Multilayer sealing leak-proof mechanism for circulating fluidized bed boiler slag tapping pipe

Abstract

The utility model belongs to the technical field of boiler slag discharge pipe sealing, specifically disclose multilayer sealing anti -leakage mechanism of circulating fluidized bed boiler slag discharge pipe, including slag discharge pipe, the bottom of slag discharge pipe is equipped with the cold slag ware interface hopper, is equipped with the sealing assembly between slag discharge pipe and the cold slag ware interface hopper, the sealing assembly includes the connecting seat, the connecting seat cover is established in the outer wall of slag discharge pipe, the bottom end fixed connection of connecting seat has the metal corrugated section, the top end fixed connection of cold slag ware interface hopper has the connecting plate, and the metal corrugated section is in abutment with the connecting plate, is equipped with fixed assembly between connecting seat and connecting plate, the utility model discloses the setting of sealing assembly, avoid the increase of sealing surface gap due to the pre -tightening force attenuation, and the metal corrugated section absorbs displacement through compression or elongation elastic deformation, avoid the rigid connection fixed screw rod to bear overload tension, and the connecting plate and the connecting seat sealing surface tear, prevent the pipeline from the structural damage such as bending, cracking and so on because of thermal stress concentration, and then reduce the probability of leakage.

Description

Technical Field

[0001] This application relates to the field of boiler slag discharge pipe sealing technology, and more specifically, to a multi-layer sealing and leak-proof mechanism for slag discharge pipes of circulating fluidized bed boilers. Background Technology

[0002] The slag discharge pipe of a circulating fluidized bed boiler is a piping device connecting the bottom of the furnace to the slag cooler. It is mainly used to discharge the high-temperature slag (800-900℃) generated during combustion to maintain the bed thickness and combustion efficiency. Its structure is mostly made of high-temperature and wear-resistant materials (such as alloy steel or ceramic composite pipes), but it is in a high-temperature, particle erosion, and thermal expansion and contraction environment for a long time, so it must take into account both slag discharge and sealing functions.

[0003] The patent with publication number CN221300436U discloses a boiler slag discharge pipe sealing device. The upper fixing ring, lower fixing ring, upper sealing ring and lower sealing ring set in the boiler slag discharge pipe sealing device can seal the connection between the slag discharge pipe and the external interface of the slag cooler from the outside after the slag discharge pipe is connected to the external interface of the slag cooler, thereby increasing the sealing effect between the slag discharge pipe and the external interface of the slag cooler.

[0004] Although the upper fixing ring, lower fixing ring, upper sealing ring, and lower sealing ring designed in this patent can seal the connection between the slag discharge pipe and the external interface of the slag cooler from the outside after the slag discharge pipe is connected, the nested seal of the upper and lower sealing rings relies on the preload of the bolts. However, the bolts are prone to thermal relaxation under high temperature conditions, which leads to the attenuation of the preload and insufficient compression of the sealing rings. After long-term operation, gap leakage will occur due to vibration or thermal expansion and contraction, affecting the sealing performance. Utility Model Content

[0005] To address the aforementioned issues, this application provides a multi-layer sealing and leak-proof mechanism for the ash discharge pipe of a circulating fluidized bed boiler.

[0006] The multi-layer sealing and leak-proof mechanism for the ash discharge pipe of the circulating fluidized bed boiler provided in this application adopts the following technical solution:

[0007] A multi-layer sealing and leak-proof mechanism for the slag discharge pipe of a circulating fluidized bed boiler includes a slag discharge pipe, a slag cooler receiving hopper at the bottom of the slag discharge pipe, and a sealing assembly between the slag discharge pipe and the slag cooler receiving hopper.

[0008] The sealing assembly includes a connecting seat, which is installed on the outer wall of the slag discharge pipe. A metal corrugated section is fixedly connected to the bottom end of the connecting seat, and a connecting plate is fixedly connected to the top end of the slag cooler hopper. The metal corrugated section abuts against the connecting plate.

