Base of medium-speed coal mill

Abstract

The utility model provides a medium-speed coal mill base, which relates to the technical field of coal mills and comprises a base body, a transmission shaft and two fixing bolts, the outer surface walls of the two fixing bolts are movably sleeved with shells containing a plurality of labyrinth grooves, and the two shells are fixedly connected with the base body through the two fixing bolts respectively. A plurality of sealing rings are arranged on the outer surface wall of the transmission shaft, an air inducing block is arranged on the outer surface wall of each sealing ring, the air inducing blocks move towards a labyrinth groove in the shell along gaps between the air inducing blocks and the shell through a first air inducing opening and a second air inducing opening, and three kinds of air with different air directions can flow into the labyrinth groove under drainage of a drainage block. When the medium-speed coal mill passes through the labyrinth grooves, wind power is mutually offset under the labyrinth grooves, so that the wind power becomes smaller and smaller along with the increase of the times of passing through the labyrinth grooves and is finally completely offset, the sealing effect is improved, and the consumption of the medium-speed coal mill is further avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of coal mills, in particular to a medium-speed coal mill base. Background Technique

[0002] A medium-speed coal mill refers to a coal mill with a working speed of 50-300 r / min, belonging to the professional equipment for the preparation and processing of auxiliary materials for blast furnace ironmaking. The medium-speed coal mill can provide suitable auxiliary materials - pulverized coal for the blast furnace ironmaking system. However, during long-term operation, the transmission shaft of the grinding machine base may have grooves, resulting in a large amount of sealing air leaking from the base seal, and the air pressure in the sealed air chamber cannot be maintained. Therefore, it is particularly important to install a suitable sealing mechanism.

[0003] However, in the prior art, such as the labyrinth lower sealing device of the coal mill base with the patent number "CN113833856A", it includes: the lower frame body of the medium-speed coal mill and the transmission shaft of the medium-speed coal mill. An annular sealing sleeve is sleeved on the transmission shaft of the medium-speed coal mill. The annular sealing sleeve is fixed to the lower frame body of the medium-speed coal mill by bolts. At least two concave labyrinth sealing grooves and at least two concave grooves are axially formed on the inner ring surface of the annular sealing sleeve. A floating sealing ring is arranged at each concave labyrinth sealing groove. The floating sealing ring is fixed to the transmission shaft of the medium-speed coal mill by a tension spring. A flexible sealing strip is fixed in each concave groove. The present invention is used for the labyrinth lower sealing of the coal mill base.

[0004] Although the above patent sleeved the carbon crystal sealing ring on the transmission shaft of the medium-speed coal mill, and the carbon crystal sealing ring has a compensation function in a lap joint manner to ensure that the carbon crystal sealing ring can effectively compensate after wear and maintain the original sealing performance, there are still some deficiencies. For example, the labyrinth channels formed between the concave labyrinth sealing grooves and the floating sealing rings in this device are too monotonous. As a result, even if the leaked air reduces the air pressure through the labyrinth, the reduced efficiency is very low, and multiple labyrinths need to be combined to reduce the wind energy to a certain extent to achieve the sealing effect, which occupies a lot of space. Therefore, a new type of medium-speed coal mill base needs to be proposed. Summary of the Utility Model

[0005] The purpose of the utility model is to solve the problem that the labyrinth channels formed between the concave labyrinth sealing grooves and the floating sealing rings in the prior art are too monotonous, resulting in the fact that even if the leaked air reduces the air pressure through the labyrinth, the reduced efficiency is very low, and multiple labyrinths need to be combined to reduce the wind energy to a certain extent to achieve the sealing effect, which occupies a lot of space. By setting multiple ventilation channels to cancel each other out, the problem raised in the background technique is solved.

[0006] To achieve the above object, the utility model adopts the following technical scheme: A medium-speed coal mill base, comprising: a base body, a transmission shaft and two fixing bolts. The outer walls of the two fixing bolts are both movably sleeved with outer shells containing a plurality of labyrinth grooves, and the two outer shells are respectively fixedly connected to the base body through the two fixing bolts. The outer wall of the transmission shaft is provided with a plurality of sealing rings, and the outer wall of each sealing ring is provided with an air guiding block. The top of each air guiding block is provided with a plurality of first air inlets and second air inlets. The inner wall of each air guiding block is provided with an air guiding slope. One of the outer walls of the two outer shells is provided with a plurality of fixing screw structures, and the two outer shells are fixedly connected through the plurality of fixing screw structures.

[0007] Preferably, a first buffer pad is fixedly installed on the top of each labyrinth groove of the two outer shells to prevent the outer shell from being displaced due to special reasons and colliding with the air guiding block, resulting in damage to the air guiding block.

[0008] Preferably, the outer walls of the two outer shells are both provided with support seats, and the two support seats are fixedly connected through a screw and nut structure. The bottoms of the two support seats are both fixedly installed with support columns to facilitate the support of the outer shell and prevent the position of the outer shell from moving down due to long-term work.

