Scraper device

Abstract

The invention discloses a scraper device which is installed on the side portion of a milling bowl of a coal mill and comprises a scraper support, a hinge shaft, a scraper body, a torsion spring and a supporting frame, the scraper body comprises a scraper body and a lining plate, the scraper body comprises an upper connecting part and a lower connecting part connected with the upper connecting part, the upper connecting part is provided with an upper hinge hole, one end of the torsion spring is fixed to the supporting frame, and the other end of the torsion spring is fixed to the lining plate. And the other end of the scraper body is fixed on the hinge shaft, so that the scraper body has buffering elasticity relative to the support frame. When pebble coal thrown out by the grinding bowl passes through the impeller device, the pebble coal directly falls into the side machine body due to the large specific gravity of the pebble coal, the scraper device rotating along with the grinding bowl scrapes the pebble coal into a discharging hole in a bottom plate of the side machine body to enter a pebble coal collecting system, and the torsional spring is arranged in the middle of a supporting frame of the scraper device, so that the stress structure is optimized; the situation that the torsional spring is out of position is not prone to occurring when the scraper bears overweight loads, the safety and reliability of equipment operation are enhanced, the forming process of the scraper is simplified, the stress structure is guaranteed, and the abrasion resistance is improved.

Description

Technical Field

[0001] The invention relates to medium-speed coal mill technology, and in particular to a scraper device. Background Art

[0002] At present, the scraper device is an important part of the medium-speed coal mill for discharging pebble coal. It is generally composed of scraper brackets, lining plates, shafts, scrapers, torsion springs, support frames, limit bolts and other parts. It is connected to the grinding bowl and rotates with the grinding bowl. Its function is to scrape the pebble coal and other foreign debris that are not easy to grind into the discharge hole on the bottom plate of the side body of the coal mill after passing through the impeller device into the discharge hole on the bottom plate of the side body, and then enter the pebble coal collection system. Foreign debris is usually composed of coal gangue in the raw coal and coal mining machinery parts. For users, it is beneficial to minimize the amount of these debris entering the coal mill.

[0003] The patent document with application number "CN202211123003.5" discloses a medium-speed coal mill. The medium-speed coal mill conveys coal blocks to the grinding device through the coal drop pipe. The drying device on the coal drop pipe can dry the coal blocks to reduce the difficulty of grinding. After the grinding device grinds the coal blocks into coal powder, the ventilation device blows air upward into the separator. The separator sends the coal powder that meets the requirements to the coal powder outlet after screening, and conveys the coal powder that does not meet the requirements downward to the grinding device for secondary grinding. The turbulence device is arranged between the separator and the grinding device, and can blow air to the coal powder that does not meet the requirements discharged from the separator, so that the coal powder that does not meet the requirements is mixed more evenly. The medium-speed coal mill can reduce the difficulty of grinding and improve the qualified rate of coal powder, reduce the wear and consumption of the grinding device, and also reduce the energy consumption of the grinding device.

[0004] The patent document with application number "CN201910039582.7" discloses a medium-speed coal mill, including an upper shell, an intermediate shell, a lower shell and a driving mechanism, wherein the lower end of the upper shell is connected to the intermediate shell by bolts, the lower end of the intermediate shell is connected to the lower shell by bolts, and the lower shell and the driving mechanism are fixedly installed on the ground foundation by anchor bolts; a conical guide plate is fixedly connected in the upper shell and its cone mouth is arranged downward and passes into the intermediate shell, a drop pipe facing the cone mouth is vertically arranged in the conical guide plate, and a coal powder distributor is arranged on the outer side of the drop pipe at the upper end of the upper shell. The present invention can perform secondary separation on the coal powder until qualified coal powder is obtained, and at the same time, the contact area between the grinding roller and the raw coal is increased, the grinding output is improved, the coal type adaptability is stronger, and the airfoil dynamic wind ring can eliminate the turbulence phenomenon to increase the carrying output, reduce the emission of stone coal, and is beneficial to environmental protection.

[0005] The above patent document, combined with the prior art, reveals that the existing scraper device has the following defects:

[0006] During operation, the pebble coal thrown out of the grinding bowl falls directly into the side body when passing through the impeller device due to its large specific gravity, and is then scraped into the pebble coal collection system by the scraper device. However, in actual operation, the coal quality is often poor, and the pebble coal will increase significantly. The large amount of pebble coal entering the side body will bring challenges to the safe operation of the scraper device, and the overloaded scraper and torsion spring will fail or be damaged from time to time. Summary of the invention

[0007] In order to overcome the deficiencies of the prior art, the present invention provides a scraper device to solve the problem of the scraper device.

