Medium-speed coal mill

Abstract

The invention relates to the technical field of coal mills, in particular to a medium-speed coal mill which comprises a machine base, a separator, a driving motor, a millstone, a grinding roller and a transmission device. The transmission device comprises a speed reducer and a transmission disc, the machine base is erected on the speed reducer, and the transmission disc is fixedly connected with the speed reducer. The grinding disc is coaxially and fixedly arranged at the top of the transmission disc; a movable ring is arranged in the circumferential direction of the millstone and is in bolted connection with the millstone, and a connecting piece is fixedly arranged on the circumferential side wall of the millstone; the connecting piece is fixedly connected with the movable ring; the connecting piece comprises a shroud ring and a fastening bolt; the plurality of grinding rollers are distributed on the grinding disc in an array manner; the separator is used for providing raw coal and separating coarse and fine pulverized coal; the connecting piece, the hoop ring and the millstone are connected through the fastening bolt, and the connecting lug is fixedly connected with the inner side wall of the movable ring, so that the connecting strength of the movable ring and the millstone is further enhanced, the situation that the bolt between the movable ring and the millstone is broken under the action of shearing force when the coal mill is frequently started and stopped is conveniently avoided, and the production safety of the coal mill is improved.

Description

Technical Field

[0001] The present application relates to the technical field of coal mills, and in particular to a medium-speed coal mill. Background Art

[0002] Medium-speed coal mill refers to a coal mill with an operating speed of 50 to 300 r / min. It is widely used in pulverizing systems in the power, metallurgy, building materials, chemical and other industries, especially in blast furnace coal injection pulverizing systems that require a large amount of coal.

[0003] When the medium-speed coal mill is working, the raw coal enters the center of the grinding disc through the coal drop pipe, the motor drives the moving disc to rotate through the reducer, and the moving disc drives the grinding disc to rotate synchronously. The raw coal in the center of the grinding disc moves to the edge under the action of centrifugal force, and the grinding roller crushes and grinds the raw coal under the action of hydraulic device or other external force to form coal powder; the ground coal powder is blown from the edge of the grinding disc by hot air and brought into the separator for separation. In the separator, the coal powder that meets the fineness requirements is sent to the boiler for combustion, while the coarse powder that does not meet the requirements returns to the grinding disc for continued grinding until it reaches the qualified fineness.

[0004] In the existing medium-speed coal mill, the moving plate is located on the circumference of the grinding plate, and the moving plate and the grinding plate are directly connected by bolts. When the medium-speed coal mill is working, the moving plate and the grinding plate rotate synchronously. When the coal mill is frequently started and stopped, the bolts between the moving plate and the grinding plate are easily broken under the action of shear force due to inertia, resulting in failure of the connection between the moving plate and the grinding plate, affecting the safety of coal mill production. Summary of the invention

[0005] In order to improve the safety of coal mill production, the present application provides a medium-speed coal mill.

[0006] The medium-speed coal mill provided in this application adopts the following technical solution:

[0007] A medium-speed coal mill comprises: a machine base, a separator, a driving motor, a grinding disc, a grinding roller and a transmission device; the driving motor is used to drive the transmission device to rotate;

[0008] The transmission device includes a reducer and a transmission disc, the machine base is mounted on the reducer, the transmission disc passes through the machine base, and the transmission disc is fixedly connected to the reducer;

[0009] The grinding disc is coaxially fixedly arranged on the top of the transmission disc, and the transmission disc drives the grinding disc to rotate synchronously;

[0010] A moving ring is arranged on the circumference of the grinding disc, the moving ring is arranged coaxially with the grinding disc, and the moving ring is bolted to the grinding disc, and the grinding disc drives the moving ring to rotate synchronously; a connecting piece is fixedly arranged on the circumferential side wall of the grinding disc; the connecting piece is fixedly connected to the moving ring; the connecting piece includes a hoop ring and a fastening bolt, the hoop ring is sleeved on the bottom of the grinding disc, the fastening bolt passes through the hoop ring and is threadedly connected to the side wall of the grinding disc, a plurality of connecting ears are evenly distributed on the circumferential side wall of the hoop ring, the connecting ears are integrally arranged with the hoop ring, and the ends of the connecting ears are fixedly connected to the inner side wall of the moving ring;

[0011] A plurality of grinding roller arrays are distributed on the grinding disc, and the grinding rollers can rotate on the grinding disc;

[0012] The separator is arranged above the grinding disc, and is used to provide raw coal to the grinding disc and separate coarse and fine coal powder.

