JP5057212B2 - Control method of vertical crusher - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control method of a vertical grinder capable of effectively preventing abnormal vibration produced in operation, and a control device suitable for use in the control method. <P>SOLUTION: The vibration value of the vertical grinder 1 is preliminarily measured while detecting the difference pressure between the gas pressures of a gas inlet 33 and a product outlet 39 during the operation of the vertical grinder 1 and the state of the difference pressure immediately before the measured vibration value exceeds the allowable range of the vertical grinder 1 is recorded as a boundary difference pressure pattern. During the control operation of the vertical grinder 1, the number of rotations of a turntable is reduced when the detected difference pressure almost coincides in comparison with the boundary difference pressure pattern to prevent abnormal vibration. The abnormal vibration of the vertical grinder easily produced when a raw material is finely ground is estimated from the difference pressure of a gas and suppressed by adjusting the number of rotations of the turntable. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a control method and a control apparatus for a vertical crusher that mainly uses coal, oil coke, limestone, slag, clinker, cement raw materials, chemicals, etc. as raw materials. The present invention relates to a control method and a control apparatus for a vertical crusher suitable for preventing or suppressing abnormal vibrations that are likely to occur when finely pulverizing a powder.

  Conventionally, a crusher called a vertical crusher (sometimes referred to as a vertical mill or a vertical roller mill) has been widely used as a crusher for crushing coal, oil coke and the like.

  In recent years, in particular, the number of cases in which raw materials are finely pulverized by a vertical pulverizer is increasing, and the number of vertical pulverizers having a classification mechanism in the vertical pulverizer is increasing. As a vertical crusher equipped with a classification mechanism, a conventional technique as disclosed in Patent Document 1 is known.

Japanese Patent Laid-Open No. 5-104012

  The vertical pulverizer shown in Patent Document 1 conveys and raises the pulverized raw material by an airflow blown from the lower part of the pulverizer, and is also conveyed by the airflow by a classification mechanism arranged at the upper part in the vertical pulverizer. This is a vertical pulverizer of a type that selects only fine powder from raw materials and takes it out of the apparatus, and is a type of vertical pulverizer generally called an air sweep type.

  Hereinafter, the structure of the air swept type vertical crusher disclosed in Patent Document 1 will be briefly described. The vertical crusher disclosed in Patent Document 1 includes a rotary separator having a plurality of rotary blades as a classification mechanism above a rotary table, and vertically penetrates the central axis of the rotary separator. The material input chute is arranged. And it is comprised so that a raw material can be injected | thrown-in on a turntable from a raw material inlet through a raw material injection chute (it may be called supply).

  The raw material supplied to the center of the rotary table from above the rotary table by the raw material charging chute moves toward the outer periphery of the rotary table while drawing a spiral trajectory on the rotary table. A dam ring is provided on the outer peripheral edge of the rotary table and is configured to maintain a required raw material thickness on the rotary table, so that the raw material moved to the outer peripheral part of the rotary table is dammed by the dam ring, It is bitten by the rotary table and grinding roller and crushed.

  In addition, a part of the raw material that is pulverized by the rotary table and the crushing roller gets over the dam ring that is provided around the outer edge of the rotary table, and is a ring that is a gap between the outer peripheral portion of the upper surface of the rotary table and the casing. Head to the passage (sometimes called an annular space).

During the operation of the vertical pulverizer, gas is introduced into the vertical pulverizer from the gas inlet port provided at the lower part of the pulverizer by a blower such as an exhaust fan. It is discharged out of the machine from the upper outlet. As a result, in the casing of the vertical crusher, a gas flow is generated from the lower side of the rotary table toward the upper side of the rotary separator.
Accordingly, a part of the raw material that has reached the annular passage over the dam ring is blown up by the gas flow and rises in the casing.

  The airflow rising in the casing is an airflow rising while turning due to the influence of the rotating separator. Therefore, among the raw materials blown up by the airflow, the raw material having a large diameter and a large weight falls below the casing due to the weight, or deviates from the airflow by the centrifugal force generated in the raw material itself by swirling by the airflow. For example, it falls below the casing and cannot pass through the rotating separator. The material that has failed to pass through the rotating separator and has fallen is again caught in the grinding roller and crushed. Note that the raw material having a small diameter passes through the blades, passes through the rotary separator, and is taken out from the upper outlet.

