Deslagging double-sealing device for medium-speed coal mill in coal-fired power plant

Abstract

The utility model relates to a deslagging double-sealing device of a medium-speed coal mill in a coal-fired power plant, belongs to the technical field of sealing, and solves the problems that an existing deslagging sealing device is poor in sealing effect and short in service life. The pebble coal blanking pipe comprises a connecting plate, a guide pipe is arranged at the bottom of the connecting plate on the periphery of the pebble coal blanking pipe, a supporting step extending in the radial direction of the guide pipe is arranged on the outer wall of the bottom of the guide pipe, a sliding pipe capable of moving up and down is slidably installed on the outer wall of the supporting step, and an extrusion step extending in the radial direction of the sliding pipe is arranged on the inner wall of the top of the sliding pipe. A supporting step is arranged at the bottom of the sliding pipe, an upper sealing gasket is arranged on the supporting step, a mounting ring of a hollow structure is arranged at the bottom of the sliding pipe, a lower sealing gasket is arranged at the bottom of the mounting ring, pneumatic actuators are arranged at the two ends of the connecting plate, and the output ends of the pneumatic actuators are detachably connected with the sliding pipe. According to the sealing device, the sealing effect can be effectively improved, and the service life of the sealing device is prolonged.

Description

Technical Field

[0001] The present disclosure relates to the field of sealing technology, and in particular, to a double-sealing device for slag discharge of medium-speed coal mills in coal-fired power plants. Background Art

[0002] At present, most coal-fired power plants adopt the direct pulverized coal injection system for boilers. The main configuration of coal mills is medium-speed coal mills, and the slag discharge and conveying systems all adopt positive pressure, negative pressure, chain plate and manual conveying. However, due to the complex changes in coal quality and operating conditions of coal mills, there are not many successful application experiences for the positive pressure and negative pressure conveying systems; the chain plate conveying occupies a large area and has a high investment cost, so it is also less used. At present, the most widely used method is to use a manual trolley to push and transport to a designated location for centralized conveying. The manual trolley not only plays the role of transporting the pebble coal but also plays the role of storing the pebble coal. Therefore, the sealing between the pebble coal hopper and the coal mill discharge mechanism is particularly important. If the sealing is not good, during the discharge of pebble coal, the positive pressure of the coal mill operation will carry coal ash, which will not only pollute the environment of the boiler house but also pose a risk of fire in the pebble coal hopper. At present, there are various ways to seal, such as using snap-type, inflatable, telescopic and electric lifting sealing devices, all of which have disadvantages such as inconvenient operation, short service life, high energy consumption and poor sealing effect.

[0003] For example, the publication number is: CN210875730, which discloses a sealing device for the pebble coal discharge port of a coal mill, which includes: a first coal discharge pipe, a second coal discharge pipe, a connecting plate and a cylinder; the upper port of the first coal discharge pipe is fixedly connected to the coal outlet of the coal mill; the second coal discharge pipe is sleeved on the first coal discharge pipe and can slide up and down relative to the first coal discharge pipe; a retaining ring is arranged on the inner wall of the second coal discharge pipe, and a pressing ring is arranged at the upper end of the second coal discharge pipe; a sealing material is arranged between the retaining ring and the pressing ring; the connecting plate is arranged at the lower end of the second coal discharge pipe; a through hole is arranged on the connecting plate; one end of the cylinder is hinged to the connecting plate, and the other end is hinged to the coal mill; a sealing ring is arranged on the lower end surface of the connecting plate; the through hole is used to communicate with the coal inlet of the pebble coal hopper correspondingly. Using the present invention can achieve the sealing of coal discharge of the coal mill, improve the environment and reduce the sealing cost.

[0004] For the above-mentioned existing sealing devices for the pebble coal discharge port, the sealing method is to seal by wrapping the coal discharge pipe with a sealing material. During the up and down movement of the connecting plate, the sealing material moves relative to the coal discharge pipe and always maintains the seal. This is a radial sealing method, and the sealing material is easily damaged and has a low service life; and it is only a single-layer sealing structure, and the sealing effect is relatively poor.

[0005] Therefore, it is necessary to design a new double-sealing device for slag discharge of medium-speed coal mills in coal-fired power plants to solve the above-mentioned technical problems. Summary of the Utility Model

[0006] The purpose of the present disclosure is to provide a double-sealing device for slag discharge of medium-speed coal mills in coal-fired power plants, which can effectively improve the sealing effect and extend the service life of the sealing device.