[0013] By adopting the above technical scheme, the medium-speed coal mill is set up, when grinding the raw coal, the driving motor drives the reducer to rotate, and with the cooperation of the multi-stage gears of the reducer, the output shaft speed of the reducer is reduced, the output shaft of the reducer drives the transmission plate to rotate, the grinding plate rotates synchronously with the transmission plate, and the grinding plate drives the moving plate to rotate. While the grinding plate rotates, the grinding roller is driven by the grinding plate to rotate, and the raw coal falls onto the grinding plate through the separator. When the grinding roller rotates, the raw coal is ground into coal powder with a fineness that meets the combustion requirements; the connecting piece is set, the hoop ring and the grinding plate are connected by fastening bolts, so that the installation and fixation of the hoop ring are realized, and the connecting ears arranged circumferentially on the hoop ring are fixedly connected to the inner side wall of the moving ring, which further enhances the connection strength between the moving ring and the grinding plate, so as to avoid the bolts between the moving plate and the grinding plate from breaking under the action of shear force when the coal mill is frequently started and stopped, thereby improving the safety of coal mill production.

[0014] In a specific embodiment, it further comprises a casing, a receiving tray is coaxially sleeved on the top of the base, the casing is fixedly connected to the top wall of the receiving tray, and the grinding disc, grinding roller and transmission disc are all located in the casing;

[0015] The separator is fixedly arranged on the top of the casing, and a coal dropping pipe is arranged on the separator, and the coal dropping pipe is communicated with the inner cavity of the casing.

[0016] By adopting the above technical solution, the casing and the receiving plate are set to form a sealed space, and the raw coal enters the inner cavity of the casing from the coal drop pipe and falls onto the grinding disc. When the grinding roller grinds the raw coal, the casing protects the grinding disc, grinding roller and transmission disc, thereby preventing dust, moisture and other external factors from entering the coal mill and preventing the internal structure of the coal mill from being damaged.

[0017] In a specific possible implementation, the drive motor is arranged outside the machine base, a coupling is arranged on the output shaft of the drive motor, the coupling passes through the side wall of the machine base, and the coupling is fixedly connected to the input shaft of the reducer.

[0018] By adopting the above technical solution, the output shaft of the driving motor is fixedly connected to the input shaft of the reducer through a coupling. When the coal mill is working, the driving motor drives the reducer to rotate, and the reducer drives the grinding disc to rotate, thereby providing a power source for the coal mill, facilitating the grinding of raw coal.

[0019] In a specific possible implementation scheme, the transmission disc includes an integrally arranged transmission flange and a connecting seat, the connecting seat is coaxially arranged with the transmission flange, and the connecting seat is coaxially fixedly connected with the output shaft of the reducer;

[0020] The grinding disc is coaxially fixedly arranged on the top wall of the transmission flange, and the grinding disc rotates synchronously with the transmission flange.

[0021] By adopting the above technical solution, the transmission plate and the connecting seat are coaxially fixedly connected with the output shaft of the reducer, so that the reducer drives the transmission plate to rotate, thereby causing the grinding plate connected to the transmission plate to rotate; at the same time, the transmission flange provides an installation base for the grinding plate, which facilitates the installation and fixation of the grinding plate.