  A raw material having a particularly large particle diameter among the raw materials that have reached the annular passage falls below the rotary table from the annular passage and is taken out of the vertical crusher 1 from the lower outlet, and then a conveyor such as a bucket elevator. Then, the material is again introduced from the raw material inlet of the mold grinder and pulverized.

  In addition, what is likely to be a problem with the above-described vertical crusher is abnormal vibration of the vertical crusher. In Patent Document 1, a temporal change of the raw material layer thickness is monitored during operation of the vertical crusher, and when the raw material layer thickness monotonously decreases in a preset time width, the raw material layer thickness on the rotary table is set. In order to improve and avoid vibrations, a control method for a vertical crusher that adjusts the rotation speed of a rotary table to prevent abnormal vibrations is disclosed.

In many cases, the vibration can be avoided by adjusting the thickness of the raw material layer on the rotary table according to the above-described conventional technology, but the thickness of the raw material layer on the rotary table hardly changes during the operation of the vertical crusher. Regardless, abnormal vibration may occur.
Although the cause of this is not clear, as one factor, there is a tendency that abnormal vibration is likely to be induced when a large amount of fine powder is contained in the raw material to be crushed in the vertical crusher. However, conventionally, even in such a case, there is only a method for avoiding vibration by changing operating conditions in a coping manner, and a control method and a control device for a vertical crusher that can effectively prevent vibration are required. It was.

  The present invention has been made in view of the above demands, and relates to a control method and a control apparatus for a vertical grinder suitable for preventing abnormal vibration of the vertical grinder.

In order to achieve the above object, a method for controlling a vertical crusher according to the present invention includes:
(1) A raw material provided on a rotary table having a plurality of rotatable grinding rollers is ground between the rotary table and the grinding roller, and the ground raw material is provided below the rotary table. In the control method of the vertical crusher which is blown up by the gas introduced from the gas inlet and taken out together with the gas from the product outlet provided above the rotary table, the gas at the gas inlet and the product outlet is previously operated. The vibration value of the vertical crusher is measured while detecting the differential pressure from the pressure, and the state of the differential pressure immediately before the vibration value exceeds the allowable range of the vertical crusher is recorded and controlled as a boundary differential pressure pattern. When the differential pressure during operation matches the boundary differential pressure pattern, the rotational speed of the rotary table is reduced.

(2) In the method for controlling a vertical crusher according to (1),
The differential pressure immediately before the vibration value exceeds an allowable range of the vertical pulverizing apparatus, is recorded as a boundary differential pressure pattern.

(3) In the method for controlling a vertical crusher according to (1),
The temporal change of the differential pressure immediately before the vibration value exceeds an allowable range of the vertical pulverizing apparatus, is recorded as a boundary differential pressure pattern.

  According to the present invention, the abnormal vibration of the vertical pulverizer that is likely to occur when the raw material is finely pulverized can be predicted from the differential pressure of the gas flowing in the vertical pulverizer. Abnormal vibration can be suppressed by reducing the rotation speed of the rotary table.

Hereinafter, an example of a preferred embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is an explanatory diagram for explaining a schematic structure of a vertical crusher according to the present embodiment. FIG. 2 is a diagram conceptually illustrating a pulverization system using a vertical pulverizer according to this embodiment. 3 is a graph showing the relationship between the air volume and the friction coefficient, FIG. 4 is a graph showing the relationship between the speed of the rotary table and the dynamic friction coefficient, and FIG. 5 is a graph showing the relationship between the frequency ratio and the vibration amplification coefficient.

Hereinafter, the preferable structure of the vertical crusher 1 which concerns on embodiment of this invention is demonstrated.
The vertical crusher 1 used in the present embodiment, as shown in FIG. 1, is a casing 1B that forms the outline of the vertical crusher 1, a rotary table 2, and an upper surface of the rotary table 2 (also referred to as a rotary table upper surface 2A). There are a plurality of conical crushing rollers 3 disposed at positions where the outer peripheral portion is equally divided in the circumferential direction, a speed reducer 2B installed under the vertical crusher 1, and a rotary table via the speed reducer 2B. 2, a variable speed electric motor 2 </ b> M that drives 2, and a control panel 50 that controls the rotational speed of the electric motor 2 </ b> M.

