A new type of high-temperature-resistant and fatigue-resistant low-nitrogen boiler fan outlet flexible joint

Abstract

The utility model discloses a kind of high-temperature-resistant fatigue-resistant novel low-nitrogen boiler fan outlet flexible joints, including the upper flange fixed at first pipe port, the lower flange fixed at second pipe port and the soft cloth formed by multilayer material composite, the soft cloth is formed annular structure between the upper flange and the lower flange, the upper port of the annular structure is fixed with the upper flange butt joint, the lower port of the annular structure is fixed with the lower flange butt joint, so that the first pipe and the second pipe are communicated.

Description

Technical Field

[0001] This utility model relates to the field of low-NOx boiler technology, specifically to a new type of high-temperature resistant and fatigue-resistant low-NOx boiler fan outlet flexible joint. Background Technology

[0002] The main purpose of installing flexible joints at the outlet of boiler blowers is to solve the inconsistencies and difficulties in correction caused by factors such as angle, position or distance during pipeline installation. It can also reduce vibration and noise, and ensure the safe operation and stability of the blower.

[0003] Due to practical needs, the applicant modified the low-NOx boiler. Before the modification, the air temperature at the blower inlet was between -5℃ and 40℃ (normal temperature). After the modification, some high-temperature flue gas was introduced into the blower inlet, causing the inlet temperature to reach 60℃ to 90℃. This caused the blower's flexible joint to become brittle and leak, as well as cracks caused by the combined effects of vibration and high temperature. The damage to the flexible joint will directly affect the boiler operation, and the existing flexible joint configuration is obviously no longer suitable.

[0004] Therefore, it is essential to develop a flexible fan joint suitable for modified low-NOx boilers. Utility Model Content

[0005] The purpose of this invention is to provide a new type of low-NOx boiler fan outlet flexible joint that is resistant to high temperatures and fatigue, suitable for pipe connections at the outlet of Cochrane boiler fans, enabling long-term stable operation of the fan outlet flexible joint under high temperature and high load conditions, and significantly improving its service life and heat resistance.

[0006] The technical solution adopted by this utility model to solve its technical problem is to propose a new type of low-NOx boiler fan outlet flexible joint that is resistant to high temperature and fatigue. It includes an upper flange fixed at the first pipe port, a lower flange fixed at the second pipe port, and a soft cloth formed by multi-layer composite materials. The soft cloth is wrapped around the upper flange and the lower flange to form an annular structure. The upper port of the annular structure is connected and fixed to the upper flange, and the lower port of the annular structure is connected and fixed to the lower flange, so that the first pipe and the second pipe are connected.

[0007] Furthermore, the soft fabric is formed by at least a first layer, a second layer and a third layer, with at least one third layer located in the middle, the second layer disposed on both sides of the third layer, and the first layer disposed on the outer side of the second layer.

[0008] Furthermore, the soft fabric is formed by a composite of a first layer, a second layer, a third layer, and an inner layer, with the inner layer located in the middle, the third layer disposed on both sides of the inner layer, the second layer being composited on the outer side of the third layer, and the first layer being composited on the outer side of the second layer.

[0009] Furthermore, the inner layer is made of lightweight refractory material.

[0010] Furthermore, the first and second layers are made of high-temperature resistant materials, and the third layer is made of heat-insulating materials.

[0011] Furthermore, the relative height between the upper flange and the lower flange is the same as the height of the annular structure, and the annular wall structure of the annular structure is flat.

[0012] Furthermore, it also includes a clamping assembly, which includes an upper clamping member and a lower clamping member. The upper end of the annular structure is fixed to the upper flange via the upper clamping member, and the lower end of the annular structure is fixed to the lower flange via the lower clamping member.

[0013] Furthermore, the upper flange includes an upper flange plate fixed to the first pipe and an upper mating ring perpendicular to the upper flange plate. The upper end of the annular structure is sleeved on the upper mating ring, and the upper pressing member presses the inner side of the upper end of the annular structure against the outer side of the upper mating ring.

