Suspended sealing device of air pre-heater

Abstract

The utility model discloses an air pre-heater suspension type sealing device. A floating structure is arranged on the left side of a sector plate, and a hard sealing strip is arranged on the right side of the sector plate. The floating structure comprises a left clamping plate, a right clamping plate, a connecting plate, a floating sealing strip and an elastic assembly, one ends of the left clamping plate, the right clamping plate, the connecting plate and the floating sealing strip are fixed to the center cylinder, the connecting plate and the floating sealing strip are located between the left clamping plate and the right clamping plate, and gaps are reserved between the floating sealing strip and the left clamping plate and between the floating sealing strip and the right clamping plate. The floating sealing structure is mounted in the constant-state area of the rotor, so that the floating sealing structure is approximate to a constant state in both cold and hot states and is not in contact with the fan-shaped plate without friction, the abrasion defect of contact type sealing is avoided, the compensation effect equivalent to the contact type sealing can be achieved, and the air leakage rate in the initial state can be basically kept unchanged within several years.

Description

Technical Field

[0001] The present application relates to the technical field of air preheater sealing, and in particular to a suspended sealing device for an air preheater. Background Art

[0002] Air preheater is a widely used equipment in large thermal power plants. Its main function is to improve the thermal efficiency of the boiler. During operation, the air preheater rotor will expand or contract due to temperature changes, which is called thermal deformation. This thermal deformation may cause the gap between the rotor and the fixed parts to change, affecting the sealing performance of the equipment.

[0003] In the existing sealing technology, brush seals are usually composed of brushes, which are embedded in the gap between the rotor and the housing to prevent the leakage of smoke and air. However, brush seals have poor adaptability to thermal deformation of the rotor because the brushes have limited elasticity and cannot effectively compensate for the gap changes caused by thermal deformation.

[0004] Sliding flexible seals rely on the elasticity or sliding characteristics of the seal to adapt to a certain displacement, but they also have limitations. Under extreme working conditions of the air preheater, the sliding parts may lose their effective sealing effect due to excessive thermal deformation, resulting in flue gas leakage, affecting environmental protection indicators and equipment efficiency. Utility Model Content

[0005] To this end, the present application provides an air preheater suspension sealing device to solve the problem in the prior art that the sealing structure cannot effectively compensate for the gap change caused by thermal deformation of the rotor.

[0006] In order to achieve the above objectives, this application provides the following technical solutions:

[0007] An air preheater suspension sealing device comprises a central tube and a sector plate fixed on the side wall of the central tube, a floating structure is arranged on the left side of the sector plate, and a hard sealing strip is arranged on the right side, and the hard sealing strip is fixed to the upper and lower ends of the sector plate by bolts;

[0008] The floating structure comprises a left clamping plate, a right clamping plate, a connecting plate, a floating sealing strip and an elastic component. One end of the left clamping plate, the right clamping plate, the connecting plate and the floating sealing strip are all fixed on the central tube. The connecting plate and the floating sealing strip are both located between the left clamping plate and the right clamping plate, and the connecting plate is located below the floating sealing strip. The left and right sides of the connecting plate are respectively fixedly connected to the left clamping plate and the right clamping plate. A gap is left between the floating sealing strip and the left clamping plate and the right clamping plate. The left clamping plate, the connecting plate, the right clamping plate, the fan-shaped plate and the hard sealing strip are connected by bolts.

[0009] The elastic component is arranged on the left side of the floating sealing strip, and includes a spring, a shaft, an upper plate, a lower plate and a bracket. The upper plate and the lower plate are installed on the shaft. The spring is wound on the shaft, and the upper end is connected to the upper plate, and the lower end is connected to the lower plate; the bracket is fixedly connected to the floating sealing strip and connected to the upper end of the shaft.

[0010] Optionally, a fixing plate is provided at the bottom of the floating sealing strip, the fixing plate is installed at one end of the floating sealing strip close to the center tube, and one end of the fixing plate is fixed to the center tube; the connecting plate is located on the side of the fixing plate away from the center tube and below the floating sealing strip.

