Pi-shaped boiler with split type flue
By using a split design and flexible connection with non-metallic expansion joints, combined with the ash hopper support truss and support leg assembly, the problems of weld cracking and load transfer in the flue ash hopper of the Π-type boiler are solved, ensuring the safe and stable operation of the boiler.
Patent Information
- Application Number
- CN202520020780.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-06
- Publication Date
- 2026-02-24
- Estimated Expiration
- 2035-01-06
AI Technical Summary
In existing Π-type boilers, the welded connection between the flue ash hopper and the rear vertical shaft is prone to cracking due to thermal expansion mismatch, leading to the risk of the ash hopper falling off. Furthermore, load transfer makes it difficult to select the appropriate wall-mounted tubes, affecting the safe operation of the boiler.
The design adopts a split structure, with the rear shaft and the flue ash hopper flexibly connected by a non-metallic expansion joint. Combined with the ash hopper support truss and outrigger assembly, it provides movable support and limit, avoids weld cracking, and reduces the load on the rear shaft.
It effectively prevents the flue ash hopper from falling off, reduces the difficulty of selecting wall-mounted pipes, and ensures the safety and stability of boiler operation.
Smart Images
Figure CN223939465U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of power plant boiler equipment, specifically relating to a Π-type boiler with a split flue. Background Technology
[0002] In the Π-type boiler structure of a power plant, the rear shaft, as a key structure, plays a crucial role in circulating flue gas and absorbing heat. To effectively collect and store ash from the flue gas and reduce wear and blockage of downstream equipment, a flue ash hopper is typically designed and integrated with the rear shaft, with the ash hopper welded to the bottom of the rear shaft. This design utilizes the structure of the rear shaft to bear the load of the flue ash hopper, reducing the need for additional support structures.
[0003] However, with the rapid development of new energy sources, power plant boilers face higher demands for peak-shaving capacity, requiring them to operate at lower loads. This leads to a significant reduction in flue gas velocity within the rear shaft and a continuous increase in ash accumulation in the flue ash hopper. Currently, the load on the flue ash hopper is transferred sequentially through the wall-mounted pipes and hangers of the rear shaft to the boiler steel frame roof. Consequently, the stress on the rear shaft wall-mounted pipes and the boiler steel frame roof increases during boiler operation, making design and selection difficult and challenging to find a wall-mounted pipe model that meets the boiler's safe operation requirements. Furthermore, the welded joints connecting the flue ash hopper and the rear shaft can crack due to excessive thermal or mechanical stress, potentially causing the flue ash hopper to fall from the rear shaft and resulting in a serious safety accident.
[0004] A patent currently discloses a connection device for a boiler's rear shaft and ash hopper, which improves the load-bearing capacity at the connection point by adding protective plates to the rear shaft and ash hopper. However, this patent does not consider the expansion that occurs when the rear shaft and ash hopper are exposed to high temperatures during use. Since the expansion rates of the rear shaft and ash hopper are often different, the protective plates may become misaligned or loose due to the pressure from the expansion, posing a risk of the ash hopper falling off even after the weld cracks. Furthermore, this patent does not solve the problem of difficulty in selecting the wall-mounted pipe for the rear shaft due to load transfer. Therefore, there is an urgent need for a Π-type boiler that can solve the above problems. Utility Model Content
[0005] The purpose of this utility model is to provide a Π-type boiler with a split flue, addressing the aforementioned shortcomings. This aims to solve the current problems of flue ash hoppers falling from the rear shaft due to weld cracking and the difficulty in selecting wall-mounted pipes due to load transfer from the flue ash hopper. To achieve the above objectives, this utility model provides the following technical solution:
[0006] A Π-shaped boiler with a split flue includes a rear vertical shaft, a flue ash hopper, a non-metallic expansion joint, two support leg assemblies, and two ash hopper support trusses. The flue ash hopper is located below the rear vertical shaft, and the rear vertical shaft and the flue ash hopper are flexibly connected by the non-metallic expansion joint. The two support leg assemblies are located at the bottom of the flue ash hopper and are arranged opposite each other along a first direction. Each support leg assembly includes several legs arranged sequentially along a second direction. The two ash hopper support trusses extend along the second direction and are respectively fitted to two...
[0007] Below the outrigger assembly; the top of the ash hopper support truss is provided with several supports along the second direction, and each support corresponds to one outrigger in the corresponding outrigger assembly; the outrigger is movably fitted onto the corresponding support; the support is used to provide movable support for the outrigger and limit its movement to prevent the outrigger from falling out of the support; the length direction of the rear shaft is the third direction, and both the first direction and the second direction are perpendicular to the third direction, and the first direction and the second direction are perpendicular to each other.
[0008] Furthermore, the support is provided with a supporting top plate; the support leg includes a connecting base and a slider; the connecting base is located at the bottom of the support leg; the top of the slider is connected to the center of the bottom surface of the connecting base; the slider has a contact bottom surface for sliding contact with the top surface of the supporting top plate; the support is also provided with a limiting component, which is used to limit the displacement range of the support leg on the supporting top plate along the first direction and / or the second direction.
