JP2815083B2 - Vertical crusher - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a raw material for cement, limestone, slag,
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical pulverizer for pulverizing raw materials such as clinkers, ceramics, and chemicals, and more particularly to a vertical pulverizer that suppresses vibration generated during pulverization in a fine pulverization area and improves productivity.

[0002]

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

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 hot air duct 20, and the gas is introduced into an annular space between the outer peripheral surface of the turntable 3A and the inner peripheral surface of the casing. By being blown up from the crushed fine powder, the crushed fine powder rises in the casing 15 accompanied by the gas, and is subjected to a classifying action by the blade 13A of the separator 13 located at the upper portion. And sent to the next process.

[0006] The conventional vertical pulverizer as described above, especially for those intended for medium pulverization such as in the case of pulverizing cement raw materials or coal, has various dimensions of the pulverizing roller in order to maximize the pulverizing ability. The original (roller average diameter and roller width) are designed and determined with the target of the maximum dimension that can be arranged on the rotary table. The roller average diameter d is d = (0.70 ~
0.85) For D, 3 rollers, d = (0.55-55
0.70) D, d = (0.40-0.40) for 4 rollers
0.55) D was selected. That is, of the numerical range of the average roller diameter d described above, the upper limit value is set based on the geometrical limit in the table layout, and the lower limit value is smaller than the grinding capacity required by the customer. This shows the limit of reducing the average diameter of the rollers and reducing the cost of equipment when the standard capacity of the vertical crusher of the model number is large.

[0007]

However, when such a conventional vertical pulverizer performs pulverization in a fine pulverization area having a smaller product particle size than in a medium pulverization area, the raw material is caught in the pulverizing roller. Efficiency is reduced and abnormal vibration of the mill is generated, so that stable operation cannot be continued.
The grinding ability was also reduced.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems and to provide a vertical pulverizer having a high pulverizing ability with little abnormal vibration even in a fine pulverizing area, the present invention employs an upper surface of an outer peripheral portion of a rotary table. A plurality of rotatable crushing rollers are arranged on the rotary table, and a raw material supplied through a raw material charging chute hanging above the center of the rotary table is applied with a predetermined crushing pressure to the crushing roller so that the upper surface of the rotary table and the peripheral surface of the crushing roller are fixed. The ratio of the average diameter of the crushing roller to the diameter of the rotary table is 0.25 to 0.75 for two rollers, and 0.2 to 0.73 for three rollers.
0 to 0.55, and 0.15 to 0.
45 and the width of the crushing roller was formed to be 0.14 times the diameter of the rotary table.

[0009]

In the vertical crusher of the present invention, crushing is performed by using a crushing roller having a smaller diameter and a smaller width than that of the conventional standard roller, so that the raw material biting upstream of the crushing roller is improved, and the crushing roller is improved. , The abnormal vibration of the mill is drastically reduced, and stable continuous operation is continued. In addition, as a result of achieving a stable and continuous pulverization state with less vibration, the pulverization ability also maintains a relatively high value.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an explanatory diagram for comparing the dimensions of the crushing rollers of the present invention and the conventional example, and FIG. The conventional vertical crusher 1 equipped with standard rollers crushes cement raw materials, limestone, etc. to, for example, about 88 μR 10 to 15%. Is intended.

In other words, the numerical range of the average roller diameter d ₁ of the conventional standard roller is determined based on the geometrical maximum value at which the upper limit value can be arranged on the rotary table, and the lower limit value is determined by the pulverizer of the designated model number. If the capacity is larger than the required capacity of the customer, there is a limit to reduce the cost of equipment by reducing the average diameter of the crushing roller within the range that satisfies the required capacity of the customer. The initial costs of related equipment such as roller bearings, swing arms, and arm bearings can be significantly reduced.