[0009] A fixing component is provided between the connector and the connecting plate.

[0010] Through the above technical solutions, the sealing components avoid the increase in the gap between the sealing surfaces due to the decrease in pre-tightening force. The metal corrugated section absorbs displacement through compression or elongation elastic deformation, avoiding overload tension on the fixed screw of the rigid connection and tearing of the sealing surfaces of the connecting plate and the connecting seat. This prevents structural damage such as bending and cracking of the pipeline due to thermal stress concentration, thereby reducing the probability of leakage.

[0011] Furthermore, the fixing components include multiple sets, each set of fixing components includes a fixing screw, the connecting seat and the connecting plate are provided with multiple insertion holes, each fixing screw is located inside the corresponding insertion hole, the outer wall of each fixing screw is fitted with a spring, and the bottom of the fixing screw is threaded with a locking nut.

[0012] Through the above technical solution, the locking nut in the fixing component maintains the axial position of the fixing screw, and the spring is compressed or extended synchronously with the displacement of the slag discharge pipe. The expansion and contraction are absorbed through elastic deformation, thus avoiding the fixing screw from bearing rigid tension.

[0013] Furthermore, the contact surfaces of the slag discharge pipe, the slag cooler hopper, the connecting seat, and the connecting plate form a sealed cavity, with multiple springs located inside the sealed cavity, and the two ends of each spring abutting against the connecting seat and the connecting plate, respectively.

[0014] Furthermore, a heat insulation ring is provided inside the sealed cavity, and a sealing ring is provided on the outside of the heat insulation ring.

[0015] Through the above technical solution, the sealing ring is compressed under the preload of the spring, filling the radial gap between the slag discharge pipe and the slag cooler hopper.

[0016] Furthermore, the outer wall of the sealing ring is fixedly connected with multiple connecting rings, and a mating ring is provided inside the sealing cavity.

[0017] Furthermore, the mating ring has multiple grooves inside, and multiple connecting rings are inserted into the corresponding grooves respectively.

[0018] Through the above technical solution, the insertion structure between the connecting ring and the groove restricts the radial displacement of the sealing ring, preventing high-temperature and high-pressure flue gas from blowing it off or squeezing it into the gap.

[0019] Furthermore, a positioning plate is fixedly connected to the top of the connecting plate, and the positioning plate is located on one side of the mating ring.

[0020] Furthermore, a positioning groove is provided on the top of the connector, and the positioning plate is inserted into the positioning groove of the connector.

[0021] In summary, this application includes at least one of the following beneficial technical effects:

[0022] (1) By setting the sealing components, this utility model avoids the increase of the gap between the sealing surfaces due to the reduction of the pre-tightening force. The metal corrugated section absorbs the displacement through compression or elongation elastic deformation, avoids the fixed screw of the rigid connection from bearing overload tension, and avoids the sealing surface of the connecting plate and the connecting seat from tearing. It also prevents the pipe from bending, cracking and other structural damage due to the concentration of thermal stress, thereby reducing the probability of leakage.

[0023] (2) In the process of thermal expansion of the slag discharge pipe, the locking nut maintains the axial position of the fixing screw, and the spring is compressed or extended synchronously with the displacement of the slag discharge pipe. The expansion and contraction are absorbed by elastic deformation, so as to avoid the fixing screw from bearing rigid tension.

[0024] (3) The sealing ring of this utility model is compressed under the pre-tightening force of the spring, filling the radial gap between the slag discharge pipe and the slag cooler hopper; at the same time, the insertion structure of the connecting ring and the trough restricts the radial displacement of the sealing ring, preventing high temperature and high pressure flue gas from blowing it off or squeezing it into the gap. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0026] Figure 2 This is a cross-sectional view of the present invention.

[0027] Figure 3 This is a partial plan view of the present invention;

[0028] Figure 4 This is an exploded view of the present invention.

