Low resistance noise reduction air preheater seal structure

Abstract

The utility model discloses a low resistance noise reduction air preheater sealing structure, including boiler body still includes fixedly connected in the flue gas exhaust pipe of boiler body one side, installs the air preheater body in the boiler body one side, fixedly connected in the flue gas inlet pipe of air preheater body one side, fixedly connected on the connecting flange of flue gas exhaust pipe and flue gas inlet pipe, the annular sealing groove of opening in the connecting flange one side, the utility model discloses the sealing member can improve the sealing effect, reduced energy waste, improved system thermal efficiency, reduced operating cost, and fixed assembly greatly optimized the replacement process of sealing ring. The operator need not complicated tool and tedious step, can complete the replacement work of sealing ring fast, make sealing ring replacement operation become simple and fast, this not only promotes the efficiency of equipment maintenance, shortens the equipment downtime, but also enhances the reliability of equipment maintenance, ensures that equipment can long -term stable operation.

Description

Technical Field

[0001] This utility model relates to the field of air preheater technology, and in particular to a low-resistance, noise-reducing air preheater sealing structure. Background Technology

[0002] A heat pipe air preheater is a heat exchange device that uses the principle of heat pipes to preheat air. It utilizes heat pipe technology to recover heat energy from waste gas (or flue gas) and preheat cooling air, thereby improving the thermal efficiency and energy utilization efficiency of industrial equipment. Its key technologies include heat pipe technology, air preheating technology, material selection and manufacturing processes, and system integration and control.

[0003] In practical applications, existing low-resistivity, noise-reducing air preheaters require proper connection between the industrial boiler and the preheater. During boiler operation, flue gas enters the preheater through a pre-set flue gas inlet; simultaneously, outside cold air enters through the air inlet. Inside the preheater, efficient heat exchange occurs between the flue gas and cold air. The heat carried by the flue gas is transferred to the cold air, heating it. The heated air can then be used for boiler combustion or other process requirements, effectively improving energy efficiency.

[0004] However, some current heat pipe air preheaters use bolted flanges for connection to the boiler. In this method, the contact surface between the sealing ring and the flange is flat, resulting in a relatively simple overall structure. However, this simple structure has certain drawbacks in actual operation, potentially leading to flue gas leakage. Once hot air leaks out, it not only wastes energy directly but also reduces the thermal efficiency of the entire system, affecting the normal operation of the boiler and related processes, and increasing operating costs. Furthermore, the sealing ring will gradually age and deteriorate due to heat and oxidation after prolonged use. Replacing the aged sealing ring is inconvenient, time-consuming, and labor-intensive. During the replacement process, special tools are required to unscrew the bolts of the fixing flange one by one. The entire disassembly process is slow, which seriously affects the maintenance efficiency and uptime of the equipment. When the flue gas enters the air preheater from the boiler, the amount of flue gas generated may decrease sharply and the pressure in the furnace may drop. If the air preheater inlet remains at a relatively high pressure due to the high resistance, the flue gas may flow back due to the reverse driving force of "flow from the low pressure area to the high pressure area". Flue gas backflow will not only interfere with the normal heat exchange process of the air preheater, but may also have an adverse effect on the combustion conditions of the boiler. Utility Model Content

[0005] To overcome the shortcomings of existing technologies, the purpose of this utility model is to provide a low-resistance, noise-reducing air preheater sealing structure, which can improve the sealing effect, reduce energy waste, improve system thermal efficiency, reduce operating costs, make the replacement of sealing rings simple and quick, improve the efficiency and reliability of equipment maintenance, effectively prevent flue gas backflow, avoid interference with air preheater heat exchange and boiler combustion, ensure stable system operation, and reduce the risk of equipment damage and safety accidents.

[0006] The objective of this utility model is achieved through the following technical solution:

[0007] The low-resistance, noise-reducing air preheater sealing structure includes a boiler body; it also includes a flue gas exhaust pipe fixedly connected to one side of the boiler body, an air preheater body installed on one side of the boiler body, a flue gas inlet pipe fixedly connected to one side of the air preheater body, a connecting flange fixedly connected to the flue gas exhaust pipe and the flue gas inlet pipe, an annular sealing groove opened on one side of the connecting flange, a sealing element installed between two sets of connecting flanges for sealing, a fixing assembly installed on the outside of the connecting flange for fixing the two sets of connecting flanges, and an anti-backflow assembly installed on the inside of the air preheater body.