On the other hand, the vertical pulverizer 1 according to the present invention aims at a fine pulverization region in which a product particle diameter is smaller than that of a medium pulverization region.
Or a 500cm ² / g or more of grinding, 7000cm ²
When producing charcoal with a specific surface area of / g or more, the vertical pulverizer with the above-mentioned standard rollers frequently causes abnormal vibrations in the mill, hindering continuous stable operation and lowering the efficiency of raw material biting. The purpose of this study was to solve the problems such as reduced grinding capacity due to the crushing roller. The test results obtained by variously changing
The dimensional area to obtain relatively high crushing ability was grasped. As a result, as shown in FIG. 1, the crushing roller 4 of the present invention has a smaller average diameter d ₂ and a smaller width b ₂ for the _two , three and four rollers than the conventional crushing roller (standard roller). The average diameter d ₂ is 0.25 to 0.70 for two rollers, 0.20 to 0.55 for three rollers, and 0.15 to 0.45 for four rollers with respect to the rotary table diameter D.
Is the ratio of The roller width b is 0.19 times the diameter D of the rotary table in the related art, but is 0.14 times in the present invention.

When the average roller diameter of the present invention is compared with the conventional standard roller, the average roller diameter d ₂ of the present invention is 2
Roller, third roller, all four rollers maximum value of the numerical range approximates the average lower limit of the diameter d ₁ of the standard roller, the minimum value is about 35% of the maximum value. Also, standard roller average ratio of the diameter d ₁ of the small-diameter roller mean diameter d _2, i.e., the small-diameter ratio R, as shown in FIG. 1, from 0.36 to 0.
82, the optimum point where the vibration is particularly small and the pulverizing ability is high in this region is about 0.75, and the vibration has a single amplitude of 10 to 20 μm.
It was also found that the crushing ability was 1.4 to 1.5 times that of the standard roller due to the low vibration. The roller width b _2, employing 75% of 0.14D standard roller b ₁ in consideration of this point.

Considering the reason why the small-diameter roller employed in the present invention is preferable in the fine pulverizing region, FIG.
As shown in the figure, the raw material bite angle θ on the raw material bite side of the grinding roller
In general, the smaller the diameter of the roller, the larger the diameter of the roller compared to the diameter of the roller. Therefore, the raw material once caught in the grinding roller is less likely to escape to the upstream side of the grinding roller due to the rolling force of the grinding roller.
It is considered that the biting efficiency is improved by that much, and the vertical movement of the crushing roller is reduced, so that the vibration is reduced and the crushing ability is also improved. If the average diameter of the crushing roller is too small, the crushing projected area is substantially reduced even if the biting angle θ is increased, so that the crushing ability is reduced at a certain area as a boundary. It is believed that the minimum value in the numerical range described above indicates this boundary.

As described above, in the vertical pulverizer of the present invention, a pulverizing roller having an average diameter and a roller width suitable for the pulverizing area is employed based on various test results. This makes it possible to exhibit relatively high crushing ability with less abnormal vibration.

[0016]

As described above, in the vertical pulverizer of the present invention, stable and continuous operation without abnormal vibration is continued for pulverization in the fine pulverization region, and a relatively high pulverization ability can be obtained. Also, the initial cost can be reduced by reducing the size of the crushing roller.

[Brief description of the drawings]

FIG. 1 is an explanatory view for comparing dimensions of a pulverizing roller of the present invention and a conventional example.

FIG. 2 is a comparative explanatory diagram of the raw material bite angles of the present invention and a conventional pulverizing roller.

FIG. 3 is an overall vertical sectional view of a conventional vertical crusher.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Vertical grinder 3A Rotary table 4 Crush roller 5 Arm 6 Shaft 7 Arm 9 Hydraulic cylinder D Rotary table diameter d Average crush roller diameter d ₁ Average crush roller diameter (standard roller) d ₂ Average crush roller diameter (small diameter roller) b Crush roller width b ₁ Crush roller width (standard roller) b ₂ Crush roller width (small diameter roller) R Small diameter ratio

Claims (1)

(57) [Claims] A plurality of rotatable crushing rollers are disposed on an upper surface of an outer peripheral portion of a rotary table, and a raw material supplied through a material input chute hanging above a center portion of the rotary table is supplied with a predetermined crushing pressure to the crushing roller. In a vertical crusher that gives and crushes between the upper surface of the rotary table and the peripheral surface of the crushing roller,
The ratio of the average diameter of the crushing roller to the diameter of the rotary table is 0.25 to 0.75 for two rollers,
0.25 to 0.55 for three rollers, 0.15 to 0.45 for four rollers, and the width of the crushing roller is 0.14 times the rotary table diameter. Vertical crusher.