[0022] In a specific feasible implementation scheme, a hot air inlet is provided on the side wall of the casing, the height of the hot air inlet is lower than the height of the dynamic ring, a plurality of air outlets are provided on the dynamic ring, and the air outlets are evenly distributed along the circumference of the dynamic ring; the hot air inlet is connected to a hot air blower, and the hot air blower is used to blow hot air to the air outlet.

[0023] By adopting the above technical scheme, when the raw coal is ground, the ground coal powder moves to the moving ring on the side of the grinding disc under the action of centrifugal force, and the hot air blower blows hot air to the air outlet arranged on the moving ring, so that the coal powder with small particle size is blown up to the separator for separation, and the coal gangue and pebble coal that are difficult to grind are discharged from the air outlet of the moving ring, so as to prevent the coal gangue and pebble coal from being retained in the casing, thereby damaging the grinding disc and grinding roller and affecting the service life of the coal mill.

[0024] In a specific possible implementation scheme, a scraper is fixedly provided on the bottom wall of the transmission flange, and a plurality of scrapers are evenly distributed along the circumference of the transmission flange, and the scraper rotates synchronously with the transmission flange; the scraper is located between the transmission flange and the receiving tray.

[0025] By adopting the above technical scheme, after the gangue and pebble coal are discharged from the air outlet, they fall onto the receiving plate. When the transmission plate rotates, the transmission flange drives the scraper to rotate synchronously, so that the scraper gathers the pebble coal and the gangue together, making it easier to clean the pebble coal and the gangue.

[0026] In a specific possible implementation mode, a plurality of discharge openings are provided at the edge of the receiving tray, and the plurality of discharge openings are evenly distributed along the circumference of the receiving tray, and the discharge openings are used to discharge coal gangue and pebble coal.

[0027] By adopting the above technical solution, when the scraper rotates, the scraper drives the gangue and pebble coal to move on the receiving plate. When the scraper rotates to the discharge port, the gangue and pebble coal are discharged from the discharge port, thereby preventing the gangue and pebble coal from being retained in the coal mill and causing damage to the components.

[0028] In a specific possible implementation manner, a powder outlet is provided on the separator, and the powder outlet is communicated with the inner cavity of the casing.

[0029] By adopting the above technical solution, a powder outlet is set, and when the hot air blows the coal powder into the separator, the separator separates the coal powder with the required fineness, and the separated coal powder with the required fineness is discharged from the powder outlet, which is convenient for realizing the supply of coal powder required for boiler combustion.

[0030] In summary, the present application includes at least one of the following beneficial technical effects:

[0031] 1. The connecting parts are set up, and the hoop ring and the grinding disc are connected by fastening bolts, so that the installation and fixation of the hoop ring are realized. The connecting ears arranged circumferentially on the hoop ring are fixedly connected to the inner wall of the moving ring, which further enhances the connection strength between the moving ring and the grinding disc, and makes it easy to avoid the bolts between the moving disc and the grinding disc from breaking under the action of shear force when the coal mill is frequently started and stopped, thereby improving the safety of coal mill production.

[0032] 2. After the gangue and pebble coal are discharged from the air outlet, they fall onto the receiving plate. When the transmission plate rotates, the transmission flange drives the scraper to rotate synchronously. While the scraper rotates, the scraper drives the gangue and pebble coal to move on the receiving plate. When the scraper rotates to the drop port, the gangue and pebble coal are discharged from the drop port, which prevents the gangue and pebble coal from being retained in the coal mill and causing damage to parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings are used to provide a further understanding of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation to the present application.

[0034] Figure 1 It is a schematic diagram of the overall structure of a medium-speed coal mill according to an embodiment of the present application.

[0035] Figure 2 yes Figure 1 The enlarged view of part A is intended to illustrate the hot air inlet and outlet.

[0036] Figure 3 yes Figure 2 The enlarged view of part B is intended to illustrate the connecting parts.

[0037] Figure 4 yes Figure 1 The enlarged view of part C is intended to illustrate the blanking opening.