[0008] In one optional embodiment, the sealing element includes a sealing gasket installed between two sets of connecting flanges, two annular sealing protrusions disposed on the sealing gasket, and a sealing skirt disposed around the outer perimeter of the sealing gasket. The annular sealing protrusions are concentrically distributed and are interference-fitted with the annular sealing groove.

[0009] In one optional embodiment, two sets of two concentric annular sealing protrusions are provided and are symmetrically distributed on both sides of the sealing gasket.

[0010] In one optional embodiment, the fixing assembly includes a first fixing ring mounted on two sets of connecting flanges, a second fixing ring rotatably connected at one end to the first fixing ring, a rotating block rotatably connected to the other end of the second fixing ring, a threaded rod fixedly connected to the rotating block, and a hexagonal nut threadedly connected to the threaded rod. When the second fixing ring rotates until the threaded rod engages with the first fixing ring, the other end of the second fixing ring is fixed to the first fixing ring via the threaded rod and the hexagonal nut.

[0011] In one optional embodiment, both the first fixing ring and the second fixing ring have trapezoidal grooves on their inner sides. When the fixing assembly is installed on the connecting flange, the grooves are interference-fitted with the outer surface of the connecting flange.

[0012] In one optional embodiment, the anti-backflow assembly includes a fixed frame fixedly connected to the inside of the air preheater body, a return spring fixedly connected to the fixed frame, a sealing block fixedly connected to the return spring, a sealing ring installed on the sealing block, and a guide rod fixedly connected to one side of the sealing block. The sealing block is slidably connected to the inside of the fixed frame.

[0013] In one optional embodiment, the sealing block has a frustum-shaped structure, with the top surface of the frustum facing the flue gas inlet pipe.

[0014] In one optional embodiment, two sets of sealing rings are provided, and the two sets of sealing rings are concentrically distributed on the inclined surface of the sealing block.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0016] 1. The sealing element of this utility model can improve the sealing effect, reduce energy waste, improve system thermal efficiency, and reduce operating costs; and the fixing component greatly optimizes the sealing ring replacement process. Operators can quickly complete the sealing ring replacement without complicated tools and cumbersome steps, making the sealing ring replacement operation simple and fast. This not only improves the efficiency of equipment maintenance and shortens equipment downtime, but also enhances the reliability of equipment maintenance and ensures that the equipment can operate stably for a long time.

[0017] 2. The anti-backflow component of this utility model can effectively prevent flue gas backflow, avoid interference with heat exchange in the air preheater and boiler combustion, ensure stable operation of the system, and reduce the risk of equipment damage and safety accidents. Attached Figure Description

[0018] Figure 1 A three-dimensional structural diagram of the sealing structure of a low-resistance, noise-reducing air preheater;

[0019] Figure 2 A cross-sectional schematic diagram of the sealing structure of a low-resistance, noise-reducing air preheater.

[0020] Figure 3 A cross-sectional view of the boiler body, sealing gasket, first fixed ring, second fixed ring, rotating block, threaded rod and nut assembly for the sealing structure of a low-resistance noise reduction air preheater;

[0021] Figure 4 A cross-sectional view of the flue gas exhaust pipe, flue gas inlet pipe, connecting flange, sealing gasket, first fixing ring and second fixing ring of the sealing structure of a low-resistance noise reduction air preheater.

[0022] Figure 5A cross-sectional view of the flue gas exhaust pipe, flue gas inlet pipe, connecting flange, annular sealing groove, first fixed ring, second fixed ring, rotating block, threaded rod and nut combination structure of the sealing structure of the low resistance noise reduction air preheater.

[0023] Figure 6 A three-dimensional structural diagram of the sealing component for a low-resistance, noise-reducing air preheater.

[0024] Figure 7 A cross-sectional view of the air preheater body, flue gas inlet pipe, connecting flange, fixing frame, return spring, sealing block, sealing ring, and guide rod assembly for a low-resistance, noise-reducing air preheater sealing structure.