[0008] The first aspect of the present invention is to provide a scraper device, which is installed on the side of the grinding bowl of a coal mill, and includes: a scraper bracket, a hinge shaft, a scraper body, a torsion spring, and a support frame. The scraper bracket is fixed to the side of the grinding bowl, and the support frame is fixed to the lower part of the scraper bracket. The scraper body includes a scraper body and a lining plate, and the lining plate is fixed to the lower part of the scraper body. The scraper body includes an upper connecting part and a lower connecting part connected to the upper connecting part. The upper connecting part is provided with an upper hinge hole along the length direction. The hinge shaft passes through the upper hinge hole and the support frame to enable the scraper body to be rotatably installed on the support frame. One end of the torsion spring is fixed to the support frame, and the other end is fixed to the hinge shaft, so that the scraper body has buffering elasticity relative to the support frame.

[0009] In the first aspect of the present invention, as a preferred embodiment, the scraper body further includes a torsion spring limit stopper, and the torsion spring limit stopper is fixed to the scraper body and abuts against the outer side of the torsion spring.

[0010] In the first aspect of the present invention, as a preferred embodiment, the scraper body further includes a reinforcing rib, and the reinforcing rib is located at the junction of the upper connecting portion and the lower connecting portion.

[0011] In the first aspect of the present invention, as a preferred embodiment, the scraper body further includes a balancing weight, a lower portion of the lower connecting portion is provided with a plurality of lower fixing holes, and the balancing weight is fixed to the lower fixing holes.

[0012] In the first aspect of the present invention, as a preferred embodiment, the number of the upper connecting parts is 2, and the two upper connecting parts are connected to the upper part of the lower connecting part.

[0013] In the first aspect of the present invention, as a preferred embodiment, an upper fixing hole for limiting and fixing is provided on the upper hinge hole of the upper connecting part.

[0014] In the first aspect of the present invention, as a preferred embodiment, the scraper device also includes a limiting bolt, which passes through the support frame, and the side of the limiting bolt abuts against the end of the torsion spring so that the torsion spring is limited to the middle of the hinge shaft.

[0015] In the first aspect of the present invention, as a preferred embodiment, the scraper device further includes a tilting component, and the tilting component is arranged on the side of the scraper body.

[0016] In the first aspect of the present invention, as a preferred embodiment, the scraper device further includes a pebble coal discharge assembly, and the pebble coal discharge assembly is arranged at the lower part of the scraper body.

[0017] The second aspect of the present invention provides a medium-speed coal mill grinding bowl assembly, comprising the above-mentioned scraper device, grinding bowl, reducer, separator body, impeller device, and side body, the scraper device is installed on the side of the grinding bowl, the reducer is located at the lower part of the grinding bowl, and the impeller device is arranged at the lower part of the separator body. When the pebble coal thrown out of the grinding bowl passes through the impeller device, it falls directly into the side body due to the large specific gravity of the pebble coal. The scraper device rotating with the grinding bowl scrapes the pebble coal into the discharge hole on the bottom plate of the side body and enters the pebble coal collection system.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The scraper bracket is fixed to the side of the grinding bowl, and the support frame is fixed to the lower part of the scraper bracket. The scraper body includes a scraper body and a lining plate. The lining plate is fixed to the lower part of the scraper body. The scraper body includes an upper connecting part and a lower connecting part connected with the upper connecting part. The upper connecting part is provided with an upper hinge hole along the length direction. The hinge shaft passes through the upper hinge hole and the support frame to enable the scraper body to be rotatably installed on the support frame. One end of the torsion spring is fixed to the support frame, and the other end is fixed to the hinge shaft, so that the scraper body has buffer elasticity relative to the support frame. When the stone coal thrown out of the grinding bowl passes through the impeller device, the stone coal directly falls into the side body due to its large specific gravity. The scraper device rotating with the grinding bowl scrapes the stone coal into the discharge hole on the bottom plate of the side body and enters the stone coal collection system. The torsion spring is arranged in the middle of the scraper device support frame to optimize the force structure, so that it is not easy to cause the torsion spring to be out of position when it is subjected to excessive load, thereby enhancing the safety and reliability of equipment operation, simplifying the scraper forming process, ensuring the force structure, and improving the wear resistance.