[0009] Furthermore, the contact bottom surface of the slider is a downwardly convex arc surface.
[0010] Furthermore, the limiting component includes a plurality of first limiting members; the plurality of first limiting members are disposed opposite to each other on both sides of the top surface of the supporting top plate along the second direction, for providing limiting in the second direction and the third direction for connecting the chassis.
[0011] Furthermore, the first limiting member is an inverted L-shaped limiting block; the inverted L-shaped limiting block includes a first side and a second side; the first side is disposed on the top surface of the supporting top plate and extends along a third direction; one end of the second side is connected to the top of the first side, and the other end extends along a second direction toward the side close to the connecting chassis.
[0012] Furthermore, the limiting component also includes a plurality of second limiting members; the plurality of second limiting members are disposed opposite to each other on both sides of the top surface of the supporting top plate along the first direction, and the top surface height of the second limiting members is lower than the bottom surface height of the connecting chassis; the second limiting members are used to limit the displacement of the slider in the first direction on the supporting top plate.
[0013] Furthermore, the outlet diameter of the rear shaft is the same as the inlet diameter of the flue ash hopper.
[0014] Furthermore, the ash hopper support truss is a steel truss made of Q355B steel.
[0015] The beneficial effects of this utility model are:
[0016] This utility model discloses a Π-type boiler with a split flue, belonging to the technical field of power plant boiler equipment. It includes a rear vertical shaft, a flue ash hopper, a non-metallic expansion joint, two support leg assemblies, and two ash hopper support trusses. The flue ash hopper is located below the rear vertical shaft, and the rear vertical shaft and the flue ash hopper are flexibly connected by the non-metallic expansion joint. The two support leg assemblies are located at the bottom of the flue ash hopper. Each support leg assembly includes several legs arranged sequentially along a second direction. The two ash hopper support trusses are respectively fitted below the two support leg assemblies. Several supports are provided on the top of the ash hopper support trusses along the second direction. The support legs are movably fitted onto corresponding supports. The supports provide movable support for the support legs and limit their movement to prevent them from falling out of the supports. This utility model fundamentally solves the risk of the flue ash hopper falling from the rear vertical shaft due to weld cracking, reduces the difficulty of selecting wall-mounted pipes, and ensures the safety and stability of boiler operation. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the structure of this utility model;
[0018] Figure 2 This is a utility model Figure 1 Schematic diagram of the structure at point A;
[0019] Figure 3 This is a partial structural schematic diagram of the present invention. Figure 1 ;
[0020] Figure 4 This is a partial structural schematic diagram of the present invention. Figure 2 ;
[0021] Figure 5 This is a structural schematic diagram of the ash hopper support truss of this utility model;
[0022] In the attached diagram: 1. Rear shaft; 2. Flue ash hopper; 3. Non-metallic expansion joint; 4. Ash hopper support truss; 5. Support leg; 6. Support; 7. First limiting component; 8. Second limiting component; 51. Connecting chassis; 52. Sliding block; 61. Supporting top plate. Detailed Implementation
[0023] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but the present invention is not limited to the following embodiments.
[0024] Example 1:
[0025] See attached Figure 1 Appendix Figure 4A Π-shaped boiler with a split flue includes a rear vertical shaft 1, a flue ash hopper 2, a non-metallic expansion joint 3, two support leg assemblies, and two ash hopper support trusses 4. The flue ash hopper 2 is located below the rear vertical shaft 1, and the rear vertical shaft 1 and the flue ash hopper 2 are flexibly connected by the non-metallic expansion joint 3. The two support leg assemblies are located at the bottom of the flue ash hopper 2 and are arranged opposite each other along a first direction. Each support leg assembly includes several support legs 5 arranged sequentially along a second direction. The two ash hopper support trusses 4 extend along the second direction and are respectively equipped with... The ash hopper support truss 4 is located below the two support leg groups; the top of the ash hopper support truss 4 is provided with several supports 6 along the second direction, and each support 6 corresponds to one support leg 5 in the corresponding support leg group; the support leg 5 is movably fitted onto the corresponding support 6; the support 6 is used to provide movable support for the support leg 5 and to limit its movement, preventing the support leg 5 from falling out of the support 6; the length direction of the rear shaft 1 is the third direction, and both the first direction and the second direction are perpendicular to the third direction, and the first direction and the second direction are perpendicular to each other. From the above structure, it can be seen that in the boiler, flue gas flows through the rear shaft 1 into the flue ash hopper 2, and then the flue ash is stored in the flue ash hopper 2. In this invention, the rear shaft 1 and the flue ash hopper 2 are not connected by a traditional welded integrated connection. Instead, the flue ash hopper 2 is designed as a separate unit, using a non-metallic expansion joint 3 to flexibly connect them. When the rear shaft 1 and the flue ash hopper 2 expand due to heat during boiler operation, the non-metallic expansion joint 3 has a certain elastic deformation capacity to compensate for