[0025] Explanation of reference numerals in the attached drawings: 1. Boiler body; 2. Flue gas exhaust pipe; 3. Air preheater body; 4. Flue gas inlet pipe; 501. Connecting flange; 502. Annular sealing groove; 503. Sealing gasket; 504. Annular sealing protrusion; 505. Sealing skirt; 601. First fixing ring; 602. Second fixing ring; 603. Rotating block; 604. Threaded rod; 605. Hexagonal nut; 701. Fixing bracket; 702. Return spring; 703. Sealing block; 704. Sealing ring; 705. Guide rod. Detailed Implementation

[0026] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments. Unless otherwise specified, the materials and equipment used in this embodiment are all commercially available. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0027] In the description of this application, it should be understood that the terms "upper," "lower," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In the description of this application, "a plurality of" means two or more, unless otherwise precisely specified.

[0028] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "connected," "linked," and "connected" should be interpreted broadly. For example, they can refer to a fixed connection, a connection through an intermediary, the internal connection of two elements, or the interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0029] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or apparatus.

[0030] Please refer to Figures 1-7 The low-resistance, noise-reducing air preheater sealing structure includes a boiler body 1; it also includes a flue gas exhaust pipe 2 fixedly connected to one side of the boiler body 1, an air preheater body 3 installed on one side of the boiler body 1, a flue gas inlet pipe 4 fixedly connected to one side of the air preheater body 3, a connecting flange 501 fixedly connected to the flue gas exhaust pipe 2 and the flue gas inlet pipe 4, an annular sealing groove 502 opened on one side of the connecting flange 501, a sealing element installed between the two sets of connecting flanges 501 for sealing, a fixing assembly installed on the outside of the connecting flange 501 for fixing the two sets of connecting flanges 501, and an anti-backflow assembly installed on the inside of the air preheater body 3.

[0031] In a preferred embodiment of this utility model, two sets of connecting flanges 501 are fixed by a fixing assembly to form a mechanical connection. A sealing element is installed between the two sets of connecting flanges 501. The connecting flanges 501 are compressed by the fixing assembly to generate elastic deformation of the sealing element, filling the tiny gap between the contact surfaces of the two sets of connecting flanges 501 to form a static seal. The sealing element maintains the sealing effect through its axial compensation capability to prevent flue gas leakage.

[0032] In a preferred embodiment of this utility model, the sealing element includes a sealing gasket 503 installed between two sets of connecting flanges 501, two annular sealing protrusions 504 disposed on the sealing gasket 503, and a sealing skirt 505 disposed around the outer circumference of the sealing gasket 503. The annular sealing protrusions 504 are concentrically distributed and are interference-fitted with the annular sealing groove 502. The two concentric annular sealing protrusions 504 and the annular sealing groove 502 form a multi-level sealing structure. The sealing reliability is improved through mechanical interlocking and pressure distribution optimization. The sealing skirt 505 prevents edge leakage through flexible deformation.

[0033] In a preferred embodiment of this utility model, two sets of concentric annular sealing protrusions 504 are provided and symmetrically distributed on both sides of the sealing gasket 503. Each set of annular sealing protrusions 504 includes two concentric rings, inner and outer, which cooperate with the corresponding grooves of the annular sealing groove 502 to form a symmetrical sealing structure and improve the sealing effect.

[0034] In a preferred embodiment of this utility model, the fixing assembly includes a first fixing ring 601 mounted on two sets of connecting flanges 501, a second fixing ring 602 rotatably connected at one end to the first fixing ring 601, a rotating block 603 rotatably connected to the other end of the second fixing ring 602, a threaded rod 604 fixedly connected to the rotating block 603, and a hexagonal nut 605 threadedly connected to the threaded rod 604. When the second fixing ring 602 rotates until the threaded rod 604 engages with the first fixing ring 601, the other end of the second fixing ring 602 is fixed to the first fixing ring 601 via the threaded rod 604 and the hexagonal nut 605. First, the first fixing ring 601 and the second fixing ring 602 are fitted onto the outside of the two sets of connecting flanges 501 that need to be fixed. Then, by rotating the rotating block 603, the threaded rod 604 is driven to rotate together until the threaded rod 604 enters the preset U-shaped groove on the connecting flange 501. At this point, rotate the hexagonal nut 605, gradually bringing it closer to the first retaining ring 601 until it is in close contact with the first retaining ring 601. During this process, the rotation of the hexagonal nut 605 will cause the first retaining ring 601 and the second retaining ring 602 to gradually contract, thereby exerting a squeezing effect on the two sets of connecting flanges 501, thus achieving a stable fixing effect.