[0038] Description of the drawings: 1. Machine base; 11. Receiving plate; 111. Material outlet; 2. Separator; 21. Coal drop pipe; 22. Powder outlet; 3. Driving motor; 31. Coal coupling; 4. Grinding disc; 41. Moving ring; 411. Air outlet; 42. Connecting piece; 421. Hoop; 4211. Connecting ear; 422. Fastening bolt; 5. Grinding roller; 6. Transmission device; 61. Reducer; 62. Transmission disc; 621. Transmission flange; 6211. Scraper; 622. Connecting seat; 7. Casing; 71. Hot air inlet. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with the drawings in this application. Obviously, the described embodiments are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0040] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; in the description of this application, unless otherwise specified, "plurality" means two or more.

[0041] The following is combined with Figure 1-4 This application is described in further detail.

[0042] The embodiment of the present application discloses a medium-speed coal mill.

[0043] Reference Figure 1A medium-speed coal mill comprises: a machine base 1, a separator 2, a driving motor 3, a grinding disc 4, a grinding roller 5, a transmission device 6 and a casing 7; the machine base 1 is mounted above the transmission device 6, the driving motor 3 passes through the machine base 1 and is fixedly connected to the transmission device 6, a receiving tray 11 is coaxially sleeved on the top wall of the machine base 1, the casing 7 is fixedly connected to the top wall of the receiving tray 11, the grinding disc 4 and the grinding roller 5 are both located in the inner cavity of the casing 7, the separator 2 is arranged on the top of the casing 7, and the separator 2 is communicated with the inner cavity of the casing 7.

[0044] Reference Figure 1 The transmission device 6 includes a reducer 61 and a transmission disc 62. The reducer 61 is arranged below the machine base 1, and the drive motor 3 is arranged outside the machine base 1. A coupling 31 is arranged on the output shaft of the drive motor 3. The coupling 31 passes through the side wall of the machine base 1, and the coupling 31 is fixedly connected to the input shaft of the reducer 61; the transmission disc 62 is fixedly arranged on the top of the reducer 61, the transmission disc 62 passes through the machine base 1, and the transmission disc 62 is fixedly connected to the output shaft of the reducer 61; the grinding disc 4 is coaxially fixedly arranged on the top of the transmission disc 62, and the transmission disc 62 can drive the grinding disc 4 to rotate synchronously; the grinding disc 4 is circumferentially provided with a moving ring 4 1. The moving ring 41 is coaxially arranged with the grinding disc 4, and the moving ring 41 is bolted to the grinding disc 4, and the grinding disc 4 drives the moving ring 41 to rotate synchronously; a plurality of grinding rollers 5 are distributed in an array on the grinding disc 4, and the grinding rollers 5 can rotate on the grinding disc 4; the separator 2 is located above the grinding disc 4, and a coal dropping pipe 21 and a powder outlet 22 are arranged on the separator 2, and the coal dropping pipe 21 and the powder outlet 22 are both connected with the inner cavity of the casing 7, and the raw coal enters the inner cavity of the casing 7 from the coal dropping pipe 21, and falls onto the grinding disc 4 for grinding, and the ground coal powder flows back to the separator 2 again, and the separator 2 separates the coal powder with the required fineness and discharges it through the powder outlet 22.

[0045] Reference Figure 3 A hot air inlet 71 is provided on the side wall of the casing 7, and the height of the hot air inlet 71 is lower than the height of the moving ring 41. A plurality of air outlets 411 are provided on the moving ring 41, and the air outlets 411 are evenly distributed along the circumference of the moving ring 41; the hot air inlet 71 is connected to a hot air blower, and the hot air blower blows hot air to the air outlets 411.

[0046] Reference Figure 3 A connecting piece 42 is fixedly provided on the circumferential side wall of the grinding disc 4; the connecting piece 42 is fixedly connected to the moving ring 41; the connecting piece 42 includes a hoop 421 and a fastening bolt 422, the hoop 421 is sleeved on the bottom of the grinding disc 4, the fastening bolt 422 passes through the hoop 421 and is threadedly connected to the side wall of the grinding disc 4, a plurality of connecting ears 4211 are evenly distributed on the circumferential side wall of the hoop 421, the connecting ears 4211 are integrally arranged with the hoop 421, and the end of the connecting ear 4211 is fixedly connected to the inner wall of the moving ring 41.