[0011] Optionally, it also includes a plurality of labyrinth sealing strips arranged at the lower end of the sector plate, and the plurality of labyrinth sealing strips are installed on the left side of the sector plate.

[0012] Further optionally, two sub-plates are provided at the lower end of the multi-lane labyrinth sealing strip, and the distance between the two sub-plates gradually increases from top to bottom.

[0013] Optionally, a spoiler is provided on one side below the sector plate, and the distance between the spoiler and the sector plate gradually increases from bottom to top.

[0014] Optionally, the shaft is a screw rod, the upper plate is fixed on the shaft, the lower plate can move up and down along the shaft, and the shaft is also threaded with a nut, which is located below the lower plate.

[0015] Further optionally, the nut is connected to the lower plate and the shaft rod by welding.

[0016] Optionally, a plurality of connecting plates are provided along the width direction of the fan-shaped plate, chamfers are provided at the tops of both ends of the connecting plates, and a gap is left between two adjacent connecting plates.

[0017] Optionally, the hard sealing strip is made of Corten steel.

[0018] Optionally, the multi-lane labyrinth sealing strips are made of high-strength corrosion-resistant and wear-resistant alloy steel.

[0019] Compared with the prior art, this application has at least the following beneficial effects:

[0020] 1. The hard seal can ensure the strength of the whole device and has a low failure rate. With the help of the floating structure, when the rotor expands thermally, the floating seal strip is a cantilever design with one end connected to the center tube and the other end free. Therefore, the end tends to move upward under the elastic force of the elastic component, so that it can basically maintain a horizontal state in the working state, automatically compensate for the rotor drop, and keep the sealing gap between the sealing sheet and the fan plate at a relatively small value.

[0021] 2. By setting up multiple labyrinth sealing strips, a damping effect can be formed between the hard sealing strips, increasing the direct air leakage resistance and thus reducing leakage.

[0022] 3. Adding spoilers on the side of the fan-shaped plate can reduce the amount of air on the inner side of the fan-shaped plate (the edge of the fan-shaped plate), thereby reducing leakage.

[0023] 4. The shaft is set as a screw rod, which makes it easy to adjust the compression of the spring according to the properties of the rotor by adjusting the position of the nut.

[0024] 5. Leave gaps between adjacent connecting plates to facilitate dust falling from the middle and prevent dust accumulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more intuitively illustrate the prior art and the present application, exemplary drawings are given below. It should be understood that the specific shapes and structures shown in the drawings should not generally be regarded as limiting conditions for implementing the present application; for example, those skilled in the art are capable of easily making conventional adjustments or further optimizations to the addition / reduction / attribution division, specific shapes, positional relationships, connection methods, dimensional ratios, etc. of certain units (components) based on the technical concepts and exemplary drawings disclosed in the present application.

[0026] Figure 1 A schematic diagram of the overall structure of an air preheater suspension sealing device provided in an embodiment of the present application;

[0027] Figure 2 for Figure 1 The enlarged schematic diagram of point A in the middle;

[0028] Figure 3 This is a partial side view of an embodiment of the present application, which is intended to illustrate the positional relationship of various components;

[0029] Figure 4 A side view of an embodiment of the present application;

[0030] Figure 5 for Figure 4 Structural diagram of the middle connecting plate;

[0031] Figure 6 for Figure 1 The enlarged schematic diagram of point B in the middle;

[0032] Figure 7 It is the deformation curve diagram of the fan plate and the rotor.

[0033] Description of reference numerals:

[0034] 1. Fan-shaped plate; 2. Hard sealing strip; 3. Left clamping plate; 4. Right clamping plate; 5. Connecting plate; 6. Floating sealing strip; 7. Fixed plate; 8. Spring; 9. Shaft rod; 10. Upper plate; 11. Lower plate; 12. Bracket; 13. Nut; 14. Multi-pass labyrinth sealing strip; 15. Spoiler. DETAILED DESCRIPTION

[0035] The present application is further described below in detail through specific embodiments in conjunction with the accompanying drawings.