[0014] Furthermore, the lower flange includes a lower flange plate fixed to the second pipe and a lower mating ring perpendicular to the lower flange plate. The lower end of the annular structure is sleeved on the lower mating ring, and the lower pressing member presses the inner side of the lower end of the annular structure against the outer side of the lower mating ring.

[0015] Furthermore, the ends of the soft cloth are joined together or overlapped to form the annular structure, and the annular wall of the annular structure is sealed, so that the first tube and the second tube are connected through the annular structure.

[0016] Preferably, the first layer constituting the soft cloth is a material with sealing properties. The first layer located inside the ring structure overlaps and joins at the joint, and the first layer located outside the ring structure overlaps and joins at the joint. The overlapping parts are glued together or sewn together with heat-resistant adhesive. The second layer located inside the ring structure joins end to end at the joint, and the second layer located outside the ring structure joins end to end at the joint. The third layer is made of fibrous heat-insulating material deployed in a ring shape, and the fourth layer is made of fibrous lightweight refractory material deployed in a ring shape. Finally, a ring structure with a sealed ring wall is formed.

[0017] It is feasible to overlap and sew or glue the joints of the soft fabric to seal the ring wall of the ring structure.

[0018] The beneficial effects of this utility model are as follows: This utility model proposes a novel high-temperature resistant and fatigue-resistant low-NOx boiler fan outlet flexible joint, which is composed of multiple layers of composite materials to form a high-temperature resistant, heat-insulating and fire-resistant soft cloth. The soft cloth and flange are used to construct the fan outlet flexible joint, realizing the connection between the fan outlet and inlet. This enables the fan outlet flexible joint to operate stably for a long time under high temperature and high load environments, significantly improving its service life and heat resistance.

[0019] In this application, a clamping assembly is used to press the soft cloth onto the flange port, ensuring a tight bond between the layers of the soft cloth and providing overall strength.

[0020] In this application, a ring structure is formed by soft cloth, with the two ends of the ring structure connected to the fan outlet and inlet respectively, and clamped by a clamping component, which facilitates disassembly and installation and ensures the stability of the connection.

[0021] In this application, the ends of the soft cloth are joined together or overlapped to form a ring structure. The joint ensures a sealing effect, keeps the ring wall of the ring structure sealed, and ensures the sealing between the fan outlet and inlet. Attached Figure Description

[0022] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the present invention. In these drawings, similar reference numerals are used to denote similar elements. The drawings described below are some embodiments of the present invention, but not all embodiments. Other drawings will be readily available to those skilled in the art based on these drawings without any inventive effort.

[0023] Figure 1 This is a schematic diagram illustrating the application of a novel high-temperature resistant and fatigue-resistant low-NOx boiler fan outlet flexible joint according to an embodiment of this utility model. Figure 2 This is a cross-sectional schematic diagram of a novel high-temperature resistant and fatigue-resistant low-NOx boiler fan outlet flexible joint according to an embodiment of the present invention. Figure 3 This is a schematic diagram of a single-sided cross-section of a flexible joint; Figure 4 for Figure 3 A partial schematic diagram; Figure 5 This is a top view of a flange. Figure 6 This is a top view of another type of flange.

[0024] In the diagram: 1. First pipe; 2. Soft cloth; 3. Second pipe; 4. Inner layer; 5. Upper pressure component; 6. Lower pressure component; 7. Upper flange; 8. Lower flange; 21. First layer; 22. Second layer; 23. Third layer; 31. Air inlet pipe; 32. Secondary smoke return pipe; 71. Upper flange; 72. Connecting ring. Detailed Implementation

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model and the prior art, the specific implementation methods of this utility model will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without creative effort. Furthermore, the design orientation only indicates the relative positional relationship between the components, not the absolute positional relationship.