[0007] To achieve the above object, the present disclosure provides a double-sealing device for slag discharge of medium-speed coal mills in coal-fired power plants, including a connecting plate, the connecting plate is installed on one side of the coal mill body, the pebble coal dropping pipe corresponding to the coal mill body penetrates to the bottom surface of the connecting plate, a guiding pipe is provided at the bottom of the connecting plate around the pebble coal dropping pipe, a supporting step extending radially along the outer wall of the bottom of the guiding pipe is provided, a slidable pipe that can move up and down is slidably installed on the outer wall of the supporting step, an extrusion step extending radially along the inner wall of the top of the slidable pipe is provided, the inner side surface of the extrusion step is in fit with the outer wall surface of the guiding pipe, and an upper sealing gasket is provided on the supporting step, a hollow-structured mounting ring is provided at the bottom of the slidable pipe, a lower sealing gasket is provided at the bottom of the mounting ring, the shape and size of the lower sealing gasket are adapted to the shape and size of the top surface of the pebble coal bucket trolley, pneumatic actuators are provided at both ends of the connecting plate, and the output end of the pneumatic actuator is detachably connected to the slidable pipe.

[0008] Optionally, both the upper sealing gasket and the lower sealing gasket are nickel wire graphite packing.

[0009] Optionally, a positioning structure for positioning the pebble coal bucket trolley is further provided on the coal mill body below the connecting plate.

[0010] Optionally, the positioning structure includes a U-shaped frame, the closed end of the U-shaped frame is connected to the coal mill body, the inner wall width of the U-shaped frame is adapted to the width of the pebble coal bucket trolley, and when the end face of the pebble coal bucket trolley is pushed to contact the inner side surface of the closed end of the U-shaped frame, the position of the lower sealing gasket corresponds to the position of the top surface of the pebble coal bucket trolley, and guiding surfaces are provided on the inner walls on both sides of the open end of the U-shaped frame.

[0011] Optionally, a rubber gasket is embedded on the inner side surface of the closed end of the U-shaped frame.

[0012] Optionally, a magnet block is embedded on one side of the rubber gasket facing the open end of the U-shaped frame.

[0013] Optionally, a manual adjustment mechanism for adjusting the lifting of the slidable pipe is further provided between both ends of the connecting plate and the slidable pipe.

[0014] Optionally, the manual adjustment mechanism includes a fixing plate and an adjustment screw. The adjustment screw is threadedly connected to the connecting plate. The fixing plate is installed on the outer side wall of the sliding tube, and a guiding column is rotatably installed at the top of the fixing plate through a bearing. A guiding groove is formed in the adjustment screw, and the guiding column is slidably inserted into the guiding groove. A locking structure for locking the two is detachably provided between the adjustment screw and the guiding column.

[0015] Optionally, the locking structure includes a locking bolt. A radially arranged threaded hole is formed at the bottom of the adjustment screw, and a radially arranged through hole is formed in the lower part of the guiding column. The locking bolt is adapted to the thread of the threaded hole.

[0016] Optionally, insertion holes are formed at both ends of the connecting plate, and the locking bolt is movably inserted into the insertion holes.

[0017] Compared with the prior art, the present utility model has the following advantages:

[0018] 1. For the slag discharge double-sealing device of the present utility model, by squeezing the upper sealing pad on the supporting step through the extrusion step, in an axial sealing manner, it avoids rubbing the sealing pad during the up and down movement of the sliding tube, reduces the wear of the sealing pad, and the double-sealing structure of the upper sealing pad and the lower sealing pad can effectively improve the sealing effect and extend the service life of the sealing device.

[0019] 2. For the slag discharge double-sealing device of the present utility model, by arranging a positioning structure below the connecting plate, when the pebble coal bucket trolley is pushed below the sealing device, it can play a role in positioning it, ensuring that the corresponding lower sealing pad of the sealing device can accurately fit on the top surface of the pebble coal bucket trolley, thereby ensuring the sealing effect.

[0020] 3. For the slag discharge double-sealing device of the present utility model, by arranging manual adjustment mechanisms at both ends of the connecting plate, when the pneumatic actuator fails, the connection between the pneumatic actuator and the sliding tube can be loosened, and then the up and down movement of the sliding tube can be adjusted through the manual adjustment mechanism to ensure the normal operation of the equipment and thus ensure the production efficiency.

[0021] Other features and advantages of the present disclosure will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings are used to provide a further understanding of the present disclosure, and constitute a part of the specification. Together with the following specific implementation, they are used to explain the present disclosure, but do not constitute a limitation to the present disclosure. In the drawings:

[0023] Figure 1 is the front view structural schematic diagram when the present utility model is in use;

[0024] Figure 2 It is an enlarged schematic side view structure of the present utility model;

[0025] Figure 3 is Figure 2 an enlarged schematic view of the structure at position A in

[0026] Figure 4 an enlarged schematic top view structure of the positioning structure in the present utility model.