[0029] Explanation of reference numerals in the attached drawings: 1. Slag discharge pipe; 2. Slag cooler hopper; 3. Connecting seat; 4. Connecting plate; 5. Corrugated metal section; 6. Fixing screw; 7. Locking nut; 8. Spring; 9. Heat insulation ring; 10. Sealing ring; 11. Connecting ring; 12. Positioning plate; 13. Mating ring. Detailed Implementation

[0030] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0031] Reference Figures 1-4 The multi-layer sealing and leak-proof mechanism of the slag discharge pipe of the circulating fluidized bed boiler includes a slag discharge pipe 1, a slag cooler hopper 2 at the bottom of the slag discharge pipe 1, and a sealing assembly between the slag discharge pipe 1 and the slag cooler hopper 2.

[0032] The sealing assembly includes a connecting seat 3, which is covered on the outer wall of the slag discharge pipe 1. A metal corrugated section 5 is fixedly connected to the bottom end of the connecting seat 3, and a connecting plate 4 is fixedly connected to the top end of the slag cooler receiving hopper 2. The metal corrugated section 5 abuts against the connecting plate 4.

[0033] A fixing component is provided between the connecting base 3 and the connecting plate 4.

[0034] When the slag discharge pipe 1 is connected to the slag cooler receiving hopper 2, the connecting seat 3 is covered on the outer wall of the slag discharge pipe 1, and the corrugated metal section 5 at its bottom end abuts against the connecting plate 4 at the top of the slag cooler receiving hopper 2. Multiple insertion holes are opened inside the connecting seat 3 and the connecting plate 4 through the fixing screw 6. A spring 8 is sleeved on the outer wall of each fixing screw 6. Then, the locking nut 7 is threaded and tightened at the bottom of the fixing screw 6, so that the spring 8 is in a compressed state and applies a continuous pre-tightening force to the connecting seat 3 and the connecting plate 4, ensuring that the corrugated metal section 5 and the connecting plate 4 fit tightly together.

[0035] When the boiler experiences drastic temperature changes during start-up or shutdown, or when long-term high-temperature operation causes material creep, the metal corrugated section 5 dynamically compensates for the axial displacement of the slag discharge pipe 1 through elastic deformation, thus avoiding stress concentration caused by rigid connection.

[0036] By setting up the sealing components, the gap between the sealing surfaces is prevented from increasing due to the reduction of pre-tightening force. The metal corrugated section 5 absorbs displacement through compression or elongation elastic deformation, preventing the fixed screw 6 of the rigid connection from bearing overload tension and the sealing surfaces of the connecting plate 4 and the connecting seat 3 from tearing. This prevents structural damage such as bending and cracking of the pipeline due to thermal stress concentration, thereby reducing the probability of leakage.

[0037] Reference Figures 1-4 The fixing components include multiple sets, each set of fixing components includes fixing screws 6, the connecting seat 3 and the connecting plate 4 are provided with multiple insertion holes, each fixing screw 6 is located inside the corresponding insertion hole, each fixing screw 6 is fitted with a spring 8 on its outer wall, and the bottom of the fixing screw 6 is threaded with a locking nut 7.

[0038] Multiple sets of fixing screws 6 pass through the insertion holes of the connecting seat 3 and the connecting plate 4. After a spring 8 is fitted onto the outer wall of the screw, it is tightened with a locking nut 7, so that the spring 8 is in a compressed state and generates a preload. The locking nut 7 is connected to the bottom of the fixing screw 6 by a thread, and its tightening degree directly controls the compression of the spring 8, thereby adjusting the preload between the connecting seat 3 and the connecting plate 4.

[0039] When the locking nut 7 is tightened, the spring 8 is compressed and exerts a thrust on the connecting seat 3 and the connecting plate 4, bringing the metal corrugated section 5 into close contact with the connecting plate 4 to form an initial sealing pressure; when the locking nut 7 is loosened, the elastic force of the spring 8 is released, and the preload decreases.