[0026] This utility model embodiment provides a novel high-temperature resistant and fatigue-resistant low-NOx boiler fan outlet flexible joint. Please refer to [link / reference]. Figures 1-6 It mainly includes an upper flange 7 fixed at the port of the first pipe 1, a lower flange 8 fixed at the port of the second pipe 3, and a soft cloth 2 formed by multi-layer composite materials. The soft cloth 2 is wrapped around the upper flange 7 and the lower flange 8 to form a ring structure. The upper port of the ring structure is connected and fixed to the upper flange 7, and the lower port of the ring structure is connected and fixed to the lower flange 8, so that the first pipe 1 and the second pipe 3 are connected.

[0027] The flexible joint at the blower outlet in this application is applicable to pipe connections at the blower outlet of a Cochrane boiler; its layout can be found in [reference needed]. Figure 1 The first pipe 1 can be the air supply pipe of the boiler fan, and the second pipe 3 can be the air inlet docking port. The boiler fan air inlet pipe 31 and the secondary flue pipe 32 can be extended thereafter. The fan outlet flexible joint is used to connect the first pipe 1 and the second pipe 3.

[0028] Among them, the port of the first pipe 1 is the air supply port, and the port of the second pipe 3 is the air inlet port. Generally speaking, the air supply port is located directly above the air inlet port.

[0029] The upper flange 7 is fixedly installed at the air supply port, and the lower flange 8 is fixedly installed at the air inlet port. The soft cloth 2 is wrapped between the two flanges to form a ring structure. The ring wall of the ring structure is in a sealed state, connecting the air supply port and the air inlet port.

[0030] It is understandable that the height of the flange is generally fixed. Therefore, the dimensions of the upper flange 7 and the lower flange 8 can be considered fixed and do not affect the relative height between the air supply port and the air inlet port, and thus do not affect the height of the soft cloth 2. However, the dimensions of the flange are selected based on the air supply port and the air inlet port, which affects the length of the soft cloth 2. The dimensions of the soft cloth 2 can be adjusted according to actual needs so that the final ring structure meets the actual requirements.

[0031] In this application, the height of the soft cloth 2 is the same as the height of the ring structure, and the length of the soft cloth 2 should be at least the circumference of the ring structure to ensure that the ring structure can be fitted onto the flange for fixation.

[0032] Since the ring structure formed by the soft cloth 2 serves as a connection and contains a high-temperature airflow, the ring structure tends to have a flat ring wall to avoid affecting or interfering with the flow of the high-temperature airflow and to ensure uniform heating of the ring wall.

[0033] In one specific embodiment, taking the air supply port located directly above the air inlet port as an example, the height of the soft cloth 2 can be the same as the relative height between the two ports, so that the ring wall structure formed by the soft cloth 2 is flat in the vertical direction.

[0034] It should be clarified that a smooth ring wall structure means that the ring wall has no wrinkles. For example, when the ring structure is cylindrical, the ring wall is cylindrical and can be considered to have a smooth structure; when the ring structure is prismatic, the ring wall is composed of multiple planes and can be considered to have a smooth structure.

[0035] In practice, the height of the soft cloth 2 can be determined based on the relative height between the upper flange 7 and the lower flange 8. That is, the relative height between the upper flange 7 and the lower flange 8 is the same as the height of the ring structure, and the ring wall structure of the ring structure is flat.

[0036] In this application, the soft cloth 2 is wrapped around the upper flange 7 and the lower flange 8 to form a ring structure. The soft cloth 2 can be joined end to end or overlapped to form a ring structure, so that the ring wall of the ring structure is sealed, ensuring the connection between the first pipe 1 and the second pipe 3 without leakage.

[0037] In the embodiments of this application, the soft cloth 2 is formed by at least a first layer 21, a second layer 22 and a third layer 23. The specific structure is as follows: the third layer 23 is located in the middle, the second layer 22 is provided on both sides of the third layer 23, and the first layer is composited on the outer side of the second layer 22.

[0038] In a preferred embodiment, the soft fabric 2 is formed by a composite of a first layer 21, a second layer 22, a third layer 23, and an inner layer 4. Specifically, the inner layer 4 is located in the middle, with the third layer 23 on each side of the inner layer 4. The outer sides of the third layer are composited with the second layer 22, and the outer sides of the second layer 22 are composited with the first layer 21. Figure 4 As shown in the image.

