JPS6232597Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a material charging device for a vertical roller mill, in particular, a portion of the material to be crushed is reflected below the input end of the charging chute to determine the direction of the charging. By providing a reflective plate for changing the rotation, the material to be crushed from the input chute can be evenly distributed and fed onto the rotary table, making it possible to equalize the crushing performance of each crushing roller, and to avoid rotating parts and narrow spaces. This invention relates to a material charging device for a vertical roller mill that has no parts and is easy to maintain without worrying about breakdowns or clogging of the charging chute.

Generally, vertical mills are used for cement raw materials, clinker,
It is widely used as a device for crushing materials to be crushed, such as slag and coal, into granules or powder. In a vertical mill, the material to be crushed is dropped onto a rotary table inside the casing from an input chute, and the supplied material is pressed against the rotary table and rotated to follow the rotation of the rotary table. It is configured so that the ground material is ground between the rollers and the ground material is blown up by hot gas etc. blown upward from around the rotary table and taken out of the casing.

However, in the past, the raw material (material to be crushed) was fed from one direction onto the rotary table from the input chute, which resulted in excessive supply of raw material to one of the multiple crushing rollers. It has become commonplace. As a result, the following problems arose.

Since the amount of wear of the roller tires attached to each crushing roller is not uniform and the lifespan of the roller tires is different, the roller tires cannot be replaced at the same time, resulting in poor maintenance.

Since too much raw material is supplied to one crushing roller, the biting rate of the raw material deteriorates, leading to a decrease in crushing performance.

Vibration of the crushing roller increases due to excessive supply of raw materials, which adversely affects the bearings that support the crushing roller.

Therefore, it is conceivable to provide a rotary chute or a distributor at the input section at the lower end of the input chute so that the raw materials can be evenly supplied onto the rotary table. However, in the case of a rotating chute, the raw material may enter the rotating support such as a bearing, causing rotational failure, and the device requires a drive means, making the device larger and more complex. There are problems such as chute clogging and the need for a large installation volume.

The present invention was devised to effectively solve the above-mentioned conventional problems, and the purpose of the present invention is to reflect a part of the material to be crushed that is input from the input chute below the input end of the input chute. By providing a reflector that changes the feeding direction, the material to be crushed from the input chute is evenly distributed and supplied onto the rotary table, so that the amount of material to be crushed to be supplied to each crushing roller is uniform. This improves the crushing performance of the crushing rollers, equalizes the wear of the roller tires and allows them to be replaced at the same time, and reduces mill vibration.Moreover, the simple structure and no drive unit prevents clogging of the input chute. To provide a material feeding device for a vertical roller mill which is free from the fear of breakage.

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

In FIG. 1, 1 is a cylindrical casing, and at the bottom of the casing 1 is a rotary table 2.
is horizontally rotatable. As shown in FIGS. 1 and 2, an annular groove 3 is formed on the top surface of the circular rotary table 2, and three crushing rollers 4 are arranged at equal intervals along the groove 3. It is set up. Each crushing roller 4 is rotatably supported by a bracket (not shown) or the like.

Above the rotary table 2, there is an input chute 5, which has a rectangular chute cross section and which supplies powdery materials to be crushed (hereinafter referred to as raw materials) M such as cement raw materials, clinker, slag, and coal. 1 is provided to penetrate through it. The input chute 5 connects its lower input end 5a to the rotary table 2.
It is arranged at a predetermined angle of inclination so as to face the sky.

Reflection plates 6 and 7 are provided below the input end 5a in the input direction of the raw material M to reflect a part of the raw material M input from the input end 5a and change its direction. The reflecting plates 6 and 7 are provided at a predetermined interval in the falling flow path of the raw material M input from the input chute 5, and reflect 1/3 of the amount of raw material input from the input chute 5, respectively. Therefore, the raw material reflection cross-sectional areas of the reflectors 6 and 7 are set so that they each occupy approximately 1/3 of the total falling channel cross-section of the raw material M.

The reflectors 6 and 7 have a rectangular shape, and as shown in FIGS. 3 and 4, support rods 8 and 8 are hung between their upper and lower ends to support the reflectors 6 and 7. At the same time, the support rod 8,
A corner plate 9 is provided between the reflection plate 8 and the reflection plates 6 and 7, respectively. The corner plate 9 defines an angle (hereinafter referred to as a horizontal reflection angle) φ formed by a direction perpendicular to the surfaces of the reflection plates 6 and 7 with respect to the falling flow of the raw material from the input end 5a. Further, in order to fix the reflecting plates 6, 7 supported by the supporting rods 8 and corner plates 9 in the raw material falling channel, a fixed rod is provided between the reflecting plates 6, 7 and the input end 5a of the input chute 5. 10, 10 are interposed. As shown in FIG. 1, the reflectors 6 and 7 are tilted by a predetermined angle θ (hereinafter referred to as vertical reflection angle) from the vertical axis, and the input end 5a and the reflectors 6 and 7 are at an appropriate distance l. are installed separately. The vertical reflection angle θ, the horizontal reflection angle φ, the distance l, and the raw material reflection cross-sectional area of the reflectors 6 and 7 are such that the raw material M input from the input chute 5 is
It is set to be divided into three equal parts in the direction and to be dropped and supplied on the same circumference on the rotary table 2.

Next, the operation of this embodiment will be described.