[0040] During the thermal expansion of the slag discharge pipe 1, the locking nut 7 maintains the axial position of the fixing screw 6, and the spring 8 compresses or extends synchronously with the displacement of the slag discharge pipe 1. The expansion and contraction are absorbed through elastic deformation to prevent the fixing screw 6 from bearing rigid tension. When the temperature decreases and the slag discharge pipe 1 contracts, the spring 8 pushes the connecting seat 3 back to its original position under the action of elastic restoring force. At this time, the locking nut 7 prevents the fixing screw 6 from loosening and ensures that the preload of the spring 8 continues to act on the sealing surface.

[0041] Reference Figures 3-4 The slag discharge pipe 1, the slag cooler receiving hopper 2, the connecting seat 3 and the connecting plate 4 form a sealed cavity at their contact surfaces. Multiple springs 8 are located inside the sealed cavity, and the two ends of each spring 8 abut against the connecting seat 3 and the connecting plate 4 respectively.

[0042] Reference Figures 2-4 The sealing cavity is provided with a heat insulation ring 9 inside, and a sealing ring 10 is provided on the outside of the heat insulation ring 9. Multiple connecting rings 11 are fixedly connected to the outer wall of the sealing ring 10. The sealing cavity is provided with a mating ring 13 inside, and multiple grooves are opened inside the mating ring 13. Multiple connecting rings 11 are respectively inserted into the corresponding grooves.

[0043] When the slag discharge pipe 1 is connected to the slag cooler receiving hopper 2, the positioning plate 12 is inserted into the positioning groove of the connecting seat 3 to facilitate the installation of the fixing screw 6. The positioning plate 12 is a flexible structure.

[0044] The heat insulation ring 9 uses a low thermal conductivity material (such as ceramic fiber) to block the heat transfer of high-temperature slag, reducing the internal temperature of the sealing cavity to the tolerance range of the sealing ring 10 and preventing the sealing ring 10 from failing due to high-temperature aging. The sealing ring 10 is compressed under the preload of the spring 8, filling the radial gap between the slag discharge pipe 1 and the slag cooler hopper 2; at the same time, the insertion structure of the connecting ring 11 and the trough restricts the radial displacement of the sealing ring 10, preventing high-temperature and high-pressure flue gas from blowing it off or squeezing it into the gap.

[0045] Both the connecting ring 11 and the sealing ring 10 are flexible structures. During installation, the connecting ring 11 needs to be manually inserted into the groove of the sealing ring 10.

[0046] When the slag discharge pipe 1 thermally expands, the positioning plate 12 is squeezed in the positioning groove, allowing the connecting seat 3 and the connecting plate 4 to produce axial relative displacement.

[0047] The heat insulation ring 9 is made of ceramic fiber, and the sealing ring 10 is made of flexible graphite composite material. Both of these materials can withstand certain high temperatures.

[0048] Reference Figures 1-4 A positioning plate 12 is fixedly connected to the top of the connecting plate 4. The positioning plate 12 is located on one side of the mating ring 13. A positioning groove is provided on the top of the connecting seat 3. The positioning plate 12 is inserted into the positioning groove of the connecting seat 3.