  The crushing roller 3 is connected to the piston rod 9 of the hydraulic cylinder 8 via an upper arm 6 pivotally attached to the lower casing by a shaft 7 and a lower arm 6A formed integrally with the upper arm 6. The hydraulic cylinder 8 is pressed in the direction of the rotary table upper surface 2A by the operation of the hydraulic cylinder 8, and is rotated by being driven by the raw material through the rotary table upper surface 2A.

A separator 14 and a raw material charging port 35 are provided at the center upper portion of the upper surface 2A of the rotary table of the casing 1B, and a raw material charging chute 13 is arranged so as to penetrate the central axis of the separator 14 up and down. Thus, the raw material can be charged (also referred to as supply) from the raw material charging port 35 to the rotary table upper surface 2A via the raw material charging chute 13.
In addition, the separator 14 includes a plurality of blades 14A arranged in a reverse truncated cone shape having a diameter increased upward with the rotation axis of the separator 14 as a center, with a predetermined interval between them, and can be freely operated by a driving device (not shown). It can be rotated.

  The raw material charged from the raw material charging chute 13 is moved to the outer peripheral portion of the rotary table upper surface 2A while drawing a spiral trajectory on the rotary table upper surface 2A, and is bitten by the rotary table upper surface 2A and the pulverizing roller 3 to be pulverized. Then, a part of the raw material caught by the rotary table upper surface 2A and the pulverizing roller 3 passes over the dam ring 15 provided around the outer edge of the rotary table upper surface 2A, and the outer peripheral portion of the rotary table upper surface 2A. It goes to the annular passage 30 (which may be referred to as the annular space 30), which is a gap with the casing. Here, a gas inlet 33 for introducing gas is provided below the rotary table 2 of the casing 1B, and an upper outlet 39 for taking out the raw material pulverized together with the gas is further provided above the rotary table. Provided.

  During operation of the vertical crusher 1, gas (air in the present embodiment) is introduced from the gas inlet 33 to pass through the separator 14 from the lower side of the rotary table in the casing 1B, and the upper outlet. A gas stream flowing to 39 is generated.

The raw material charged into the vertical crusher 1 and a part of the raw material crushed by the rotary table 2 and the crushing roller 3 and over the dam ring 15 are blown up by the gas to rise in the casing, and the rotary separator 14 To reach.
Here, the raw material having a large diameter and a large weight cannot pass through the blades 14A of the separator 14 and falls below the separator 14, is re-engaged by the grinding roller 3, and is pulverized. Then, it passes through the separator 14 through the blades 14 A arranged with a gap, and is taken out from the upper outlet 39.

  Further, a part of the raw material having a maximum particle size that does not get caught in the crushing roller 3 and reaches the annular passage as it is falls from the annular passage 30 to the lower side of the rotary table and passes through the lower take-out port 34 of the vertical crusher 1. It is taken out.

  Of course, the model of the vertical crusher 1 that can be used in the present embodiment is not limited to that described above. For example, the vertical crusher is a tire-type vertical crusher in which the shape of the crushing roller 3 is a spherical shape. 1 may be sufficient. Further, the separator 14 may be a fixed type according to the required particle size of the product.

  Here, in the present embodiment, the lower sensor S1 serves as a gas pressure gauge for measuring the pressure of the gas flowing through the gas inlet 33, and the upper part serves as a gas pressure gauge for measuring the pressure of the gas flowing through the product outlet 39. A sensor S2 and a vibration sensor S3 for measuring the vibration value of the vertical crusher 1 are provided.

Next, the control panel 50 provided in the vertical crusher 1 will be briefly described.
In the embodiment shown in FIG. 1, the control panel 50 includes a calculator 50B that detects a differential pressure by comparing signals from the lower sensor S1 and the upper sensor S2.
In the embodiment shown in FIG. 1, during operation in advance, the differential pressure signal transmitted from the calculator 50B and the vibration value transmitted from the vibration sensor S3 are input, and the vibration value is converted into a vertical crusher. A storage device is provided that records the state of the differential pressure (gas passage resistance) immediately before exceeding the permissible range as a boundary differential pressure pattern.

While controlling the vertical crusher by the control method according to the present embodiment (during control operation), when the boundary differential pressure patterns stored in the computing unit 50B and the storage unit 50C are compared and substantially coincide, And a control device 50A for transmitting a signal for decelerating the rotational speed.
In the embodiment shown in FIG. 1, the electric motor 2M is a variable speed type, and is connected to the rotary table 2 via a speed reducer 2B. Therefore, the electric motor 2M can freely change the rotation speed of the turntable 2 by freely changing the rotation speed according to a signal transmitted from the control device 50A of the control panel 50.