[0009] Preferably, a spring damper is fixedly installed at the bottom of each support column to facilitate the use of the elastic characteristics of the spring damper. When the outer shell moves down under a large wind pressure, the outer shell is reset through the spring damper.

[0010] Preferably, a second buffer pad is fixedly inserted at the top of the two outer shells, and the top of the second buffer pad is in contact with the bottom of the base body, which is convenient for sealing the gap between the outer shell and the base body, and can also prevent direct friction between the outer shell and the base body, resulting in wear.

[0011] Preferably, two flexible sealing rings are fixedly sleeved on the outer wall of the transmission shaft, and the outer walls of the two flexible sealing rings are both in contact with the inner walls of the two outer shells, which is convenient for sealing both the upper half and the lower half of the outer shell, further improving the sealing effect.

[0012] Preferably, the cross-section of each first air inlet is a right trapezoid, and the cross-section of each second air inlet is a parallelogram. By guiding the air flow through the right trapezoid and the parallelogram, the wind direction can be controlled.

[0013] Compared with the prior art, the advantages and positive effects of the utility model are as follows.

[0014] 1. In the present utility model, by providing an air guiding block, whenever there is a leakage of the air pressure in the coal mill, the generated air will move towards the labyrinth grooves in the housing through the first air guiding port, the second air guiding port, and the gap between the air guiding block and the housing. Under the guiding of the guiding block, the three airflows with different directions will cancel each other out under each labyrinth groove. Thus, as the number of times passing through the labyrinth grooves increases, the air pressure will become smaller and smaller until it is completely cancelled out, improving the sealing effect and further avoiding the consumption of the medium-speed coal mill.

[0015] 2. In the present utility model, by providing a support base and a spring damper, it is convenient to support the housing, preventing the housing from descending due to the air pressure generated during long-term sealing, which may lead to a deterioration of the sealing performance. At the same time, a second buffer pad is also provided to prevent the housing from being squeezed by the spring damper against the base body, reducing the service life of the housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a perspective view of the front view structure of a base of a medium-speed coal mill proposed by the present utility model;

[0017] Figure 2 is a perspective view of the internal sectional structure of a base of a medium-speed coal mill proposed by the present utility model;

[0018] Figure 3 is a perspective view of the internal sectional structure of a part of one of the air guiding blocks of a base of a medium-speed coal mill proposed by the present utility model.

[0019] LEGEND: 1. Base body; 2. Transmission shaft; 3. Fixed bolt; 4. Housing; 5. Sealing ring; 6. Air guiding block; 7. First air guiding port; 8. Second air guiding port; 9. Air guiding slope; 10. Fixed screw structure; 11. First buffer pad; 12. Support base; 13. Support column; 14. Spring damper; 15. Second buffer pad; 16. Flexible sealing ring. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] In order to more clearly understand the above-mentioned objects, features, and advantages of the present utility model, the following further describes the present utility model with reference to the drawings and embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments may be combined with each other.

[0021] In the following description, many specific details are set forth to fully understand the present utility model. However, the present utility model may also be implemented in other ways different from those described herein. Therefore, the present utility model is not limited by the specific embodiments disclosed in the following specification.

[0022] Embodiment 1: As Figures 1 - 3As shown in the figure, the utility model provides a medium-speed coal mill base, including: a base body 1, a transmission shaft 2, and two fixing bolts 3. The outer walls of the two fixing bolts 3 are both movably sleeved with a housing 4 containing a plurality of labyrinth grooves, and the two housings 4 are respectively fixedly connected to the base body 1 through the two fixing bolts 3. A plurality of sealing rings 5 are provided on the outer wall of the transmission shaft 2, and a wind guiding block 6 is provided on the outer wall of each sealing ring 5. A plurality of first air inlets 7 and second air inlets 8 are opened at the top of each wind guiding block 6, and a wind guiding slope 9 is opened on the inner wall of each wind guiding block 6. A plurality of fixing screw structures 10 are provided on the outer wall of one of the two housings 4, and the two housings 4 are fixedly connected through the plurality of fixing screw structures 10.

[0023] The effect achieved by the entire embodiment 1 is that by setting the wind guiding block 6, whenever the wind pressure of the coal mill leaks, the generated wind will move towards the labyrinth grooves in the housing 4 through the first air inlet 7, the second air inlet 8, and the gap between the wind guiding block 6 and the housing 4. The three winds with different directions will cancel each other out under the drainage of the drainage block in each labyrinth groove. In this way, as the number of times passing through the labyrinth grooves increases, the wind force will become smaller and smaller, and finally be completely cancelled out, improving the sealing effect and further avoiding the consumption of the medium-speed coal mill.