[0049] Working Principle: During installation, the slag discharge pipe 1 is inserted into the slag cooler hopper 2, with the connecting seat 3 covering the outer wall of the slag discharge pipe 1. The bottom corrugated metal section 5 abuts against the connecting plate 4 at the top of the slag cooler hopper 2. Multiple sets of fixing screws 6 pass through the insertion holes of the connecting seat 3 and the connecting plate 4. After installing the spring 8, the locking nut 7 is tightened, compressing the spring 8 and applying a preload to the connecting seat 3 and the connecting plate 4, ensuring a tight fit between the corrugated metal section 5 and the connecting plate 4. During operation, when the boiler starts or stops, or load fluctuations cause drastic temperature changes in the slag discharge pipe 1 resulting in axial expansion, or prolonged high temperatures cause material creep, the corrugated metal section 5 dynamically compensates for the displacement through elastic compression or elongation, preventing the fixing screws 6 from breaking due to rigid tension. Simultaneously, the spring 8 expands and contracts synchronously with the displacement of the slag discharge pipe 1, maintaining the preload on the sealing surface, and the locking nut 7 prevents the screws from loosening. Inside the sealed cavity, the heat insulation ring 9 blocks the heat of the high-temperature slag, reducing the temperature of the sealed cavity to the tolerance range of the sealing ring 10 and preventing it from aging at high temperature. The sealing ring 10 is compressed under the pre-tightening force of the spring 8, filling the radial gap between the slag discharge pipe 1 and the slag cooler hopper 2 to form a sealing barrier. Its outer wall connecting ring 11 is inserted into the groove of the mating ring 13 to limit the radial displacement of the sealing ring 10 and prevent it from being blown off by the flue gas.

[0050] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A multi-layer sealing and leak-proof mechanism for the slag discharge pipe of a circulating fluidized bed boiler, characterized in that, include: Slag discharge pipe (1), the bottom of the slag discharge pipe (1) is provided with a slag cooler receiving hopper (2), and a sealing assembly is provided between the slag discharge pipe (1) and the slag cooler receiving hopper (2); The sealing assembly includes a connecting seat (3), which covers the outer wall of the slag discharge pipe (1). A metal corrugated section (5) is fixedly connected to the bottom end of the connecting seat (3), and a connecting plate (4) is fixedly connected to the top end of the slag cooler receiving hopper (2). The metal corrugated section (5) abuts against the connecting plate (4). A fixing component is provided between the connecting seat (3) and the connecting plate (4).

2. The multi-layered leak-proof mechanism of the slag tap of the circulating fluidized bed boiler according to claim 1, characterized in that: The fixing components include multiple sets, each set of fixing components includes a fixing screw (6), the connecting seat (3) and the connecting plate (4) are provided with multiple insertion holes, each fixing screw (6) is located inside the corresponding insertion hole, the outer wall of each fixing screw (6) is fitted with a spring (8), and the bottom of the fixing screw (6) is threaded with a locking nut (7).

3. The multi-layered leak-proof mechanism of the slag tap of the circulating fluidized bed boiler according to claim 2, characterized in that: The contact surfaces of the slag discharge pipe (1), the slag cooler hopper (2), the connecting seat (3), and the connecting plate (4) form a sealed cavity. Multiple springs (8) are located inside the sealed cavity, and the two ends of each spring (8) abut against the connecting seat (3) and the connecting plate (4) respectively.

4. The multi-layered leak-proof mechanism of the slag tap of the circulating fluidized bed boiler according to claim 3, characterized in that: The sealed cavity is provided with a heat insulation ring (9) inside, and a sealing ring (10) is provided on the outside of the heat insulation ring (9).

5. The multi-layered leak-proof mechanism of the slag tap of the circulating fluidized bed boiler according to claim 4, characterized in that: The outer wall of the sealing ring (10) is fixedly connected with multiple connecting rings (11), and the sealing cavity is provided with a mating ring (13).

6. The multi-layered leak-proof mechanism of the slag tap of a circulating fluidized bed boiler according to claim 5, characterized in that: The mating ring (13) has multiple grooves inside, and the multiple connecting rings (11) are respectively inserted into the corresponding grooves.

7. The multi-layered leak-proof mechanism of the slag tap of the circulating fluidized bed boiler according to claim 1, characterized in that: A positioning plate (12) is fixedly connected to the top of the connecting plate (4), and the positioning plate (12) is located on one side of the mating ring (13).

8. The multi-layered leak-proof mechanism of the circulating fluidized bed boiler slag tap according to claim 7, characterized in that: The top of the connecting seat (3) is provided with a positioning groove, and the positioning plate (12) is inserted into the positioning groove of the connecting seat (3).

Images