[0039] Specifically, the inner layer 4 is made of lightweight refractory material, the first layer 21 and the second layer 22 are made of high temperature resistant material, and the third layer 23 is made of heat insulation material.

[0040] Taking the soft cloth 2, which is composed of seven layers of materials, as an example, the first layer 21 and the second layer 22 are high temperature resistant cloth, the third layer 23 is heat insulation fiber cloth, and the inner layer 4 is fire resistant cloth.

[0041] For example, high-temperature resistant cloth: Teflon-coated fiberglass cloth can be used for long-term application within a wide temperature range of -60℃ to +300℃, preventing material embrittlement and cracking. Thermal insulation fiber cloth: Composed of ceramic fibers and a certain proportion of organic fibers, it features high temperature resistance, low thermal conductivity, and thermal shock resistance, preventing air leakage caused by mixed high-temperature flue gas. Fire-resistant cloth: Composed of aluminosilicate fibers, it is a fibrous, lightweight refractory material with high tensile strength.

[0042] Specifically, the details of each layer of materials: High-temperature resistant fabric: Temperature range: It can be used for a long time in a wide temperature range of -60℃ to +300℃, and will not age or crack after working at an ultra-high temperature of +360℃ for 120 hours.

[0043] Material properties: It has weather resistance, non-adhesive mechanical properties, good electrical insulation and chemical resistance.

[0044] Application areas: Used for anti-sticking inner lining gaskets, welding cloth for plastic products, insulating materials, and heat-resistant cladding layers, etc.

[0045] Thermal insulation fiber cloth: Temperature range: Continuous use temperature up to 1000℃, short-term use temperature up to 1260℃.

[0046] Low thermal conductivity: It has good thermal insulation performance and can effectively reduce heat transfer.

[0047] Material properties: thermal shock resistance to withstand rapid temperature changes, low heat capacity with minimal heat absorption or release during heating or cooling, excellent high-temperature insulation, high strength, and corrosion resistance.

[0048] Application areas: thermal insulation materials for industrial kilns, pipe coverings, fire protection, and electrical applications.

[0049] Fire-resistant cloth: Temperature range: 950-1400℃, different grades of products can be used for a long time at the corresponding high temperature.

[0050] Material properties: It has high heat resistance, low electrical conductivity, low heat capacity, high strength and good chemical stability.

[0051] Application areas: High-temperature insulation materials for aerospace, steel, petrochemical and other industries; also used for heat insulation and fireproofing of electrical components, making high-temperature gaskets, and as raw materials for modules and folding blocks.

[0052] Based on the multi-layered composite structure of the soft cloth 2 and the characteristics of each layer of material, various embodiments are possible, so that the soft cloth 2 is composited into a ring structure and the sealing of the ring wall is guaranteed.

[0053] In a preferred embodiment, the first layer 21 constituting the soft cloth 2 is a material with sealing properties. The first layer 21 located inside the annular structure overlaps and joins at the joint, and the first layer 21 located outside the annular structure overlaps and joins at the joint. The overlapping parts are glued together or sewn together with heat-resistant adhesive. The second layer 22 located inside the annular structure is joined end to end at the joint, and the second layer 22 located outside the annular structure is joined end to end at the joint. The third layer 23 is made of fibrous heat-insulating material deployed in an annular form, and the inner layer 4 is made of fibrous lightweight refractory material deployed in an annular form. Finally, an annular structure with a sealed annular wall is formed.

[0054] As a feasible embodiment, the joints of the soft cloth 2 are overlapped and sewn or overlapped and pasted to make the ring wall of the ring structure sealed.

[0055] In the embodiments of this application, the connection between the air supply port and the air inlet port is achieved based on the ring structure and the flange structure. The ring structure and the flange structure are fixedly connected, and the sealing effect between the two should also be guaranteed. Therefore, a pressing component can be set to press the ring structure onto the flange structure.