Next, a preferred example of the grinding system according to the present embodiment will be described with reference to FIG.
The pulverization system shown in FIG. 2 includes a vertical pulverizer 1, a raw material hopper 20, a bucket elevator 25, a raw material hopper 21, an exhaust fan 89, and the like.
The raw material stored in the raw material hopper 20 is put into the vertical crusher 1 through the bucket elevator 25 and the raw material hopper 21 and pulverized. The raw material pulverized in the vertical pulverizer 1 is moved upward in the vertical pulverizer 1 by the gas flow from the exhaust fan 89 and taken out from the product outlet 39 to the outside. Among the raw materials charged into the vertical crusher 1, some raw materials that have not been taken out from the product take-out port 39 are taken out from the lower take-out port 34 to the bucket. It is again put into the vertical crusher 1 through the elevator 25 and the raw material hopper 21 and pulverized.

Hereinafter, the control method of the vertical crusher 1 according to the present invention will be described with reference to the first embodiment, focusing on the differences from the prior art.
The vertical crusher 1 used in the first embodiment has three crushing rollers, a table rotation speed of 73 RPM, a crushing roller center diameter D of 0.4 m, and a table diameter T. Is 0.64 m.

  The raw material supplied to the central portion of the rotary table is moved toward the outer peripheral portion of the rotary table 2 by the raw material charging chute 13, and is caught by the rotary table 2 and the pulverizing roller 3 and pulverized.

  A part of the raw material caught by the rotary table 2 and the grinding roller 3 passes over the dam ring 15 provided around the outer edge of the rotary table, and the gap between the outer peripheral portion of the upper surface of the rotary table 2A and the casing 1B. It heads for the annular passage 30 which is.

  During operation of the vertical crusher 1, gas is introduced into the machine by an exhaust fan 89 from a gas inlet 33 provided at the lower part of the crusher, and is provided above the crusher via a rotating separator. It is discharged out of the machine from the outlet. As a result, in the casing 1 </ b> B of the vertical crusher 1, a gas flow is generated from the lower side of the rotary table 2 to the upper side of the rotary separator 14. Therefore, a part of the raw material that has passed over the dam ring 15 and reached the annular passage 30 is blown up by the gas flow and rises in the casing 1B.

  The airflow rising in the casing 1B is influenced by the rotary separator 14 and is an airflow rising while turning. Therefore, among the raw materials blown up by the air current, the raw material having a large diameter and a large weight falls below the casing 1B due to the weight, or deviates from the air current due to centrifugal force generated in the raw material itself due to swirling by the air current. Then, it falls below the casing 1B and cannot pass through the rotary separator 14.

The material that has failed to pass through the rotary separator 14 and circulates in the vertical crusher is again entrapped in the crushing roller 3 and crushed. Alternatively, after dropping from the annular passage to the lower side of the rotary table and taken out from the vertical crusher 1 through the lower outlet, it is charged again from the raw material input port of the mold crusher via a conveyor such as the bucket elevator 25. And then crushed.
The raw material having a small diameter passes between the blades, passes through the rotary separator 14, and is taken out from the upper outlet 39.

Hereinafter, a control method of the vertical crusher 1 will be described.
First, in the first embodiment of the vertical crusher control method according to the present invention, the gas pressure at the gas inlet 33 and the product outlet 39 is measured and calculated by the lower sensor S1 and the upper sensor S2 during operation in advance. While the differential pressure is detected by the machine 50B, the vibration value of the vertical crusher is measured by the vibration sensor S3. Then, the state of the differential pressure immediately before the vibration value exceeds the allowable range of the vertical crusher is recorded in the storage device as a boundary differential pressure pattern.
In other words, in the first embodiment according to the present invention, first, the differential pressure value needs to be stored in the storage device as a boundary differential pressure pattern.
The differential pressure value may be actually measured before the control operation, input as a set value to the control panel before the control operation, and stored in the storage device.

Next, during the control operation of the vertical crusher, the gas pressure at the gas inlet 33 and the product outlet 39 is measured by the lower sensor S1 and the upper sensor S2, and the differential pressure is detected by the calculator 50B. Compare with the stored boundary differential pressure pattern.
During the control operation of the vertical crusher, the differential pressure detected by the calculator 50B (the differential pressure value in the first embodiment) and the stored boundary differential pressure pattern substantially coincide, preferably When the values match, the control device 50A transmits a signal for reducing the rotational speed to the electric motor 2M, thereby reducing the rotational speed of the rotary table and preventing the occurrence of abnormal vibration.

