A grate top rod sealing structure

Abstract

The present application discloses a grate top rod sealing structure, which relates to the technical field of boilers. The grate top rod sealing structure comprises a stuffing box mounted on the top rod, wherein the first end of the stuffing box is connected to a gland through a first fastener; the gland is provided with a protrusion extending into the sealed space between the inner wall of the stuffing box and the top rod, the inner wall of the second end of the stuffing box is provided with a limiting portion, and a packing stuffing clamped by the protrusion and the limiting portion is provided in the sealed space; the second end of the stuffing box is sealed and connected to a mounting plate through an expansion joint, and the mounting plate is used to be fixed to the outside of the furnace shell, and an insulating material is provided in the insulating space enclosed by the stuffing box, the expansion joint, the mounting plate and the top rod. Compared with the prior art, the sealing effect of the present application is better. If air leakage occurs during the operation of the boiler, the sealing performance of the sealing structure can be adjusted at any time without waiting for the boiler to be shut down for inspection and replacement, thereby ensuring the safe, stable operation and economy of the boiler.

Description

Technical Field

[0001] The present application relates to the technical field of boilers, and in particular to a grate top rod sealing structure. Background Art

[0002] Boiler is an important equipment in biomass power generation project. Boiler air leakage will lead to increased exhaust volume, higher exhaust temperature, greater exhaust heat loss, more wear of heating surface, lower boiler efficiency, increased induced draft fan output, and increased power consumption, which will seriously affect the safe, stable operation and economy of the boiler.

[0003] The grate top rod of the boiler is a device that drives the grate in the furnace. The quality of the sealing structure between the top rod and the furnace shell directly affects the air leakage of the boiler. At present, the top rod and the furnace shell are often sealed with a split graphite carbon ring.

[0004] However, the existing sealing structure has the following disadvantages: 1. The material of the split graphite carbon ring is relatively hard, and its fit with the push rod is poor. When the furnace pressure is unstable, it is easy to cause air leakage and ash leakage; 2. When the push rod moves radially, the floating property of the split graphite carbon ring is general, and the split graphite carbon ring is greatly worn when the push rod reciprocates. Long-term operation will not ensure the sealing, causing air leakage and ash leakage; 3. The sealing gap cannot be adjusted after the sealing structure is installed. If adjustment is required, the split graphite carbon ring needs to be disassembled as a whole to check the status of the split graphite carbon ring; if air leakage occurs during the operation of the boiler, it cannot be adjusted, and it can only be checked and replaced after the boiler is shut down, which seriously affects the safe, stable operation and economy of the boiler. Therefore, the sealing effect of the existing push rod sealing structure is poor. Utility Model Content

[0005] The purpose of the present application is to provide a grate top rod sealing structure to solve the problem of poor sealing effect of the existing sealing structure.

[0006] The technical solution adopted by the present application to solve its technical problems is: a grate top rod sealing structure, including a stuffing box mounted on the top rod, the first end of the stuffing box is connected to the pressure cover by a first fastener; the pressure cover is provided with a protrusion extending into the sealing space between the inner wall of the stuffing box and the top rod, the inner wall of the second end of the stuffing box is provided with a limiting portion, and a packing filler clamped by the protrusion and the limiting portion is provided in the sealing space; the second end of the stuffing box is sealingly connected to a mounting plate through an expansion joint, the mounting plate is used to be fixed to the outside of the furnace shell, and the insulating space enclosed by the stuffing box, the expansion joint, the mounting plate and the top rod is provided with insulating material.

[0007] Furthermore, the first fastener comprises a first bolt, and a rod portion of the first bolt passes through the gland and is threadedly connected to the stuffing box.

[0008] Furthermore, the first fastener also includes a first nut, which is disposed between the gland and the stuffing box and is threadedly connected to the stem of the first bolt.

[0009] Furthermore, the stuffing box and the limiting portion are an integrally formed structure.

[0010] Furthermore, the first end of the expansion joint is overlapped on the outer surface of the second end of the stuffing box and is fixed by a first pipe clamp.

[0011] Furthermore, the mounting plate is provided with an extension portion extending toward the expansion joint, and the second end of the expansion joint is overlapped on the extension portion and fixed by a second pipe clamp.