[0056] In one specific embodiment, the clamping assembly may include an upper clamping member 5 and a lower clamping member 6. The upper end of the annular structure is fixed to the upper flange 7 via the upper clamping member 5, and the lower end of the annular structure is fixed to the lower flange 8 via the lower clamping member 6.

[0057] When applied to ports with different structural forms, adaptive adjustments can be made. However, it should be clear that both the air supply port and the air inlet port are closed ports, hence they can be called ring ports. The corresponding flange structure is also ring-shaped, specifically ring-shaped flanges, rectangular flanges, etc.

[0058] In specific implementation, the upper flange 7 includes an upper flange 71 fixed to the first pipe 1 and an upper mating ring 72 perpendicular to the upper flange 71. The upper end of the ring structure is sleeved on the upper mating ring 72, and the upper pressure member 5 presses the inner side of the upper end of the ring structure against the outer side of the upper mating ring 72.

[0059] The lower flange 8 includes a lower flange plate that is fixed to the second pipe 3 and a lower mating ring that is perpendicular to the lower flange plate. The lower end of the ring structure is sleeved on the lower mating ring, and the lower pressing member 6 presses the inner side of the lower end of the ring structure against the outer side of the lower mating ring.

[0060] Based on the ring-shaped definition of the flange structure, the upper mating ring 72 can be circular, such as... Figure 6 As shown, it can also be rectangular, such as... Figure 5 As shown.

[0061] For example, the clamping assembly may include an upper clamp and a lower clamp. The clamp can be applied to a ring-shaped flange structure, directly clamping the upper end of the ring structure formed by the soft cloth 2 onto the upper flange 7, and the lower end directly onto the lower flange 8. Taking the upper flange as an example, the upper mating ring 72 is ring-shaped, which can be adapted to the ring-shaped clamp to achieve a clamping and fixing effect, ensuring the sealing effect between the soft cloth 2 and the upper flange 7.

[0062] For example, the clamping assembly may include an upper clamping plate and a lower clamping plate. The clamping plates are suitable for rectangular flange structures, directly clamping the upper end of the ring structure formed by the soft cloth 2 onto the upper flange 7 and the lower end onto the lower flange 8. Taking the upper flange as an example, the upper mating ring 72 is rectangular and can be fitted with four clamping plates to achieve a clamping and fixing effect, ensuring the sealing effect between the soft cloth 2 and the upper flange 7.

[0063] In this application, the structural forms of the air supply port and the air inlet port should be consistent. If the air supply port is circular, then the air inlet port should also be circular. The flange used can be as follows: Figure 6 If the air supply port is rectangular, then the air inlet port should also be rectangular, and the flange used can be as follows: Figure 6 .

[0064] In one specific embodiment, taking a rectangular port as an example, the flexible joint duct has dimensions of 400mm (length) × 300mm (width) × 200mm (height). It can be constructed from a 7-layer high-temperature resistant composite flexible material, 200mm + 15mm high × 1500mm long. The outer two layers of high-temperature resistant fabric are 400mm + 30mm high × 1500mm long, the inner two layers of ceramic fiber fabric are 400mm + 30mm high × 1500mm long, and the core layer is a ceramic fiber blanket 200mm + 15mm high × 1500mm long. A pressing assembly can be constructed from a 400mm long × 300mm wide stainless steel frame, with two 6mm thick pressure strips installed on each of the four sides to form upper and lower pressing components for fixation.

[0065] Preferably, the high-temperature resistant flexible joint composite layer, that is, the soft cloth 2 should be increased by 15mm in height on the original basis to ensure that the flexible joint has sufficient vibration margin.

[0066] The boiler fan outlet flexible joint design proposed in this application is highly practical. Firstly, by optimizing the material formulation and processing technology, the stability and durability of the flexible joint are achieved under high-temperature environments, effectively solving the problems of easy damage and short service life of existing boiler fan outlet flexible joints under high-temperature and high-load conditions, thus improving the overall operating efficiency and stability of the equipment. Secondly, the new structural design allows the flexible joint to maintain good sealing and anti-wear performance even under high loads; at the same time, it saves on replacement costs and reduces maintenance costs.