  Here, in the conventional vertical crusher, in order to keep the load of the vertical crusher constant, the differential pressure in the machine is usually measured, and the air volume (the gas flow rate through the casing from below to above) is You are driving in a certain state. The differential pressure here is also called a gas passage resistance, and is a pressure difference between the gas pressure at the gas inlet 33 of the vertical crusher and the gas pressure at the product outlet 39 which is a gas outlet. .

  In general, considering the characteristics of a normal blower used in a vertical pulverizer, when the differential pressure increases, the air volume in the vertical pulverizer 1 decreases. If the air volume is reduced, the classification efficiency of the separator 14 is lowered, and the probability that fine powders that should originally be products are not taken out of the machine is increased. Therefore, the amount of fine powder that does not need to be pulverized is larger than in the prior art and returns to the pulverization roller 3.

  FIG. 4 shows the relationship between the rotational speed of the rotary table and the dynamic friction coefficient (the dynamic friction coefficient between the grinding roller and the raw material). The amount of fine powder that does not need to be ground is larger than the conventional amount and returns to the grinding roller 3. If it comes, the friction coefficient between the grinding | pulverization roller 3 and a raw material will fall, As a result, a slip etc. will arise in a grinding | pulverization part and it will cause the vibration of the vertical mill 1. FIG. 3 shows the relationship between the air volume and the coefficient of friction (dynamic coefficient of friction between the grinding roller and the raw material), which supports the above-described effect.

  For this reason, during the operation of the vertical crusher 1, when the differential pressure is measured and the differential pressure reaches the boundary differential pressure value just before the abnormal vibration stored in advance, the rotary table It is effective in preventing vibration by reducing the rotational speed of 2 and restoring the dynamic friction coefficient between the grinding roller 3 and the raw material. In other words, when the vertical crusher causes abnormal vibration, the differential pressure value often increases and increases, and in order to predict the occurrence of abnormal vibration during operation of the vertical crusher, abnormal vibration It is effective for preventing vibration to predict the vibration during the subsequent operation using the differential pressure value immediately before becoming a boundary differential pressure pattern.

  By the way, the relationship between the vertical crusher vibration and the friction coefficient (dynamic friction coefficient between the crushing roller and the raw material) becomes the starting point of vibration, particularly self-excited vibration, when the friction coefficient decreases. Conventionally, the vertical crusher is operated in a state where the air volume is constant as described above. In this case, in order to keep the load in the vertical pulverizer constant, the differential pressure of the vertical pulverizer is measured, and if the differential pressure becomes higher than the set value, the amount of raw material supplied to the vertical pulverizer To keep the set differential pressure (set vertical grinder load) uniform. However, in this method, since the supply amount is lowered in order to keep the differential pressure at a constant value, the production amount decreases.

  Further, the cause of the increase in the differential pressure may be due to an increase in the amount of raw material circulation in the vertical crusher 1. In order to reduce the circulation amount, it is only necessary to increase the pulverization amount per rotation of the pulverization roller 3, so there is a method of increasing the pulverization force, but if the pulverization force (excitation force) is increased, vertical pulverization is possible. Causes machine vibration.

  In addition to the friction coefficient, the vibration generated in the vertical crusher can be considered as follows.

A displacement amount (A) is obtained by dividing the excitation force by the spring constant.

  As shown in FIG. 5, it can be seen that the ratio varies depending on the ratio of the vibration amplification coefficient M, the vibration frequency (ω), and the vibration frequency (ω0) of the pulverized layer. Normally, in FIG. 5, ω / ω0 is operated at 1.0 or less (= resonance point or less), so the frequency of the pulverized layer (ω0) is not changed (the same particle size is changed in proportion to the product particle size). By reducing the excitation frequency (ω), the vibration amplification coefficient can be reduced.

  Since the vibration frequency (ω) is proportional to the rotation speed of the crushing roller, the vibration frequency can be reduced by changing the table rotation speed to be synchronized. As a result, if the denominator, the inner numerator of the numerator ω / ω0 is lowered, the vibration amplification coefficient decreases, so that the vertical crusher vibration can be suppressed.