[0024] Embodiment 2: As Figures 1 - 3 shown in the figure, a first buffer pad 11 is fixedly installed on the top of each labyrinth groove of the two housings 4. Support seats 12 are provided on the outer walls of the two housings 4, and the two support seats 12 are fixedly connected through a screw and nut structure. Support columns 13 are fixedly installed at the bottoms of the two support seats 12, and a spring damper 14 is fixedly installed at the bottom of each support column 13. A second buffer pad 15 is fixedly inserted into the top of the two housings 4, and the top of the second buffer pad 15 is in contact with the bottom of the base body 1. Two flexible sealing rings 16 are fixedly sleeved on the outer wall of the transmission shaft 2, and the outer walls of the two flexible sealing rings 16 are in contact with the inner walls of the two housings 4. The cross-section of each first air inlet 7 is a right trapezoid, and the cross-section of each second air inlet 8 is a parallelogram.

[0025] The effect achieved by the entire embodiment 2 is that by setting the support seats 12 and the spring dampers 14, it is convenient to support the housing 4, preventing the wind force generated by the long-term sealing from causing the housing 4 to drop and resulting in a deterioration of the sealing performance. At the same time, the second buffer pad 15 is also provided to prevent the housing 4 from being squeezed by the spring damper 14 against the base body 1 and reducing the service life of the housing 4.

[0026] The working principle of the whole device is as follows: First, briefly introduce the principle of labyrinth seal. A number of annular seal teeth are arranged in sequence around the rotating shaft. A series of throttling gaps and expansion cavities are formed between the teeth. When the medium to be sealed passes through the gaps of the tortuous labyrinth, a throttling effect is generated to achieve the purpose of leakage prevention.

[0027] When using this sealing device, the air leaked from the coal mill will enter the interior of the outer shell 4 through the gap between the base body 1 and the transmission shaft 2 with the assistance of the seal of the second buffer pad 15. Then it will be divided into three flow directions by the first air inlet 7, the second air inlet 8 and the gap between the air guiding block 6 and the outer shell 4. The air entering from the first air inlet 7 and the second air inlet 8 will produce the first mutual cancellation through the air guiding slope 9 and enter the labyrinth groove inside the outer shell 4. Then it will carry out the second mutual cancellation with the air passing through the gap between the air guiding block 6 and the outer shell 4. The cancelled air will enter the next labyrinth groove and be cancelled again until all the wind force is cancelled, that is, the sealing effect is achieved. In daily sealing, due to the wind pressure moving downward all the time, it is inevitable that the fixing bolts 3 will be loosened and the outer shell 4 will move downward, reducing the sealing effect. At this time, the spring damper 14 under the support seat 12 will use its elastic performance to jack up the outer shell 4 again for support.

[0028] The above is only the preferred embodiment of the present invention, and it is not a limitation to the present invention in other forms. Any person skilled in the art may use the disclosed technical content to make changes or modifications into equivalent embodiments with equivalent changes and apply them to other fields. However, as long as it does not depart from the technical solution content of the present invention, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still belong to the protection scope of the technical solution of the present invention.

Claims

1. A medium speed coal mill base, characterized by: The invention comprises a base body (1), a transmission shaft (2) and two fixing bolts (3), the outer walls of the two fixing bolts (3) are movably sleeved with a shell (4) containing a plurality of labyrinth grooves, and the two shells (4) are respectively fixedly connected to the base body (1) via the two fixing bolts (3), the outer wall of the transmission shaft (2) is provided with a plurality of sealing rings (5), the outer wall of each sealing ring (5) is provided with an air induction block (6), the top of each air induction block (6) is provided with a plurality of first air induction ports (7) and second air induction ports (8), the inner wall of each air induction block (6) is provided with an air induction slope (9), the outer wall of one of the two shells (4) is provided with a plurality of fixing screw structures (10), and the two shells (4) are fixedly connected via the plurality of fixing screw structures (10).

2. A medium speed coal mill base according to claim 1, characterized in that: A first buffer pad (11) is fixedly mounted on the top of each labyrinth groove of the two shells (4).

3. The medium speed coal mill base according to claim 1, characterized in that: The outer walls of the two housings (4) are each provided with a support seat (12), and the two support seats (12) are fixedly connected via a screw-nut structure, and the bottoms of the two support seats (12) are each fixedly mounted with a support column (13).

4. The medium speed coal mill base according to claim 3, characterized in that: A spring damper (14) is fixedly mounted on the bottom of each support column (13).

5. The medium speed coal mill base according to claim 1, characterized in that: A second buffer pad (15) is fixedly inserted on the top of the two shells (4), and the top of the second buffer pad (15) fits the bottom of the base body (1).

6. The medium speed coal mill base according to claim 1, characterized in that: The outer wall of the transmission shaft (2) is fixedly sleeved with two flexible sealing rings (16), and the outer walls of the two flexible sealing rings (16) are both in contact with the inner walls of the two outer shells (4).

7. The medium speed coal mill base according to claim 1, characterized in that: The cross section of each of the first air inlet (7) is a right-angled trapezoid, and the cross section of each of the second air inlet (8) is a parallelogram.

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