[0036] In the description of this application: unless otherwise specified, the meaning of "plurality" is two or more. The terms "first", "second", "third", etc. in this application are intended to distinguish the objects referred to, and do not have special meanings in terms of technical connotations (for example, they should not be understood as emphasizing the importance or order, etc.). Expressions such as "including", "comprising", "having", etc. also mean "not limited to" (certain units, components, materials, steps, etc.).

[0037] The terms such as "upper", "lower", "left", "right", "middle", etc. cited in this application are usually used to indicate the general relative position relationship for the purpose of intuitive understanding by referring to the drawings, and are not absolute limitations on the position relationship in the actual product.

[0038] An air preheater suspension sealing device, referring to Figure 1 and Figure 2 , including a central tube and a plurality of sector plates 1 fixed to the side wall of the central tube. A floating structure is provided on the left side of each sector plate 1, and a hard sealing strip 2 is provided on the right side. The hard sealing strip 2 is made of thick Corten steel to reduce the failure rate, and is fixed to the upper and lower ends of the sector plate 1 by bolts.

[0039] Reference Figure 2 and Figure 3 The floating structure includes a left clamping plate 3 (i.e., a rotor), a right clamping plate 4 (i.e., a rotor), a connecting plate 5, a floating sealing strip 6, and an elastic component. The left clamping plate 3 and the right clamping plate 4 are both in the shape of right angle plates, and the directions of the two are opposite to each other.

[0040] Among them, one end of the left clamping plate 3, the right clamping plate 4, the connecting plate 5 and the floating sealing strip 6 are fixed on the side wall of the central tube along the axial direction. The connecting plate 5 and the floating sealing strip 6 are both between the left clamping plate 3 and the right clamping plate 4, and the connecting plate 5 is below the floating sealing strip 6. The left and right sides of the connecting plate 5 are respectively fixedly connected to the left clamping plate 3 and the right clamping plate 4, so that the gap between the left clamping plate 3 and the right clamping plate 4 remains stable. The thickness of the floating sealing strip 6 is less than that of the connecting plate 5, so there is a gap between the floating sealing strip 6 and the left clamping plate 3 and the right clamping plate 4, so that it can move freely up and down.

[0041] Reference Figure 4and Figure 5 Specifically, the lower part of the floating sealing strip 6 is between the left clamping plate 3 and the right clamping plate 4, and the upper part is higher than the left clamping plate 3 and the right clamping plate 4. A fixing plate 7 is provided at the bottom of the floating sealing strip 6, and the fixing plate 7 is installed at one end of the floating sealing strip 6 close to the center tube by bolts, and one end of the fixing plate 7 is fixed to the center tube. The connecting plate 5 is located at the side of the fixing plate 7 away from the center tube and below the floating sealing strip 6. A gap is left between the top of the connecting plate 5 and the bottom of the floating sealing strip 6.

[0042] Reference Figure 7 The air preheater rotor produces a "mushroom-shaped deformation" in the hot state, that is, the end gradually expands downward. The intersection of the expansion curve after deformation and the cold state is called the expansion zero position, which can be considered as the constant state area. The fixed plate 7 is in the constant state area, and the end of the floating sealing strip 6 is fixed.

[0043] In order to prevent dust from accumulating on the top of the connecting plate 5, a plurality of connecting plates 5 are provided at intervals along the width direction of the sector plate 1. The tops of both ends of each connecting plate 5 are provided with inclined surfaces or curved chamfers, and a gap is also left between two adjacent connecting plates 5 so that dust can fall therefrom. In this embodiment, seven connecting plates 5 are installed on each sector plate 1, and each connecting plate 5 is penetrated with two bolts to connect the connecting plate 5 with the left clamping plate 3, the right clamping plate 4, the sector plate 1 and the hard sealing strip 2.

[0044] Specifically, the left clamping plate 3, the connecting plate 5, the right clamping plate 4, the sector plate 1 and the hard sealing strip 2 are all connected by the same bolt. To ensure the overall stability, a plurality of such bolts are arranged along the width direction.