[0067] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0068] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific embodiments of the present invention are limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the protection scope of the present invention.

Claims

1. A novel low-NOx boiler fan outlet flexible joint with high temperature resistance and fatigue resistance, characterized in that, It includes an upper flange (7) fixed at the port of the first pipe (1), a lower flange (8) fixed at the port of the second pipe (3), and a soft cloth (2) formed by multi-layer material composite. The soft cloth is wrapped around the upper flange (7) and the lower flange (8) to form an annular structure. The upper port of the annular structure is connected and fixed to the upper flange (7), and the lower port of the annular structure is connected and fixed to the lower flange (8), so that the first pipe (1) and the second pipe (3) are connected.

2. The high-temperature resistant and fatigue-resistant novel low-NOx boiler fan outlet flexible joint according to claim 1, characterized in that, The soft cloth (2) is formed by at least a first layer (21), a second layer (22) and a third layer (23), with the third layer (23) located in the middle, and the second layer (22) respectively provided on both sides of the third layer (23), and the first layer respectively composited on the outer side of the second layer (22).

3. The high-temperature resistant and fatigue-resistant novel low-NOx boiler fan outlet flexible joint according to claim 1, characterized in that, The soft cloth (2) is formed by a composite of a first layer (21), a second layer (22), a third layer (23) and an inner layer (4). The inner layer (4) is located in the middle, and the third layer (23) is provided on both sides of the inner layer (4). The second layer (22) is composited on the outer side of the third layer, and the first layer (21) is composited on the outer side of the second layer (22).

4. The high-temperature resistant and fatigue-resistant novel low-NOx boiler fan outlet flexible joint according to claim 3, characterized in that, The inner layer (4) is made of lightweight refractory material.

5. A novel low-NOx boiler fan outlet flexible joint with high temperature resistance and fatigue resistance according to claim 2 or 3, characterized in that, The first layer (21) and the second layer (22) are made of high temperature resistant materials, and the third layer (23) is made of heat insulation material.

6. The high-temperature resistant and fatigue-resistant novel low-NOx boiler fan outlet flexible joint according to claim 1, characterized in that, The relative height between the upper flange (7) and the lower flange (8) is the same as the height of the annular structure, and the annular wall structure of the annular structure is flat.

7. The high-temperature resistant and fatigue-resistant novel low-NOx boiler fan outlet flexible joint according to claim 1, characterized in that, It also includes a clamping assembly, which includes an upper clamping member (5) and a lower clamping member (6). The upper end of the annular structure is fixed to the upper flange (7) through the upper clamping member (5), and the lower end of the annular structure is fixed to the lower flange (8) through the lower clamping member (6).

8. The high-temperature resistant and fatigue-resistant novel low-NOx boiler fan outlet flexible joint according to claim 7, characterized in that, The upper flange (7) includes an upper flange (71) fixed to the first pipe (1) and an upper mating ring (72) perpendicular to the upper flange (71). The upper end of the ring structure is sleeved on the upper mating ring (72), and the upper pressure member (5) presses the inner side of the upper end of the ring structure against the outer side of the upper mating ring (72).

9. The high-temperature resistant and fatigue-resistant novel low-NOx boiler fan outlet flexible joint according to claim 7, characterized in that, The lower flange (8) includes a lower flange plate that is fixed to the second pipe (3) and a lower mating ring that is perpendicular to the lower flange plate. The lower end of the ring structure is sleeved on the lower mating ring, and the lower pressing member (6) presses the inner side of the lower end of the ring structure against the outer side of the lower mating ring.

10. The high-temperature resistant and fatigue-resistant novel low-NOx boiler fan outlet flexible joint according to claim 1, characterized in that, The ends of the soft cloth (2) are joined together or overlapped to form the ring structure. The ring wall of the ring structure is sealed, so that the first tube (1) and the second tube (3) are connected through the ring structure.

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