[0020] 2. It can efficiently scrape away foreign debris such as stone coal, with high equipment reliability, effectively preventing stone coal accumulation and even explosion accidents caused by scraper device failure;

[0021] 3. Improve the overall strength of the scraper, extend the service life of the scraper, and reduce the frequency of inspection and maintenance of the scraper device;

[0022] 4. Improve the wear resistance of the scraper lining, reduce the replacement frequency of wearing parts, and reduce the operation and maintenance cost of the coal mill;

[0023] 5. The efficient scraping performance avoids the accumulation of stone coal and reduces repeated scraping, thereby reducing the working resistance when the grinding bowl rotates, further reducing the power consumption of the motor, saving energy, reducing consumption and emissions, and improving the comprehensive operating performance of the power plant. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural diagram of the present invention;

[0025] Figure 2 is a side view of the present invention;

[0026] Figure 3 It is a front view of the present invention;

[0027] Figure 4 It is the front view of the scraper body;

[0028] Figure 5 is a side view of the scraper body;

[0029] Figure 6 This is the structural diagram of the liner;

[0030] Figure 7 It is the structural diagram of torsion spring;

[0031] Figure 8 Another structural diagram of a torsion spring.

[0032] In the figure: 101, grinding bowl; 103, speed reducer; 104, separator body; 105, impeller device; 106, side body; 200, scraper device; 10, scraper bracket; 20, hinge shaft; 30, scraper body; 31, scraper body; 311, lower connecting part; 3111, lower fixing hole; 312, upper connecting part; 3121, upper hinge hole; 3122, upper fixing hole; 32, torsion spring limit stop; 33, reinforcing rib; 34, balancing weight; 35, lining plate; 40, torsion spring; 50, support frame; 60, limit bolt; 70, tilting assembly; 90, stone coal discharge assembly. DETAILED DESCRIPTION

[0033] Below, in conjunction with the accompanying drawings and specific embodiments, the invention is further described. It should be noted that, under the premise of no conflict, the various embodiments described below or the various technical features can be arbitrarily combined to form a new embodiment. Except as otherwise specified, the materials and equipment used in this embodiment can be purchased from the market. Examples of the embodiments are shown in the accompanying drawings, in which the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0034] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In the description of the present application, "plurality" means two or more, unless otherwise precisely and specifically specified.

[0035] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "connected", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, or it can be connected through an intermediary medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0036] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0037] like Figure 1-8As shown, a scraper device 200 is installed on the side of the grinding bowl 101 of the coal mill, comprising: a scraper bracket 10, a hinge shaft 20, a scraper body 30, a torsion spring 40, and a support frame 50. The scraper bracket 10 is fixed to the side of the grinding bowl 101, and the support frame 50 is fixed to the lower part of the scraper bracket 10. The scraper body 30 includes a scraper body 31 and a lining plate 35. The lining plate 35 is fixed to the lower part of the scraper body 31. The scraper body 31 includes an upper connecting rod 10, a lower connecting rod 10 and a lower connecting rod 10. A connecting portion 312 and a lower connecting portion 311 connected to the upper connecting portion 312, wherein the upper connecting portion 312 is provided with an upper hinge hole 3121 along the length direction, and the hinge shaft 20 passes through the upper hinge hole 3121 and the support frame 50 so that the scraper body 31 is rotatably installed on the support frame 50, one end of the torsion spring 40 is fixed to the support frame 50, and the other end is fixed to the hinge shaft 20, so that the scraper body 31 has buffering elasticity relative to the support frame 50. When the pebble coal thrown out of the grinding bowl 101 passes through the impeller device 105, it falls directly into the side body 106 due to its large specific gravity. The scraper device 200 rotating with the grinding bowl 101 scrapes the pebble coal into the discharge hole on the bottom plate of the side body 106 and enters the pebble coal collection system. The torsion spring is arranged in the middle of the scraper device support frame to optimize the force structure, so that it is not easy for the torsion spring to be dislocated when it is subjected to excessive load, thereby enhancing the safety and reliability of the equipment operation, simplifying the scraper forming process, ensuring the force structure, and improving the wear resistance.

[0038] Specifically, the foreign debris such as hard-to-grind gravel that falls into the side body area of ​​the coal mill after passing through the impeller device is scraped into the discharge hole on the side body bottom plate and then enters the gravel coal collection system. Foreign debris is usually composed of coal gangue in the raw coal and coal mining machinery parts. For users, it is beneficial to minimize the amount of these debris entering the coal mill.