[0027] Description of the reference numerals

[0028] 1 - connecting plate; 2 - coal mill body; 3 - pebble coal discharge pipe; 4 - guide pipe; 5 - support step; 6 - sliding pipe; 7 - extrusion step; 8 - upper gasket; 9 - mounting ring; 10 - lower gasket; 11 - pebble coal bucket trolley; 12 - pneumatic actuator; 13 - U-shaped frame; 14 - guide surface; 15 - rubber pad; 16 - magnet block; 17 - fixing plate; 18 - adjusting screw; 19 - guide post; 20 - guide groove; 21 - locking bolt; 22 - threaded hole; 23 - through hole; 24 - insertion hole. Specific embodiments

[0029] The following will describe in detail the specific embodiments of the present disclosure with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for the purpose of illustration and explanation of the present disclosure, and are not intended to limit the present disclosure.

[0030] In the present disclosure, unless otherwise stated, the orientation terms such as "inner, outer" refer to the inner and outer relative to the contour of the structure or component itself; "first, second", etc. are only used to distinguish one element from another, and do not have sequence and importance. In addition, the same reference numerals in different reference drawings represent the same elements.

[0031] Refer to Figures 1 to 4As shown in the figure, a double-sealing device for slag discharge of a medium-speed coal mill in a coal-fired power plant according to the present utility model includes a connecting plate 1. The connecting plate 1 is horizontally arranged and installed on one side of the coal mill body 2. The corresponding pebble coal dropping pipe 3 of the coal mill body 2 penetrates to the bottom surface of the connecting plate 1, so that the pebble coal can fall and enter the pebble coal hopper trolley 11. A guide pipe 4 is provided at the bottom of the connecting plate 1 outside the pebble coal dropping pipe 3, that is, the guide pipe 4 surrounds the dropping port of the pebble coal dropping pipe 3, so that the pebble coal needs to pass through the guide pipe 4 to fall. A support step 5 extending radially along the bottom outer wall of the guide pipe 4 is provided. A slidable pipe 6 that can move up and down is slidably installed on the outer wall of the support step 5. An extrusion step 7 extending radially along the top inner wall of the slidable pipe 6 is provided. The inner side surface of the extrusion step 7 is in contact with the outer wall surface of the guide pipe 4. The extrusion step 7 is slidably matched with the guide pipe 4, and the support step 5 is slidably matched with the slidable pipe 6. The upper and lower two-layer guiding structure makes the up and down movement of the slidable pipe 6 more stable. And an upper sealing gasket 8 is provided on the support step 5. The bottom of the slidable pipe 6 is provided with an installation ring 9 with a hollow structure. The pebble coal can fall through the middle space of the installation ring 9. A lower sealing gasket 10 is provided at the bottom of the installation ring 9. The shape and size of the lower sealing gasket 10 are adapted to the shape and size of the top surface of the pebble coal hopper trolley 11, so that a seal is formed after the lower sealing gasket 10 is attached to the top surface of the pebble coal hopper trolley 11. Pneumatic actuators 12 are provided at both ends of the connecting plate 1. The pneumatic actuators 12 are cylinders. The output end of the pneumatic actuator 12 is detachably connected to the slidable pipe 6 to drive the slidable pipe 6 to move up and down. Specifically, the output end of the pneumatic actuator 12 can be connected to the slidable pipe 6 by bolts. A pebble coal discharging valve is also provided on the pebble coal dropping pipe 3. When the high-level alarm of the pebble coal hopper is triggered, the pebble coal discharging valve automatically closes. After confirmation of closing, the pneumatic actuator 12 of the sealing device is started to lift the lower sealing gasket 10 to a set distance. The pebble coal hopper trolley 11 can be manually pulled out and transported to the designated place for centralized discharge of pebble coal. After returning, the pebble coal hopper trolley 11 is pushed back to its original position. The pneumatic actuator 12 of the sealing device is started, and the lower sealing gasket 10 is lowered to the top surface of the pebble coal hopper trolley 11 for sealing. Then the pebble coal discharging valve is opened, and the pebble coal hopper normally stores the pebble coal.

[0032] For the slag discharge double-sealing device of the present utility model, by squeezing the upper sealing gasket 8 on the support step 5 through the extrusion step 7, in an axial sealing manner, it is avoided to friction the sealing gasket during the up and down movement of the slidable pipe 6, reducing the wear of the sealing gasket. And the double-sealing structure of the upper sealing gasket and the lower sealing gasket can effectively improve the sealing effect and extend the service life of the sealing device.