[0047] Reference Figure 2 and Figure 4The transmission disc 62 includes an integral transmission flange 621 and a connecting seat 622, the connecting seat 622 is coaxially arranged with the transmission flange 621, and the connecting seat 622 is coaxially fixedly connected with the output shaft of the reducer 61; the grinding disc 4 is coaxially fixedly arranged on the top wall of the transmission flange 621, and the grinding disc 4 rotates synchronously with the transmission flange 621; a scraper 6211 is fixedly arranged on the bottom wall of the transmission flange 621, and a plurality of scrapers 6211 are evenly distributed along the circumference of the transmission flange 621, and the scraper 6211 rotates synchronously with the transmission flange 621, and a plurality of drop openings 111 are opened on the edge of the receiving disc 11, and the plurality of drop openings 111 are evenly distributed along the circumference of the receiving disc 11, and coal gangue and stone coal are discharged through the drop openings 111.

[0048] The implementation principle of a medium-speed coal mill in the present application is as follows: when grinding raw coal, first start the drive motor 3, the output of the drive motor 3 drives the input shaft of the reducer 61 to rotate through the coupling 31, after the multi-stage gear transmission of the reducer 61, the speed is reduced to the working speed range of the coal mill, the output shaft of the reducer 61 drives the transmission disc 62 to rotate, the transmission disc 62 drives the grinding disc 4 to rotate, the grinding roller 5 set on the grinding disc 4 rotates under the drive of the grinding disc 4, and grinds the raw coal falling from the coal drop pipe 21 into powder. In the grinding process, the hot air blower provides hot air to the air outlet 411 of the moving ring 41 through the air inlet, and the hot air forms an ascending rotating airflow, which not only dries the coal powder, but also blows the coal powder with smaller particle size up to the separator 2. After separation by the separator 2, the coal powder with the required fineness is discharged through the powder outlet 22 and sent to the boiler for combustion. Coal gangue and pebble coal with larger particle size fall from the air outlet 411 to the receiving plate 11 due to gravity, and the scraper 6211 rotating with the transmission flange 621 pushes the coal gangue and pebble coal to move on the receiving plate 11. When the coal gangue and pebble coal move to the discharge port, they are discharged from the discharge port to avoid being trapped in the casing 7 and causing damage to the grinding disc 4 and the transmission disc 62.

[0049] During the rotation of the grinding disc 4, the hoop ring 421 is fixed on the peripheral side of the grinding disc 4 by fastening the bolts 422, and the connecting ears 4211 arranged on the peripheral side of the hoop ring 421 fix the movable ring 41 to the hoop ring 421, further enhancing the connection stability between the grinding disc 4 and the movable ring 41, and preventing the bolts between the grinding disc 4 and the movable ring 41 from being affected by inertia and breaking under the action of shear force when the coal mill is frequently started and stopped, thereby affecting the safety of the coal mill.

[0050] The above embodiments are only used to illustrate the technical solution of the present application, but not to limit it. The present application is not limited to the exact structure described above and illustrated in the accompanying drawings, and it cannot be determined that the specific implementation of the present application is limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, various changes and modifications made without departing from the concept of the present application should be deemed to belong to the protection scope of the present application.