[0045] Reference Figure 2 and Figure 3 The elastic component is arranged on the left side of the floating sealing strip 6, and includes a spring 8, a shaft 9, an upper plate 10, a lower plate 11 and a bracket 12. The upper plate 10 and the lower plate 11 are both mounted on the shaft 9, the spring 8 is wound around the shaft 9, the upper end of the spring 8 is connected to the upper plate 10, and the lower end is connected to the lower plate 11. In a specific implementation, the two ends of the spring 8 can be fixed by welding. One end of the bracket 12 is fixedly connected to the portion of the floating sealing strip 6 that is higher than the left clamping plate 3, and the other end is connected to the upper end of the shaft 9.

[0046] In order to facilitate the adjustment of the initial compression amount of the spring 8 during installation, the shaft 9 is set as a screw, and the thread is opened at the lower part of the shaft 9. Specifically, the upper plate 10 is fixed at the position where the shaft 9 has no thread, and a through hole is opened in the middle of the lower plate 11 so that it can move freely up and down along the shaft 9. The threaded part of the shaft 9 is matched with a nut 13, and the nut 13 is located below the lower plate 11. By turning the nut 13, the position of the nut 13 on the shaft 9 is adjusted, and the nut 13 can support the lower plate 11 to prevent it from being ejected downward by the spring 8.

[0047] In order to enhance the strength and stability of the elastic component, a safety design is provided thereon. The specific operation is as follows: after adjusting the position of the lower plate 11, the nut 13 is welded to the lower plate 11 and the shaft 9 to prevent the nut 13 from loosening; and the connection between the bracket 12 and the floating sealing strip 6 is also connected by welding.

[0048] Therefore, when the rotor expands thermally, the spring 8 always has a preload force, so it will push the floating seal strip 6 upward, so that it always has a tendency to move upward. Since the floating seal strip 6 is not in contact with the left clamping plate 3 and the right clamping plate 4, when the left clamping plate 3 and the right clamping plate 4 expand downward, the floating seal strip 6 can still remain in a nearly horizontal state to make up for the gap caused by the deformation and reduce air leakage.

[0049] Reference Figure 6 Furthermore, a multi-channel labyrinth sealing strip 14 is provided on the left side of the lower end of each sector plate 1, and two sub-plates are provided at the lower end of the multi-channel labyrinth sealing strip 14, and the distance between the two sub-plates gradually increases from top to bottom, thereby forming a damping effect between the multi-channel labyrinth seal and the hard sealing strip 2, increasing the direct air leakage resistance, thereby reducing leakage.

[0050] In this embodiment, the multi-channel labyrinth sealing strips 14 are made of high-strength corrosion-resistant and wear-resistant alloy steel.

[0051] Reference Figure 1 Furthermore, a spoiler 15 is provided on the left side below the leftmost fan-shaped plate 1. The spoiler 15 is an arc-shaped plate, and the spacing between the spoiler 15 and the fan-shaped plate 1 gradually increases from bottom to top. With such a structure, the amount of air on the inner side of the fan-shaped plate 1 can be reduced, thereby further reducing leakage.

[0052] The implementation principle of the embodiment of the present application is as follows: by setting up a suspended sealing device, since the floating sealing strip 6 does not contact the fan plate 1 and the left clamping plate 3 and the right clamping plate 4, when the fan plate 1, the left clamping plate 3 and the right clamping plate 4 are deformed downward due to thermal expansion, the end of the floating sealing strip 6 can basically maintain a horizontal state in the working state with the assistance of the elastic component, and can automatically compensate for the amount of rotor descent, so that the sealing gap between the sealing sheet and the fan plate 1 is maintained at a relatively small value.

[0053] At the same time, the multi-channel labyrinth seal strip 14 increases the direct air leakage resistance, thereby reducing leakage. And under the effect of the spoiler 15, the air volume at the edge of the fan-shaped plate 1 is reduced, further reducing leakage.