[0035] Another embodiment based on fixed components:

[0036] Other structures in the existing technology can also be used, such as horn nuts, which can replace the hexagonal nuts 605. The advantage of horn nuts is that they can be operated directly by hand, and in emergency situations where professional tools are not available, they can be quickly disassembled or re-fixed to the connecting flange 501, reducing maintenance delays caused by the lack of tools.

[0037] In a preferred embodiment of this utility model, both the first fixing ring 601 and the second fixing ring 602 have trapezoidal grooves on their inner sides. When the fixing assembly is installed on the connecting flange 501, the grooves are interference-fitted with the outer surface of the connecting flange 501. This design not only enhances the fit between the first fixing ring 601 and the second fixing ring 602 and the connecting flange 501, but also improves the stability and reliability of the fixing.

[0038] In a preferred embodiment of this utility model, the anti-backflow component includes a fixed frame 701 fixedly connected to the inner side of the air preheater body 3, a return spring 702 fixedly connected to the fixed frame 701, a blocking block 703 fixedly connected to the return spring 702, a sealing ring 704 installed on the blocking block 703, and a guide rod 705 fixedly connected to one side of the blocking block 703. The blocking block 703 is slidably connected to the inner side of the fixed frame 701. When the flue gas flows normally in the designed direction, the flue gas applies a pressure in the same direction as the flow to the blocking block 703. At this point, the flue gas pressure overcomes the elastic force of the return spring 702, pushing the sealing block 703 and guide rod 705 to slide along the inner side of the fixing frame 701 in the pressure direction. As the sealing block 703 slides, the fluid channel originally blocked by the sealing block 703 gradually opens, allowing the fluid to pass smoothly through the channel and achieve normal heat exchange or transport functions. When an abnormal situation occurs causing the fluid to attempt to flow backward, the fluid in the backward direction applies a pressure to the sealing block 703 opposite to the normal flow direction. At this time, this backward pressure is in the same direction as the elastic force of the return spring 702. Under the combined action of the backward pressure and the elastic force of the return spring 702, the sealing block 703 slides along the inner side of the fixing frame 701 in the opposite direction, gradually approaching and finally tightly fitting against the sealing position inside the flue gas inlet pipe 4, blocking the fluid channel.

[0039] In a preferred embodiment of this utility model, the sealing block 703 has a frustum-shaped structure, with the top surface of the frustum facing the flue gas inlet pipe 4. The frustum-shaped structure allows the sealing block 703 to better fit against the abutment surface of the flue gas inlet pipe 4. During the sealing process, the sealing block 703 can gradually and evenly contact the abutment surface to form a tighter seal, effectively preventing fluid backflow and leakage.

[0040] In a preferred embodiment of this invention, two sets of sealing rings 704 are provided, concentrically distributed on the inclined surface of the sealing block 703. When fluid attempts to pass through, the first sealing ring 704 initially blocks most of the fluid, providing a preliminary seal. If a small amount of fluid breaches the first barrier, the second sealing ring 704 immediately takes effect, further preventing fluid leakage. This dual sealing mechanism significantly improves the overall sealing performance of the anti-backflow assembly, greatly reducing the risk of fluid backflow or leakage.

[0041] During operation, the first fixing ring 601 and the second fixing ring 602 are first fitted onto the outer sides of the two sets of connecting flanges 501 that need to be fixed. Then, by rotating the rotating block 603, the threaded rod 604 is rotated until it enters the pre-set U-shaped groove on the connecting flange 501. At this point, the hexagonal nut 605 is rotated, gradually moving closer to the first fixing ring 601 until it is in tight contact with it. During this process, the rotation of the hexagonal nut 605 causes the first fixing ring 601 and the second fixing ring 602 to gradually contract, thereby exerting a squeezing effect on the two sets of connecting flanges 501, achieving a stable fixing effect. The connecting flanges 501 compress the sealing element, causing elastic deformation and filling the tiny gap between the contact surfaces of the two sets of connecting flanges 501, forming a static seal. The sealing element maintains the sealing effect through axial compensation, preventing flue gas leakage. When the flue gas flows normally in the designed direction, the flue gas applies a flow-direction pressure to the sealing block 703. At this point, the flue gas pressure overcomes the elastic force of the return spring 702, pushing the sealing block 703 and guide rod 705 to slide along the inner side of the fixing frame 701 in the pressure direction. As the sealing block 703 slides, the fluid channel originally blocked by the sealing block 703 gradually opens, allowing the fluid to pass smoothly through the channel and achieve normal heat exchange or transport functions. When an abnormal situation occurs causing the fluid to attempt to flow backward, the fluid in the backward direction applies a pressure to the sealing block 703 opposite to the normal flow direction. At this time, this backward pressure is in the same direction as the elastic force of the return spring 702. Under the combined action of the backward pressure and the elastic force of the return spring 702, the sealing block 703 slides along the inner side of the fixing frame 701 in the opposite direction, gradually approaching and finally tightly fitting against the sealing position inside the flue gas inlet pipe 4, blocking the fluid channel.