[0033] Preferably, both the upper sealing gasket 8 and the lower sealing gasket 10 are nickel wire graphite packing, which is suitable for dynamic sealing under high temperature and high pressure conditions, further improving the sealing performance and extending the service life.

[0034] Preferably, a positioning structure for positioning the pebble coal bucket trolley 11 is further provided on the coal mill body 2 below the connecting plate 1.

[0035] In the slag discharge double-sealing device of this embodiment, by arranging a positioning structure below the connecting plate 1, when the pebble coal bucket trolley 11 is pushed below the sealing device, it can play a role in positioning it, ensuring that the corresponding lower sealing gasket 10 of the sealing device can accurately fit on the top surface of the pebble coal bucket trolley 11, thereby ensuring the sealing effect.

[0036] Preferably, the positioning structure includes a U-shaped frame 13. Among them, the closed end of the U-shaped frame 13 is connected to the coal mill body 2, and the inner wall width of the U-shaped frame 13 is adapted to the width of the pebble coal bucket trolley 11. After the pebble coal bucket trolley 11 is pushed into the U-shaped frame 13, the two side walls of the pebble coal bucket trolley 11 are in contact with the two inner side walls of the U-shaped frame 13 to form side limits. And when the end face of the pebble coal bucket trolley 11 is pushed to contact the inner side face of the closed end of the U-shaped frame 13, the position of the lower sealing gasket 10 corresponds to the top surface position of the pebble coal bucket trolley 11 to form an end limit. Guide surfaces 14 are provided on the inner walls of both sides of the open end of the U-shaped frame 13, which is more convenient for the pebble coal bucket trolley 11 to be pushed in. The positioning structure of this embodiment uses the U-shaped frame 13 to automatically position the pebble coal bucket trolley 11, with a simpler structure and lower cost.

[0037] Preferably, a rubber pad 15 is embedded on the inner side face of the closed end of the U-shaped frame 13 to play a role in buffering the pebble coal bucket trolley 11.

[0038] Preferably, a magnet block 16 is embedded on one side of the rubber pad 15 facing the open end of the U-shaped frame 13. When the pebble coal bucket trolley 11 is pushed in place, the magnet block 16 can be used to adsorb and fix the trolley. While satisfying the requirement that the pebble coal bucket trolley 11 can be pulled out at any time, it can prevent the problem that the pebble coal bucket trolley 11 shakes when the lower sealing gasket 10 presses down for sealing.

[0039] Preferably, a manual adjustment mechanism for adjusting the lifting of the sliding pipe 6 is further provided between both ends of the connecting plate 1 and the sliding pipe 6.

[0040] In the slag discharge double-sealing device of this embodiment, by arranging a manual adjustment mechanism at both ends of the connecting plate 1, when the pneumatic actuator 12 fails, the connection between the pneumatic actuator 12 and the sliding pipe 6 can be loosened, and then the up and down movement of the sliding pipe 6 can be adjusted through the manual adjustment mechanism to ensure the normal operation of the equipment and thus ensure the production efficiency.

[0041] Preferably, the manual adjustment mechanism includes a fixing plate 17 and an adjustment screw 18. Among them, the adjustment screw 18 is threadedly connected to the connecting plate 1. The fixing plate 17 is installed on the outer side wall of the sliding tube 6. And a guiding column 19 is rotatably installed at the top of the fixing plate 17 through a bearing. A guiding groove 20 is formed in the adjustment screw 18. The guiding column 19 is slidably inserted into the guiding groove 20. A locking structure for locking the adjustment screw 18 and the guiding column 19 is detachably provided between the adjustment screw 18 and the guiding column 19. In this embodiment, the matching structure of the fixing plate 17 and the adjustment screw 18, and the guiding column 19 and the guiding groove 20 is adopted. When the manual adjustment mechanism is in an unused state, the up and down movement of the sliding tube 6 drives the guiding column 19 to move up and down in the guiding groove 20 without being interfered by the adjustment screw 18.

[0042] Preferably, the locking structure includes a locking bolt 21. Among them, a radially arranged threaded hole 22 is formed at the bottom of the adjustment screw 18. A radially arranged through hole 23 is formed in the lower part of the guiding column 19. The locking bolt 21 is adapted to the thread of the threaded hole 22. During actual use, when the pneumatic actuator 12 fails, the locking bolt 21 can be threadedly connected to the threaded hole 22 and pass through the through hole 23 to connect the adjustment screw 18 and the guiding column 19 together. When the adjustment screw 18 is rotated, the guiding column 19, the fixing plate 17, and the sliding tube 6 can be driven to move up and down, realizing the up and down movement of the manual adjustment of the sliding tube 6.