Claims

1. A medium speed coal mill, characterized in that: include: A machine base (1), a separator (2), a driving motor (3), a grinding disc (4), a grinding roller (5) and a transmission device (6); the driving motor (3) is used to drive the transmission device (6) to rotate; The transmission device (6) comprises a reducer (61) and a transmission disc (62), the machine base (1) is mounted on the reducer (61), the transmission disc (62) passes through the machine base (1), and the transmission disc (62) is fixedly connected to the reducer (61); The grinding disc (4) is coaxially fixedly arranged on the top of the transmission disc (62), and the transmission disc (62) drives the grinding disc (4) to rotate synchronously; The grinding disc (4) is provided with a moving ring (41) in the circumferential direction. The moving ring (41) is coaxially arranged with the grinding disc (4), and the moving ring (41) is bolted to the grinding disc (4). The grinding disc (4) drives the moving ring (41) to rotate synchronously. A connecting piece (42) is fixedly provided on the circumferential side wall of the grinding disc (4). The connecting piece (42) is fixedly connected to the moving ring (41). The connecting piece (42) comprises a hoop (421) and a fastening screw. The bolt (422) is sleeved on the bottom of the grinding disc (4), the fastening bolt (422) passes through the hoop (421) and is threadedly connected to the side wall of the grinding disc (4), a plurality of connecting ears (4211) are evenly distributed on the circumferential side wall of the hoop (421), the connecting ears (4211) are integrally arranged with the hoop (421), and the end of the connecting ear (4211) is fixedly connected to the inner wall of the moving ring (41); A plurality of grinding rollers (5) are distributed in an array on the grinding disc (4), and the grinding rollers (5) can rotate on the grinding disc (4); The separator (2) is arranged above the grinding disc (4), and the separator (2) is used to provide raw coal to the grinding disc (4) and to separate coarse and fine coal powder.

2. A medium speed coal mill according to claim 1, characterized in that: It also comprises a casing (7), a material receiving plate (11) is coaxially sleeved on the top of the machine base (1), the casing (7) is fixedly connected to the top wall of the material receiving plate (11), and the grinding disc (4), the grinding roller (5) and the transmission disc (62) are all located in the casing (7); The separator (2) is fixedly arranged on the top of the casing (7), and a coal dropping pipe (21) is arranged on the separator (2), and the coal dropping pipe (21) is communicated with the inner cavity of the casing (7).

3. A medium speed coal mill according to claim 1, characterized in that: The drive motor (3) is arranged outside the machine base (1); a coupling (31) is arranged on the output shaft of the drive motor (3); the coupling (31) passes through the side wall of the machine base (1); and the coupling (31) is fixedly connected to the input shaft of the reducer (61).

4. A medium speed coal mill according to claim 3, characterized in that: The transmission plate (62) comprises an integrally arranged transmission flange (621) and a connecting seat (622), wherein the connecting seat (622) is coaxially arranged with the transmission flange (621), and the connecting seat (622) is coaxially fixedly connected with the output shaft of the reducer (61); The grinding disc (4) is coaxially fixedly arranged on the top wall of the transmission flange (621), and the grinding disc (4) and the transmission flange (621) rotate synchronously.

5. The medium speed coal mill according to claim 1, characterized in that: A hot air inlet (71) is provided on the side wall of the casing (7); the height of the hot air inlet (71) is lower than the height of the moving ring (41); a plurality of air outlets (411) are provided on the moving ring (41); the plurality of air outlets (411) are evenly distributed along the circumference of the moving ring (41); the hot air inlet (71) is connected to a hot air blower, and the hot air blower is used to blow hot air toward the air outlet (411).

6. A medium speed coal mill according to claim 4, characterized in that: A scraper (6211) is fixedly provided on the bottom wall of the transmission flange (621), and a plurality of scrapers (6211) are evenly distributed along the circumference of the transmission flange (621), and the scraper (6211) rotates synchronously with the transmission flange (621).

7. A medium speed coal mill according to claim 2, characterized in that: The edge of the receiving tray (11) is provided with a plurality of discharge openings (111), and the plurality of discharge openings (111) are evenly distributed along the circumference of the receiving tray (11), and the discharge openings (111) are used to discharge coal gangue and pebble coal.

8. The medium speed coal mill according to claim 1, characterized in that: The separator (2) is provided with a powder outlet (22), and the powder outlet (22) is communicated with the inner cavity of the casing (7).

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