[0039] In the first aspect of the present invention, as a preferred embodiment, the scraper body 30 further includes a torsion spring limit stopper 32, which is fixed to the scraper body 31 and abuts against the outer side of the torsion spring 40. Specifically, the liner of the present invention adopts a surfacing wear-resistant steel plate with high wear resistance and heat resistance, which effectively improves the reliability and service life of the device.

[0040] It should be noted that the scraper is changed from a casting to a welded part. The rib is a weak link and is prone to breakage when hit. Reinforcement ribs are set here to further increase the bearing capacity and extend the service life of the scraper.

[0041] However, it should be noted that the scraper lining is located at the bottom of the scraper device. The main function of the scraper device is to discharge stones, coal gangue, metal lumps and some extremely difficult to grind debris in the raw coal that are not conducive to combustion out of the side body. The lining can effectively scrape these debris mainly by the lining, and its working temperature is between 300 and 400 ° C. Therefore, the wear resistance and heat resistance of the scraper lining are very high. The lining of the present invention adopts surfacing wear-resistant steel plate, and the wear-resistant layer is mainly chromium alloy. At the same time, other alloy components such as manganese, molybdenum, niobium, nickel, and boron are added. The carbides in the metallographic structure are distributed in a fibrous shape, and the fiber direction is perpendicular to the surface. The carbide content is 40-60%, the microhardness can reach HV1850 or above, and the surface hardness can reach HRC58-65. Alloy carbides have strong stability at high temperatures, maintain a high hardness, and also have good antioxidant properties.

[0042] Specifically, in actual operation, as a preferred embodiment: the scraper bracket is connected to the grinding bowl through six high-strength bolts, and the bolt heads on both sides are spot welded and locked by two round steels; the scraper bracket and the support frame are also connected with 6 high-strength bolts; the scraper is installed on the support frame through the shaft, and the two ends are fastened and limited by hexagonal bolts and retaining rings; the torsion spring is passed through the shaft and installed in the middle of the support frame. After pre-tightening, it is limited by the positioning blocks on the scraper bracket and the scraper. The assembly torsion angle is 45 degrees, and the maximum working torsion angle is 90 degrees; the limiting bolt is installed on the scraper bracket, and cooperates with the positioning block of the scraper to prevent the scraper from swinging in the opposite direction; the liner is installed on the scraper by screws and anti-loosening washers.

[0043] In the first aspect of the present invention, as a preferred embodiment, the scraper body 30 also includes a reinforcing rib 33, and the reinforcing rib 33 is located at the junction of the upper connecting part 312 and the lower connecting part 311. The scraper body 30 also includes a balancing weight 34, and a plurality of lower fixing holes 3111 are provided at the lower part of the lower connecting part 311, and the balancing weight 34 is fixed to the lower fixing holes 3111. Specifically, the scraper is formed by welding technology, and reinforcing ribs are provided on the ribs to prevent breakage when hit. The scraper lining is located at the bottom of the scraper device and is a key part for scraping stone coal. It often encounters stones, coal gangue, metal lumps and some debris that are extremely difficult to grind that are not conducive to combustion during work, and its working temperature is very high, between 300 and 400°C.

[0044] In the first aspect of the present invention, as a preferred embodiment, the number of the upper connecting parts 312 is two, and the two upper connecting parts 312 are connected to the upper part of the lower connecting part 311. The upper hinge hole 3121 of the upper connecting part 312 is provided with an upper fixing hole 3122 for limiting fixation. The scraper device also includes a limiting bolt 60, the limiting bolt 60 passes through the support frame 50, and the side of the limiting bolt 60 abuts against the end of the torsion spring 40 so that the torsion spring 40 is limited to the middle of the hinge shaft 20.

[0045] In the first aspect of the present invention, as a preferred embodiment, the scraper device further includes a tilting component 70, which is arranged on the side of the scraper body 30. The scraper device further includes a pebble coal discharge component 90, which is arranged at the lower part of the scraper body 30. It can efficiently scrape away foreign debris such as pebble coal, has high equipment reliability, and effectively prevents pebble coal accumulation and even explosion accidents caused by equipment failure of the scraper device; improves the overall strength of the scraper, extends the service life of the scraper, and reduces the inspection and maintenance frequency of the scraper device; improves the wear resistance of the scraper lining, reduces the replacement frequency of wearing parts, and reduces the operation and maintenance cost of the coal mill; the efficient scraping performance avoids the accumulation of pebble coal, reduces repeated scraping, thereby reducing the working resistance when the grinding bowl rotates, further reduces the power consumption of the motor, saves energy, reduces consumption and reduces emissions, and improves the comprehensive operation performance of the power plant.