[0012] Furthermore, a first gasket is provided between the packing filler and the protruding portion, and a second gasket is provided between the packing filler and the limiting portion.

[0013] Furthermore, a third gasket is provided between the thermal insulation material and the mounting plate.

[0014] Furthermore, the first end of the stuffing box is connected to the mounting plate via a movable component so that the stuffing box can swing in the radial direction.

[0015] Furthermore, the movable assembly includes two connecting rods arranged in parallel on the upper and lower sides of the stuffing box, and the two ends of the connecting rods are respectively hinged to the first end of the stuffing box and the mounting plate.

[0016] Beneficial effects of this application:

[0017] The grate top rod sealing structure provided in the embodiment of the present application utilizes the softness of the packing to make the packing filler and the top rod fit more closely, which is not only not easy to leak air and powder when the furnace pressure is unstable, but also consumes less packing filler when the top rod reciprocates, and can ensure the sealing performance for a long time; when fly ash leakage is found in daily inspection, the first fastener can be adjusted externally to make the gland close to the stuffing box, and then the protrusion on the gland can be used to compress the packing filler again to seal it. Therefore, compared with the prior art, the sealing effect of the present application is better. If air leakage occurs during the operation of the boiler, the sealing performance of the sealing structure outside the boiler can be adjusted at any time, without waiting for the boiler to be shut down for inspection and replacement, thereby ensuring the safe, stable operation and economy of the boiler. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a schematic diagram of the grate top rod sealing structure provided in an embodiment of the present application.

[0020] Reference numerals:

[0021] 10-top rod; 11-stuffing box; 12-first fastener; 121-first bolt; 122-first nut; 13-pressure cover; 14-sealed space; 15-protrusion; 16-limiting part; 17-packing; 18-expansion joint; 19-mounting plate; 20-furnace shell; 21-insulating space; 22-insulating material; 23-first pipe clamp; 24-extension part; 25-second pipe clamp; 26-first liner; 27-second liner; 28-third liner; 29-movable assembly; 291-connecting rod; 292-first ear plate; 293-second ear plate. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0023] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In addition, the embodiments and features in the embodiments of this application can be combined with each other without conflict.

[0024] In the description of the embodiments of the present application, the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, or is the orientation or positional relationship in which the product of the application is usually placed when in use, or is the orientation or positional relationship commonly understood by those skilled in the art. The terms "disposed", "opened", "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, and an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal connection of two elements.

[0025] See also Figure 1A grate top rod sealing structure provided in an embodiment of the present application includes a stuffing box 11 sleeved on the top rod 10, and the first end of the stuffing box 11 is connected to the pressure cover 13 through a first fastener 12; the pressure cover 13 is provided with a protrusion 15 extending into a sealed space 14 between the inner wall of the stuffing box 11 and the top rod 10, and the inner wall of the second end of the stuffing box 11 is provided with a limiting portion 16, and a packing filler 17 clamped by the protrusion 15 and the limiting portion 16 is provided in the sealed space 14; the second end of the stuffing box 11 is sealed and connected to a mounting plate 19 through an expansion joint 18, and the mounting plate 19 is used to be fixed to the outside of the furnace shell 20, and an insulating material 22 is provided in an insulating space 21 enclosed by the stuffing box 11, the expansion joint 18, the mounting plate 19 and the top rod 10.

[0026] See also Figure 1 The push rod 10 penetrates the furnace shell 20 of the boiler and extends from the outside of the furnace shell 20 to the inside of the furnace shell 20. The stuffing box 11 is cylindrical and is mounted on the push rod 10 to form a cylindrical sealed space 14 between the stuffing box 11 and the push rod 10. In order to form a necessary and sufficient sealed space 14 between the stuffing box 11 and the push rod 10 so as to facilitate filling of stuffing, the inner diameter of the stuffing box 11 should be appropriately set according to the outer diameter of the push rod 10 during design.