[0054] The technical features of the above embodiments may be arbitrarily combined (as long as there is no contradiction in the combination of these technical features). To make the description concise, not all possible combinations of the technical features in the above embodiments are described; these embodiments that are not explicitly written should also be considered to be within the scope of this specification.

Claims

1. An air preheater suspension sealing device, comprising a central tube and a sector plate (1) fixed to the side wall of the central tube, characterized in that: A floating structure is provided on the left side of the sector plate (1), and a hard sealing strip (2) is provided on the right side, wherein the hard sealing strip (2) is fixed to the upper and lower ends of the sector plate (1) by bolts; The floating structure comprises a left clamping plate (3), a right clamping plate (4), a connecting plate (5), a floating sealing strip (6) and an elastic component. One end of the left clamping plate (3), the right clamping plate (4), the connecting plate (5) and the floating sealing strip (6) are all fixed on the central tube. The connecting plate (5) and the floating sealing strip (6) are both located between the left clamping plate (3) and the right clamping plate (4), and the connecting plate (5) is located below the floating sealing strip (6). The left and right sides of the connecting plate (5) are respectively fixedly connected to the left clamping plate (3) and the right clamping plate (4). A gap is left between the floating sealing strip (6) and the left clamping plate (3) and the right clamping plate (4); the left clamping plate (3), the connecting plate (5), the right clamping plate (4), the fan-shaped plate (1) and the hard sealing strip (2) are connected by bolts. The elastic component is arranged on the left side of the floating sealing strip (6), and comprises a spring (8), a shaft (9), an upper plate (10), a lower plate (11) and a bracket (12); the upper plate (10) and the lower plate (11) are mounted on the shaft (9); the spring (8) is wound around the shaft (9), the upper end of the spring (8) is connected to the upper plate (10), and the lower end of the spring (8) is connected to the lower plate (11); the bracket (12) is fixedly connected to the floating sealing strip (6), and is connected to the upper end of the shaft (9).

2. The air preheater suspension sealing device according to claim 1 is characterized in that: A fixing plate (7) is provided at the bottom of the floating sealing strip (6), the fixing plate (7) is installed at one end of the floating sealing strip (6) close to the central tube, and one end of the fixing plate (7) is fixed on the central tube; the connecting plate (5) is located on the side of the fixing plate (7) away from the central tube and below the floating sealing strip (6).

3. The air preheater suspension sealing device according to claim 1 is characterized in that: It also comprises a plurality of labyrinth sealing strips (14) arranged at the lower end of the sector plate (1), wherein the plurality of labyrinth sealing strips (14) are installed on the left side of the sector plate (1).

4. The air preheater suspension sealing device according to claim 3 is characterized in that: Two sub-plates are arranged at the lower end of the multi-channel labyrinth sealing strip (14), and the distance between the two sub-plates gradually increases from top to bottom.

5. The air preheater suspension sealing device according to claim 1 is characterized in that: A spoiler (15) is provided on one side below the sector plate (1), and the distance between the spoiler (15) and the sector plate (1) gradually increases from bottom to top.

6. The air preheater suspension sealing device according to claim 1, characterized in that: The shaft (9) is a screw rod, the upper plate (10) is fixed on the shaft (9), the lower plate (11) can move up and down along the shaft (9), and the shaft (9) is also threadedly equipped with a nut (13), and the nut (13) is located below the lower plate (11).

7. The air preheater suspension sealing device according to claim 6, characterized in that: The nut (13) is connected to the lower plate (11) and the shaft rod (9) by welding.

8. The air preheater suspension sealing device according to claim 1 or 2, characterized in that: A plurality of connecting plates (5) are provided along the width direction of the sector plate (1), the tops of both ends of the connecting plates (5) are provided with chamfers, and a gap is left between two adjacent connecting plates (5).

9. The air preheater suspension sealing device according to claim 1, characterized in that: The hard sealing strip (2) is made of Corten steel.

10. The air preheater suspension sealing device according to claim 3 or 4, characterized in that: The multi-channel labyrinth sealing strip (14) is made of high-strength corrosion-resistant and wear-resistant alloy steel.

Images