[0046] The second aspect of the present invention provides a medium-speed coal mill grinding bowl assembly, comprising the above-mentioned scraper device, grinding bowl 101, reducer 103, separator body 104, impeller device 105, and side body 106, wherein the scraper device is installed on the side of the grinding bowl 101, the reducer 103 is located at the lower part of the grinding bowl 101, and the impeller device 105 is arranged at the lower part of the separator body 104. When the pebble coal thrown out of the grinding bowl 101 passes through the impeller device 105, it directly falls into the side body 106 due to its large specific gravity. The scraper device 200 rotating with the grinding bowl 101 scrapes the pebble coal into the discharge hole on the bottom plate of the side body 106 and enters the pebble coal collection system.

[0047] It should be noted that the torsion spring is located in the middle of the scraper device support frame. The scraper has been sufficiently strengthened through the above measures, so that it rarely breaks when hit by foreign debris. However, if large foreign debris falls on the bottom of the side body, the torsion spring can help the scraper device to automatically fold and avoid excessive impact, and remove stubborn debris during maintenance. The torsion spring is arranged in the middle of the scraper device support frame, which effectively avoids the problem of torsion spring misalignment and failure when subjected to impact loads, and improves the reliability of equipment operation.

[0048] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A scraper device, installed on the side of the grinding bowl of a coal mill, characterized in that: include: A scraper bracket, a hinge shaft, a scraper body, a torsion spring, and a support frame, wherein the scraper bracket is fixed to the side of the grinding bowl, and the support frame is fixed to the lower part of the scraper bracket, the scraper body includes a scraper body and a lining plate, and the lining plate is fixed to the lower part of the scraper body, the scraper body includes an upper connecting part and a lower connecting part connected with the upper connecting part, and the upper connecting part is provided with an upper hinge hole along the length direction, and the hinge shaft passes through the upper hinge hole and the support frame to enable the scraper body to be rotatably installed on the support frame, one end of the torsion spring is fixed to the support frame, and the other end is fixed to the hinge shaft, so that the scraper body has buffering elasticity relative to the support frame.

2. The scraper device according to claim 1, characterized in that: The scraper body also includes a torsion spring limit stopper, which is fixed to the scraper body and abuts against the outer side of the torsion spring.

3. The scraper device according to claim 2, characterized in that: The scraper body further comprises a reinforcing rib, and the reinforcing rib is located at the junction of the upper connecting portion and the lower connecting portion.

4. The scraper device according to claim 2, characterized in that: The scraper body also includes a balancing weight block, and a plurality of lower fixing holes are provided at the lower portion of the lower connecting portion, and the balancing weight block is fixed to the lower fixing holes.

5. The scraper device according to claim 1, characterized in that: The number of the upper connecting parts is 2, and the two upper connecting parts are connected to the upper part of the lower connecting part.

6. The scraper device according to claim 5, characterized in that: An upper fixing hole for limiting and fixing is provided on the upper hinge hole of the upper connecting part.

7. The scraper device according to claim 1, characterized in that: The scraper device also includes a limiting bolt, which passes through the support frame. The side of the limiting bolt abuts against the end of the torsion spring so that the torsion spring is limited to the middle of the hinge shaft.

8. The scraper device according to claim 1, characterized in that: The scraper device further comprises a tilting assembly, and the tilting assembly is arranged on a side of the scraper body.

9. The scraper device according to claim 1, characterized in that: The scraper device further comprises a pebble coal discharge assembly, and the pebble coal discharge assembly is arranged at the lower part of the scraper body.

10. A grinding bowl assembly for a medium-speed coal mill, characterized in that: It comprises the scraper device, grinding bowl, reducer, separator body, impeller device and side body as described in any one of claims 1 to 9, wherein the scraper device is installed on the side of the grinding bowl, the reducer is located at the lower part of the grinding bowl, the impeller device is arranged at the lower part of the separator body, and the pebble coal thrown out of the grinding bowl directly falls into the side body due to its large specific gravity when passing through the impeller device, and the scraper device rotating with the grinding bowl scrapes the pebble coal into the discharge hole on the bottom plate of the side body and enters the pebble coal collection system.

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