[0027] A gland 13 which is a separate structure from the stuffing box 11 is provided on the left side of the stuffing box 11. The gland 13 is annular and is mounted on the push rod 10. The right end of the gland 13 has a protrusion 15 extending to the right along the axial direction of the push rod 10. The protrusion 15 is cylindrical and can extend into the sealed space 14. Exemplarily, the gland 13 and the protrusion 15 are an integrally formed structure. Of course, in other embodiments, the gland 13 and the protrusion 15 can also be welded. The gland 13 is connected to the stuffing box 11 through a first fastener 12. When the first fastener 12 is tightened, the protrusion 15 of the gland 13 can be axially moved along the inner surface of the stuffing box 11. A limiting portion 16 is fixed at the right end of the inner surface of the stuffing box 11. The limiting portion 16 is annular and is mounted on the push rod 10 to limit the right end of the sealed space 14. Exemplarily, the stuffing box 11 and the limiting portion 16 are an integrally formed structure. Of course, in other embodiments, the stuffing box 11 and the limiting portion 16 may also be connected by welding.

[0028] In the cylindrical sealing space 14, a plurality of packings 17 are arranged side by side along the axial direction of the mandrel 10, and the plurality of packings 17 are clamped by the protrusion 15 and the limiter 16 along the axial direction of the mandrel 10. For example, four packings 17 are arranged in the sealing space 14. During operation, by tightening the first fastener 12, the protrusion 15 of the gland 13 is driven to move rightward to push the packing 17, so as to increase the contact pressure of the packing 17 on the mandrel 10 and the stuffing box 11, and improve the sealing performance.

[0029] A mounting plate 19 is provided on the right side of the stuffing box 11. The mounting plate 19 is annular and is mounted on the top rod 10. The mounting plate 19 is used to be sealed and fixed to the outside of the furnace shell 20 through bolts and other fasteners. The right end of the stuffing box 11 is sealed and connected to the mounting plate 19 through an expansion joint 18 mounted on the top rod 10, so that the expansion joint 18 can be used to compensate for the axial deformation of the sealing structure. A roughly annular insulating space 21 is formed between the stuffing box 11, the expansion joint 18, the mounting plate 19 and the top rod 10. The insulating space 21 is filled with insulating material 22, thereby forming an insulating layer to prevent the heat inside the furnace shell 20 from being transferred to the outside through the sealing structure, thereby achieving the purpose of reducing energy consumption.

[0030] The grate top rod sealing structure provided in the embodiment of the present application utilizes the softness of the packing to make the packing filler 17 and the top rod 10 more closely fitted, which is not only not easy to leak air and powder when the furnace pressure is unstable, but also consumes less packing filler 17 when the top rod 10 reciprocates, and can ensure the sealing performance for a long time; when fly ash leakage is found in daily inspection, the first fastener 12 can be adjusted externally to make the pressure cover 13 close to the stuffing box 11, and then the protrusion 15 on the pressure cover 13 is used to press the packing filler 17 again to seal it. Therefore, compared with the prior art, the sealing effect of the present application is better. If air leakage occurs during the operation of the boiler, the sealing performance of the sealing structure can be adjusted at any time outside the boiler, without waiting for the boiler to be shut down for inspection and replacement, thereby ensuring the safe, stable operation and economy of the boiler.

[0031] In some embodiments, see Figure 1 The first fastener 12 includes a first bolt 121, and the stem of the first bolt 121 passes through the gland 13 and is threadedly connected to the stuffing box 11. Exemplarily, a plurality of first through holes for the first bolts 121 to pass through are evenly arranged along the circumferential direction of the gland 13, and a first internal threaded hole threadedly connected to the first bolt 121 is arranged at a position opposite to each first through hole on the stuffing box 11. During operation, the stem of the first bolt 121 passes through the first through hole of the gland 13 from left to right and is threadedly connected to the first internal threaded hole of the stuffing box 11. Therefore, when tightening the first bolt 121, the head of the first bolt 121 drives the gland 13 to the right close to the stuffing box 11, and the protrusion 15 of the gland 13 presses the packing 17 to the right, causing the packing 17 to be displaced radially along the push rod 10, thereby achieving shaft sealing. Of course, in other embodiments, the first fastener 12 may also adopt a structure in which a stud and a nut cooperate, or may adopt other existing structures, as long as the connection between the gland 13 and the stuffing box 11 can be achieved and the gland 13 can be brought close to the stuffing box 11 when tightened, and no specific limitation is made here.