[0042] Although only certain components and embodiments of this application have been illustrated and described, many modifications and alterations (e.g., variations in the size, dimensions, structure, shape and proportion of the various elements, installation arrangement, material use, color, orientation, etc.) will be conceived by those skilled in the art without actually departing from the scope and spirit of the claims.

[0043] Finally, it should be noted that the above embodiments are only preferred embodiments of this utility model and should not be used to limit the scope of protection of this utility model. Any non-substantial changes and substitutions made by those skilled in the art based on this utility model shall fall within the scope of protection claimed by this utility model.

Claims

1. A low-resistance, noise-reducing air preheater sealing structure, comprising a boiler body (1); characterized in that: It also includes a flue gas exhaust pipe (2) fixedly connected to one side of the boiler body (1), an air preheater body (3) installed on one side of the boiler body (1), a flue gas inlet pipe (4) fixedly connected to one side of the air preheater body (3), a connecting flange (501) fixedly connected to the flue gas exhaust pipe (2) and the flue gas inlet pipe (4), an annular sealing groove (502) opened on one side of the connecting flange (501), a sealing element installed between the two sets of connecting flanges (501) for sealing, a fixing assembly installed on the outside of the connecting flange (501) for fixing the two sets of connecting flanges (501), and an anti-backflow assembly installed on the inside of the air preheater body (3).

2. The low-resistance, noise-reducing air preheater sealing structure according to claim 1, characterized in that: The sealing element includes a gasket (503) installed between two sets of connecting flanges (501), two annular sealing protrusions (504) disposed on the gasket (503), and a sealing skirt (505) disposed around the outer circumference of the gasket (503). The annular sealing protrusions (504) are concentrically distributed and are interference-fitted with the annular sealing groove (502).

3. The low-resistance, noise-reducing air preheater sealing structure according to claim 2, characterized in that: Two sets of concentric annular sealing protrusions (504) are provided and are symmetrically distributed on both sides of the sealing gasket (503).

4. The low-resistance, noise-reducing air preheater sealing structure according to claim 1, characterized in that: The fixing assembly includes a first fixing ring (601) mounted on two sets of connecting flanges (501), a second fixing ring (602) rotatably connected at one end to the first fixing ring (601), a rotating block (603) rotatably connected to the other end of the second fixing ring (602), a threaded rod (604) fixedly connected to the rotating block (603), and a hexagonal nut (605) threadedly connected to the threaded rod (604). When the second fixing ring (602) rotates until the threaded rod (604) engages with the first fixing ring (601), the other end of the second fixing ring (602) is fixed to the first fixing ring (601) through the threaded rod (604) and the hexagonal nut (605).

5. The low-resistance, noise-reducing air preheater sealing structure according to claim 4, characterized in that: Both the first fixing ring (601) and the second fixing ring (602) have trapezoidal grooves on their inner sides. When the fixing assembly is installed on the connecting flange (501), the grooves are interference-fitted with the outer surface of the connecting flange (501).

6. The low-resistance, noise-reducing air preheater sealing structure according to claim 1, characterized in that: The anti-backflow assembly includes a fixed frame (701) fixedly connected to the inside of the air preheater body (3), a return spring (702) fixedly connected to the fixed frame (701), a sealing block (703) fixedly connected to the return spring (702), a sealing ring (704) installed on the sealing block (703), and a guide rod (705) fixedly connected to one side of the sealing block (703). The sealing block (703) is slidably connected to the inside of the fixed frame (701).

7. The low-resistance, noise-reducing air preheater sealing structure according to claim 6, characterized in that: The sealing block (703) has a frustum-shaped structure, with the top surface of the frustum facing the flue gas inlet pipe (4).

8. The low-resistance, noise-reducing air preheater sealing structure according to claim 7, characterized in that: Two sets of sealing rings (704) are provided, and the two sets of sealing rings (704) are concentrically distributed on the inclined surface of the sealing block (703).

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