  As described above, as a method for suppressing or suppressing vibration, there are a friction coefficient securing method and an excitation frequency control method. What is common to these two methods is the number of rotations of the rotary table, and the capacity of the vertical crusher can be maximized by setting the number of rotations to an appropriate number according to the raw material properties.

  That is, when the differential pressure of the vertical crusher 1 deviates from the set value and increases, if the table rotation number of the rotary table 2 is arbitrarily reduced, the excitation frequency is reduced, and the vibration amplification coefficient is reduced, For example, even if the excitation force is increased, the vibration factor can be eliminated before the vertical crusher vibration is generated.

  Hereinafter, the second embodiment of the operation method and control method of the vertical crusher according to the present invention will be described with a focus on differences from the first embodiment described above.

First, in the second embodiment of the vertical crusher according to the present invention, during operation in advance, the gas pressure at the gas inlet 33 and the product outlet 39 is measured by the lower sensor S1 and the upper sensor S2, and at the calculator 50B. While detecting the differential pressure, the vibration value of the vertical crusher is measured by the vibration sensor S3.
Then, the state of the differential pressure immediately before the vibration value exceeds the allowable range of the vertical grinder is detected as a change in the time axis, detected as a differential pressure waveform, and recorded as a boundary differential pressure pattern.

During the control operation of the vertical crusher, the gas pressure at the gas inlet 33 and the product outlet 39 is measured by the lower sensor S1 and the upper sensor S2, and the differential pressure is detected as a change in the time axis by the calculator 50B. While comparing with the stored boundary differential pressure pattern.
During the control operation of the vertical crusher, when the differential pressure waveform detected by the calculator 50B and the stored boundary differential pressure pattern substantially coincide, preferably coincide with each other, the control device 50A sends the electric motor 2M to the motor 2M. A signal for reducing the rotational speed is transmitted to reduce the rotational speed of the rotary table.

When the vertical crusher causes abnormal vibration, there are many patterns in which the differential pressure rapidly increases and increases, and a large differential pressure may occur in a very short time.
Therefore, in order to predict the occurrence of abnormal vibration during operation of the vertical crusher, the differential pressure waveform immediately before the abnormal vibration is recorded is recorded as a boundary differential pressure pattern, and vibration is predicted during the subsequent operation. This is effective in preventing vibration.

It is a principal part longitudinal cross-sectional view which shows embodiment of the vertical crusher which concerns on this invention. It is a figure which illustrates notionally the crushing system using the vertical crusher concerning this embodiment. It is a graph showing the relationship between an air volume and a friction coefficient. It is a graph showing the relationship between the speed of a rotary table, and a friction coefficient. It is a graph showing the relationship between a frequency ratio and a vibration amplification coefficient.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vertical crusher 2 Rotary table 3 Crushing roller 13 Raw material input chute 14 Rotating separator 15 Dam ring 1B Casing 20 Raw material hopper (for new raw material supply)
21 Raw material hopper 25 Bucket elevator 30 Annular passage 33 Gas inlet 89 Exhaust fan (blower)
34 Lower outlet 35 Raw material inlet 39 Product outlet (upper outlet)
50 control panel 50A control device 50B arithmetic unit 50C storage S1 lower sensor S2 upper sensor S3 vibration sensor

Claims (3)

The raw material supplied to the rotary table with a plurality of freely pulverizing rollers is pulverized between the rotary table and the pulverizing roller, and
In the control method of the vertical pulverizer, the pulverized raw material is blown up by the gas introduced from the gas inlet provided below the rotary table and taken out together with the gas from the product outlet provided above the rotary table.
During operation, the vibration value of the vertical crusher is measured while detecting the differential pressure between the gas inlet and the gas pressure at the product outlet, and immediately before the vibration value exceeds the allowable range of the vertical crusher. Record the differential pressure state at the boundary differential pressure pattern,
A control method for a vertical crusher that decelerates the number of rotations of a rotary table when a differential pressure during control operation coincides with the boundary differential pressure pattern. The method for controlling a vertical crusher according to claim 1, wherein a differential pressure value immediately before the vibration value exceeds an allowable range of the vertical crusher is recorded as a boundary differential pressure pattern. The method for controlling a vertical crusher according to claim 1, wherein a temporal change of the differential pressure immediately before the vibration value exceeds an allowable range of the vertical crusher is recorded as a boundary differential pressure pattern.

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