[0043] Preferably, insertion holes 24 are formed at both ends of the connecting plate 1. The locking bolt 21 is movably inserted into the insertion holes 24, which serves to temporarily place the locking bolt 21, facilitating subsequent taking and using and preventing loss.

[0044] The preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings. However, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0045] In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, they can be combined in any suitable manner without conflict. To avoid unnecessary repetition, the present disclosure will not separately describe various possible combination methods.

[0046] In addition, any combination can be made between various different embodiments of the present disclosure as long as it does not violate the idea of the present disclosure, and it should also be regarded as the content disclosed by the present disclosure.

Claims

1. A double sealing device for slag discharge of medium-speed coal mill in coal-fired power plant, characterized in that: The invention comprises a connecting plate, which is installed on one side of the coal mill body, and the pebble coal dropping pipe corresponding to the coal mill body penetrates the bottom surface of the connecting plate, and a guide tube is provided at the bottom of the connecting plate outside the pebble coal dropping pipe, and the bottom outer wall of the guide tube is provided with a supporting step extending along its radial direction, and the outer wall of the supporting step is slidably installed with a sliding tube that can move up and down, and the top inner wall of the sliding tube is provided with an extrusion step extending along its radial direction, and the inner side surface of the extrusion step is fitted with the outer wall surface of the guide tube, and an upper sealing gasket is provided on the supporting step, and a mounting ring of a hollow structure is provided at the bottom of the sliding tube, and a lower sealing gasket is provided at the bottom of the mounting ring, and the shape and size of the lower sealing gasket are adapted to the shape and size of the top surface of the pebble coal hopper trolley, and pneumatic actuators are provided at both ends of the connecting plate, and the output end of the pneumatic actuator is detachably connected to the sliding tube.

2. The slag discharge double sealing device for medium-speed coal mill in coal-fired power plant according to claim 1 is characterized in that: The upper sealing gasket and the lower sealing gasket are both nickel wire graphite packing.

3. The slag discharge double sealing device for medium-speed coal mill in coal-fired power plant according to claim 1 is characterized in that: A positioning structure for positioning the stone coal hopper trolley is also provided on the coal mill body below the connecting plate.

4. The slag discharge double sealing device for medium-speed coal mill in coal-fired power plant according to claim 3 is characterized in that: The positioning structure includes a U-shaped frame, a closed end of the U-shaped frame is connected to the coal mill body, the inner wall width of the U-shaped frame is adapted to the width of the gravel coal hopper trolley, and when the end face of the gravel coal hopper trolley is pushed to contact the inner side face of the closed end of the U-shaped frame, the position of the lower sealing gasket corresponds to the top surface position of the gravel coal hopper trolley, and guide surfaces are provided on the inner walls on both sides of the open end of the U-shaped frame.

5. The slag discharge double sealing device for medium-speed coal mill in coal-fired power plant according to claim 4 is characterized in that: A rubber pad is embedded on the inner side surface of the closed end of the U-shaped frame.

6. The slag discharge double sealing device for medium-speed coal mill in coal-fired power plant according to claim 5, characterized in that: A magnet block is embedded on one side of the rubber pad facing one end of the U-shaped frame opening.

7. The slag discharge double sealing device for medium-speed coal mill in coal-fired power plant according to any one of claims 1 to 6, characterized in that: Manual adjustment mechanisms for adjusting the lifting of the sliding tube are also provided between the two ends of the connecting plate and the sliding tube.

8. The double sealing device for slag discharge of medium-speed coal mill in coal-fired power plant according to claim 7, characterized in that: The manual adjustment mechanism includes a fixed plate and an adjusting screw, the adjusting screw is threadedly connected to the connecting plate, the fixed plate is installed on the outer wall of the sliding tube, and a guide column is rotatably installed on the top of the fixed plate through a bearing, a guide groove is opened in the adjusting screw, and the guide column is slidably inserted in the guide groove, and a detachable locking structure is provided between the adjusting screw and the guide column to lock the two.

9. The slag discharge double sealing device for medium-speed coal mill in coal-fired power plant according to claim 8, characterized in that: The locking structure comprises a locking bolt, a radially arranged threaded hole is formed at the bottom of the adjusting screw, a radially arranged through hole is formed at the lower part of the guide column, and the locking bolt is adapted to the thread of the threaded hole.

10. The slag discharge double sealing device for medium-speed coal mill in coal-fired power plant according to claim 9, characterized in that: Both ends of the connecting plate are provided with plugging holes, and the locking bolts are movably plugged into the plugging holes.

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