The raw material M is carried into the input chute 5 from a hopper, a belt conveyor, etc. connected to the upper part of the input chute 5, and the carried raw material M moves through the input chute 5 by its own weight and is transferred from the input end 5a to the rotary table 2. Injected. Among the raw materials input from the input end 5a, the raw material M closer to the right side a in the input direction (1/3 of the total input amount) is reflected by the reflection plate 6 placed in the raw material fall channel, and Its course is turned 120 degrees clockwise in Figure 2, and it is placed in the vicinity of point A. In addition, 1/3 of the total input amount of raw material M input from the center b part of the input end 5a
passes through the space S between the reflection plates 6 and 7, continues as it is, and falls near point B in the center between the crushing rollers 4 and 4. Furthermore, the raw material M, which is 1/3 of the total amount input from the left side c toward the input direction, is
It is reflected by the reflector plate 7, turns its horizontal course by 120 degrees counterclockwise in FIG. 2, and falls near the C contact.

In this way, the raw material M input from the input chute 5 is divided equally into ⅓ in three directions in the center between each of the crushing rollers 4 by the reflecting plates 6 and 7, and divided into A on the same circumference of the rotary table 2. It will be dropped and supplied to three locations: point, point B, and point C. The raw material M, which is equally divided into three parts and supplied onto the rotary table 2, is sent in the circumferential direction of the table 2 by the centrifugal force caused by the rotation of the rotary table 2, and is sent to the crushing roller 4 on the downstream side in the rotational direction of the rotary table 2. Each is crushed at
The raw material M is pulverized between a rotary table 2 and a pulverizing roller 4 that is pressed against the rotary table 2 and rotates following the rotation of the rotary table 2. The pulverized material rises accompanied by the hot gas blown up from the outer periphery of the rotary table 2, is classified by a separator provided on the upper part of the casing 1, and is taken out of the casing 1.

In this way, the raw material M input from the input chute 5 is divided equally into three directions in the center between the respective crushing rollers 4 by the reflection plates 6 and 7, and is then dropped and supplied onto the same circumference of the rotary table 2. Therefore, the amount of raw material M supplied to each grinding roller 4 becomes uniform. Therefore, due to the uneven supply, the raw material M of the crushing roller 4
It is possible to prevent the deterioration of the biting rate and the deterioration of the crushing performance. Further, since the amount of wear of the roller tires of each crushing roller 4 is made uniform and their lifespans are the same, the roller tires can be replaced at the same time and maintenance is good. Furthermore, since the raw material M is uniformly supplied, there is no vibration of the crushing roller 4 due to oversupply, and the vibration load on the bearings etc. that support the crushing roller 4 can be reduced.

Further, since the free-falling raw material M input from the input end 5a is reflected by the reflection plates 6 and 7 at a predetermined distance l from the input end 5a of the input chute 5, the input end 5a is There is no fear of clogging with the raw material M, and since there are no rotating or driving parts, there is no breakdown and ease of maintenance.

In addition, in the above embodiment, the case of a vertical roller mill with three grinding rollers 4 was shown, but when the number of grinding rollers is two or four, the input raw material may be two or more.
A reflecting plate is appropriately installed so that the powder is divided into equal parts or quarters and fed between the grinding rollers. In addition, since it is difficult to accurately estimate the flow of the raw material M moving through the input chute 5 depending on the particle size of the raw material M, the water content, the state of the raw material being carried into the input chute 5, etc., the reflector 6 , 7, the vertical reflection angle θ, the horizontal reflection angle φ, the distance l between the input end 5a and the reflection plates 6 and 7, the raw material reflection cross-sectional area of the reflection plates 6 and 7, etc. established,
It is desirable to be able to adjust these to appropriate values. In addition, in the model experiment of the above-mentioned example, it has been confirmed that the raw material can be divided and charged evenly in three directions regardless of the input amount and falling speed. Furthermore, since the reflection plates 6 and 7 are simply provided below the input end 5a,
It does not take up much installation space and can be provided at low cost.

In summary, according to the present invention, the following excellent effects can be achieved.

(1) A part of the material to be crushed that has been inputted is reflected below the input end of the input chute to change the direction of the input, and the material to be crushed from the input chute is distributed and supplied onto the rotary table. Since the reflecting plate is provided, the amount of material to be crushed to be supplied to each crushing roller can be made uniform, and the crushing performance of the crushing roller can be improved.

(2) Furthermore, since the wear amount of the roller tires of each crushing roller is uniform and their lifespans are the same, the roller tires can be replaced at the same time, making maintenance easier.

(3) Furthermore, since the material to be crushed is uniformly fed, mill vibration can be reduced.

(4) The material to be crushed is uniformly divided by reflecting the free-falling material inputted from the bottom of the input end with a reflector plate, so there is no narrow part in the input chute, and the input chute is free from the materials to be crushed. You don't have to worry about it getting stuck.

(5) Also, since there are no rotating or driving parts, there is no breakdown and ease of maintenance.

(6) It is sufficient to simply provide a reflector, it does not take up much installation space, and it can be manufactured at low cost and is highly practical.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a vertical mill equipped with a charging device according to the present invention, FIG. 2 is a plan view of the same, FIG. 3 is a plan view showing an embodiment of a reflector, and FIG. It is a front view. In the figure, 1 is a casing, 2 is a rotary table, 4
5 is a crushing roller, 5 is an input chute, 6 and 7 are reflecting plates, 8 is a support rod, 9 is a corner plate, 10 is a fixed rod, and M is a raw material (material to be crushed).

Claims (1)

[Scope of utility model registration request] A vertical roller mill comprising a rotary table rotatably supported in a cylindrical casing, and crushing rollers disposed on the rotary table at appropriate intervals along the rotation direction of the rotary table. A charging chute is provided with its input end facing upward to supply the material to be crushed onto the rotary table, and a part of the material to be crushed that is input from this is reflected to the lower part of the input end of the input chute. A material charging device for a vertical roller mill, characterized in that a reflecting plate is provided for changing the direction and dispersing and supplying the material to be crushed from the charging chute onto the rotary table.