deviates from the set value, a command is issued to the variable speed electric motor 80a for driving the constant feed wear 80 through the controller according to the control system procedure as shown in FIG. Increase or decrease the amount of raw material supply.

The controller comprises an adjuster and an operating device,
The controller regulates the range of increase or decrease of the output rotation speed of the constant feed wear 80 according to the degree of excess of the measured value (vibration value or raw material powder rate) with respect to the set value. The control operation is proportional operation ( P operation), integral operation (working operation), derivative operation (D operation), proportional integral operation (PI operation), proportional derivative operation (PD operation), etc. Make an appropriate selection above and use it. The operation unit transmits an operation command to the variable speed electric motor 80a based on the command from this controller. The lines with arrows in the figure show the flow of signals.

FIG. 3 shows one of the control systems for such operation commands.
An example is shown. When the vibration value is equal to or less than the allowable value (setting value), the operation is continued as it is when the rated raw material is being supplied, and the amount is increased when the supply amount is less than the rated value. If the vibration level during operation exceeds the permissible value, if the cause is excessive raw material supply, or if it is due to an increase in the raw material powder rate, the raw material supply amount is reduced to a small or medium range. When the amount of raw material supply is not large and the raw material powder rate is lower than the set value but the vibration level is high, it is considered to be caused by some other cause. In order to avoid this, it is necessary to sharply reduce the amount of raw material supply immediately. Since the timers A to D shown in FIG. 3 have different time required to recover the original state, the timers A to D are appropriately determined according to the actual situation.
Increasing the set time of the timer D is desirable for stable operation.

The particle size detector 130 is an application of a measuring device of a constant feed wear (hereinafter referred to as CFW) 80. The CFW 80 is equipped with a load detecting section and a belt traveling distance detecting section in one part of a conveyor, and is to be weighed. While the crushed raw material is being sent, the load on the belt and the distance traveled by the belt are converted into electrical signals and transmitted to the computing controller. In the arithmetic controller, the passage cross-sectional area is integrated with the belt travel distance to calculate the passage volume, and the instantaneous bulk specific gravity is calculated from the accumulated weight and the accumulated passage volume. When the passing volume is maintained at a constant value, the bulk specific gravity becomes large and the bulk specific gravity becomes small when the raw material is mostly in the form of lumps with little powder. On the other hand, when there are few lumps and a large amount of fine powder, the porosity decreases, and the bulk specific gravity increases accordingly. Therefore, there is a correlation between the bulk specific gravity and the ratio of the fine powder contained in the raw material, that is, the raw material powder rate, and the value of the raw material powder rate can be roughly known by knowing the bulk specific gravity. The particle size detector 130 is an application of the above principle. A load cell is used for the load detector that detects weight.

As described above, after the operation is changed and the set time of each timer elapses, the measured value and the set value are compared again, and the original stable operating state is restored even if the vibration level is lowered. By performing the automatic control by the feedback mechanism as described above, it is possible to prevent the operation stoppage and the equipment damage due to the operation failure in response to the increase of the raw material powder rate and the increase of the vibration level due to other causes and the overload of the mill. be able to.

[0017]

As is apparent from the above description, in the vertical crusher of the present invention, the raw material powder ratio is preset when the raw material is supplied with the rated raw material supply amount, the allowable vibration level and the raw material particle size that are greatly changed. By appropriately controlling the raw material supply amount when the measured value exceeds these set values using the appropriate value as an index, it becomes possible to automatically avoid the uncontrollable operation and the suspension of operation. Therefore, driving operability is improved, and long-term continuous stable operation can be continued, so productivity is improved.

[Brief description of drawings]

FIG. 1 is a flow sheet of a vertical crusher showing an embodiment of the present invention.

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

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

FIG. 4 is an overall vertical sectional view of a conventional vertical crusher.

[Explanation of symbols]

 1 Vertical Grinder 3A Rotary Table 4 Grinding Roller 17 Raw Material Injecting Chute 22 Hydraulic Cylinder 60 Raw Material Conveyor 70 Raw Material Hopper 80 Constant Feed Wear 80a Variable Speed Motor 90 Dust Collector 100 Suction Fan 110 Stone Exhaust Conveyor 120 Bucket Elevator 130 Particle Size Detection Vessel 140 control device 150 vibration meter

Claims (1)

Claim: What is claimed is: 1. A plurality of rotatable crushing rollers are arranged on the upper surface of the outer periphery of a rotary table, and the raw material supplied to the center of the rotary table is rotated by applying a predetermined crushing pressure to the crushing roller. Grind between the table top surface and the grinding roller peripheral surface, and
A vertical crusher with a vibrometer attached to the casing is equipped with a constant feed ware that transports the raw material from the raw material hopper to the crusher, and a particle size detector that measures the raw material powder ratio of the raw material being fed by a constant force. When the measurement value of the vibrometer exceeds a preset value, or when the measurement value of the raw material powder ratio by the particle size detector exceeds the preset value, A vertical crusher equipped with a control device for changing the output speed of a variable speed electric motor for driving constant feed wear.