[0032] In some embodiments, see Figure 1The first fastener 12 further includes a first nut 122, which is disposed between the gland 13 and the stuffing box 11 and is threadedly connected to the stem of the first bolt 121. After the first bolt 121 is tightened in place, the first nut 122 is tightened to clamp the gland 13 with the head of the first bolt 121 and the first nut 122, so that the gland 13 can be prevented from shifting due to external force during the operation of the boiler.

[0033] In some embodiments, see Figure 1 , the first end of the expansion joint 18 overlaps the outer surface of the second end of the stuffing box 11 and is fixed by the first pipe clamp 23. Specifically, the left end of the expansion joint 18 has a cylindrical first overlap section, the first overlap section is sleeved on the outer surface of the right end of the stuffing box 11, and is fixed by the first pipe clamp 23. In order to improve the sealing performance of the connection between the expansion joint 18 and the stuffing box 11, an O-ring may be provided between the outer surface of the stuffing box 11 and the inner surface of the first overlap section. In other embodiments, the first end of the expansion joint 18 may also be sealed and connected to the stuffing box 11 by welding.

[0034] In some embodiments, see Figure 1 , an extension portion 24 extending toward the expansion joint 18 is provided on the mounting plate 19, and the second end of the expansion joint 18 is overlapped on the extension portion 24 and fixed by a second pipe clamp 25. Specifically, the extension portion 24 is cylindrical, and the right end of the extension portion 24 is fixedly connected to the mounting plate 19 by welding. The right end of the expansion joint 18 has a cylindrical second overlap section, which is sleeved on the outer surface of the extension portion 24 and fixed by a second pipe clamp 25. In order to improve the sealing performance of the connection between the expansion joint 18 and the extension portion 24, an O-ring may be further provided between the outer surface of the extension portion 24 and the inner surface of the second overlap section. In other embodiments, the second end of the expansion joint 18 may also be sealed and connected to the extension portion 24 or the mounting plate 19 by welding.

[0035] In some embodiments, see Figure 1 , a first gasket 26 is provided between the packing filler 17 and the protrusion 15, and a second gasket 27 is provided between the packing filler 17 and the limiting portion 16. Exemplarily, the first gasket 26 is annular and is sleeved on the mandrel 10. The inner diameter of the first gasket 26 is slightly larger than the outer diameter of the mandrel 10, and the outer diameter of the first gasket 26 is slightly smaller than the inner diameter of the stuffing box 11; the inner diameter of the second gasket 27 is slightly larger than the outer diameter of the mandrel 10, and the outer diameter of the second gasket 27 is slightly smaller than the inner diameter of the stuffing box 11. Therefore, when the packing filler 17 is compressed by the protrusion 15, the packing filler 17 can be prevented from entering the gap between the inner surface of the protrusion 15 and the outer surface of the mandrel 10, and between the inner surface of the limiting portion 16 and the outer surface of the mandrel 10.

[0036] In some embodiments, see Figure 1 , a third gasket 28 is provided between the heat insulating material 22 and the mounting plate 19. Exemplarily, the third gasket 28 is annular and is sleeved on the mandrel 10. The inner diameter of the third gasket 28 is slightly larger than the outer diameter of the mandrel 10, and the outer diameter of the third gasket 28 is larger than the inner diameter of the mounting plate 19. Thus, when the heat insulating material 22 is filled in the heat insulating space 21, the heat insulating material can be prevented from entering the interior of the furnace shell 20 through the gap between the mounting plate 19 and the mandrel 10.

[0037] When in use, the mandrel 10 drives the grate in the furnace to operate through its own axial movement and radial swing. When the mandrel 10 moves, the stuffing box 11 needs to move with the mandrel 10. In order to improve the reliability of the installation of the stuffing box 11 and reduce the additional load generated by the stuffing box 11 on the expansion joint 18, in some embodiments, see Figure 1 The first end of the stuffing box 11 is connected to the mounting plate 19 via a movable assembly 29, so that the stuffing box 11 can swing radially. By providing the movable assembly 29, which is used to connect the first end of the stuffing box 11 to the mounting plate 19, when the push rod 10 is in a stationary state, the stuffing box 11 is supported by the movable assembly 29, which reduces the additional load of the stuffing box 11 on the expansion joint 18 and improves the reliability of the overall sealing structure; when the push rod 10 swings radially, it can also drive the stuffing box 11 to swing radially.

[0038] In some embodiments, see Figure 1 The movable assembly 29 includes two connecting rods 291 arranged in parallel on the upper and lower sides of the stuffing box 11, and the two ends of the connecting rod 291 are respectively hinged to the first end of the stuffing box 11 and the mounting plate 19, so that the push rod 10 can drive the stuffing box 11 to swing up and down. Exemplarily, a first ear plate 292 is fixed to the outer surface of the left end of the stuffing box 11, and a second ear plate 293 is fixed to the mounting plate 19. The two ends of the connecting rod 291 are respectively hinged to the first ear plate 292 and the second ear plate 293 through a horizontally arranged pin shaft, wherein the pin shaft is perpendicular to the connecting rod 291.

[0039] The above is only a preferred embodiment of the present application and does not constitute any form of limitation to the present application. Based on the technical essence of the present application and within the spirit and principles of the present application, any simple modification, equivalent replacement and improvement of the above embodiments shall still fall within the protection scope of the technical solution of the present application.

Claims

1. A grate top rod sealing structure, characterized in that: It comprises a stuffing box (11) sleeved on a push rod (10), wherein a first end of the stuffing box (11) is connected to a gland (13) via a first fastener (12); The gland (13) is provided with a protrusion (15) extending into a sealed space (14) between an inner wall of the stuffing box (11) and the push rod (10); a limiting portion (16) is provided on the inner wall of the second end of the stuffing box (11); and a packing (17) clamped by the protrusion (15) and the limiting portion (16) is provided in the sealed space (14); The second end of the stuffing box (11) is sealedly connected to a mounting plate (19) via an expansion joint (18); the mounting plate (19) is used to be fixed to the outside of a furnace shell (20); and a heat-insulating material (22) is provided in a heat-insulating space (21) enclosed by the stuffing box (11), the expansion joint (18), the mounting plate (19) and the top rod (10).

2. The grate top rod sealing structure according to claim 1, characterized in that: The first fastener (12) comprises a first bolt (121), the stem of the first bolt (121) passing through the gland (13) and then being threadedly connected to the stuffing box (11).

3. The grate top rod sealing structure according to claim 2, characterized in that: The first fastener (12) further comprises a first nut (122), wherein the first nut (122) is arranged between the gland (13) and the stuffing box (11) and is threadedly connected to the stem of the first bolt (121).

4. The grate top rod sealing structure according to claim 1, characterized in that: The stuffing box (11) and the limiting portion (16) are an integrally formed structure.

5. The grate top rod sealing structure according to claim 1, characterized in that: The first end of the expansion joint (18) is overlapped on the outer surface of the second end of the stuffing box (11) and is fixed by a first pipe clamp (23).

6. The grate top rod sealing structure according to claim 5, characterized in that: The mounting plate (19) is provided with an extension portion (24) extending toward the expansion joint (18); the second end of the expansion joint (18) is overlapped on the extension portion (24) and fixed by a second pipe clamp (25).

7. The grate top rod sealing structure according to claim 1, characterized in that: A first gasket (26) is provided between the packing filler (17) and the protruding portion (15), and a second gasket (27) is provided between the packing filler (17) and the limiting portion (16).

8. The grate top rod sealing structure according to claim 1, characterized in that: A third gasket (28) is provided between the thermal insulation material (22) and the mounting plate (19).

9. The grate top rod sealing structure according to claim 1, characterized in that: The first end of the stuffing box (11) is connected to the mounting plate (19) via a movable component (29) so that the stuffing box (11) can swing in the radial direction.

10. The grate top rod sealing structure according to claim 9, characterized in that: The movable component (29) comprises two connecting rods (291) arranged in parallel on the upper and lower sides of the stuffing box (11), and the two ends of the connecting rod (291) are respectively hinged to the first end of the stuffing box (11) and the mounting plate (19).

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