the deformation of the rear shaft 1 and the flue ash hopper 2. By changing the connection method, the hidden danger of the flue ash hopper 2 falling off due to weld cracking is fundamentally eliminated, and the misalignment or loosening of the additional protective plate due to deformation is also avoided. In order to prevent the flue ash hopper 2 from transferring the load to the rear shaft 1 and causing the rear shaft 1 to be overloaded, an ash hopper support truss 4 is designed. Two ash hopper support trusses 4 are fixed below the rear shaft 1 to provide independent support for the flue ash hopper 2, bearing the load of the flue ash hopper 2. This greatly reduces the burden on the rear shaft 1, thereby reducing the load required for the wall-mounted pipes installed on the rear shaft 1, simplifying the selection of wall-mounted pipes, and enabling more types of wall-mounted pipes to meet the safe operation requirements of the boiler. Two support leg groups are arranged opposite each other at the bottom of the flue ash hopper 2 along a first direction. Each support leg group includes several support legs 5. The two support leg groups are parallel to each other, and the support legs 5 of one support leg group are symmetrically arranged with the corresponding support legs 5 of the other support leg group along the first direction, and their positions correspond. In this invention, the length direction of the rear shaft 1 is defined as the third direction. Both the first direction and the second direction are perpendicular to the third direction, and the first direction and the second direction are perpendicular to each other. Specifically, the first direction is the horizontal direction in the attached drawing, i.e., the X-axis direction; the second direction is the front-back direction in the attached drawing, i.e., the Z-axis direction; and the third direction is the vertical direction in the attached drawing, i.e., the Y-axis direction.Two ash hopper support trusses 4 extend along the second direction and are respectively positioned below the two leg assemblies, providing movable support for the corresponding leg assemblies. Each support 6 corresponds to one leg 5 in the corresponding leg assembly, and each leg 5 is movably mounted on a corresponding support 6. When the flue ash hopper 2 expands due to heat, the leg 5 will also slide on the corresponding support 6. While providing support for the leg 5, the support 6 also confines the flue ash hopper 2 within its range, ensuring that the flue ash hopper 2 is always supported by the two ash hopper support trusses 4 during boiler operation. This utility model fundamentally eliminates the hidden danger of the flue ash hopper 2 falling off due to weld cracking caused by thermal or mechanical stress by changing the connection method between the flue ash hopper 2 and the rear vertical shaft 1. By supporting and limiting the support legs 5 through the support 6, it can provide support force for the flue ash hopper 2 to reduce the load on the rear vertical shaft 1, while limiting the expansion and slippage of the flue ash hopper 2. The support effect is good and ensures the safety of boiler operation.
[0026] Example 2:
[0027] See attached Figures 1-5 Based on Embodiment 1, the support 6 is provided with a supporting top plate 61 at its top; the support leg 5 includes a connecting base 51 and a slider 52; the connecting base 51 is located at the bottom of the support leg 5; the top of the slider 52 is connected to the center of the bottom surface of the connecting base 51; the slider 52 has a contact bottom surface for sliding contact with the top surface of the supporting top plate 61; the support 6 is also provided with a limiting component, which is used to limit the displacement range of the support leg 5 on the supporting top plate 61 along a first direction and / or a second direction. As can be seen from the above structure, the support leg 5 is provided with a connecting base 51 at its bottom, and the center of the bottom surface of the connecting base 51 is connected to the top of the slider 52. When the support leg 5 moves, the contact bottom surface of the slider 52 will contact and slide with the top surface of the supporting top plate 61. Specifically, the top surface of the supporting top plate 61 is a horizontal plane. When the flue ash hopper 2 is heated and expands, it will drive the slider 52 to move in a direction perpendicular to the Y-axis, thereby driving the connecting base 51 to move synchronously. Therefore, by setting a limiting component, the displacement range of the outrigger 5 when sliding on the support plate 61 along the first direction and / or the second direction is limited, preventing the outrigger 5 from falling out of the support 6.
[0028] The contact bottom surface of the slider 52 is a downwardly convex arc surface. As can be seen from the above structure, the downwardly convex arc surface of the contact bottom surface of the slider 52 avoids excessive friction between the contact bottom surface and the supporting top plate 61, preventing jamming and ensuring smoother expansion and sliding of the flue ash hopper. Specifically, the materials, dimensions, and curvature of the contact bottom surfaces of the slider 52 and the supporting top plate 61 can be adaptively set according to actual usage requirements.
[0029] The limiting assembly includes several first limiting members 7; these first limiting members 7 are arranged opposite each other on both sides of the top surface of the supporting top plate 61 along a second direction, providing limiting in the second and third directions for the connecting chassis 51. As can be seen from the above structure, the several first limiting members 7 are arranged opposite each other on both sides of the top surface of the supporting top plate 61 along a second direction, providing limiting in the second and third directions for the connecting chassis 51. When the connecting chassis 51 is fitted within the several first limiting members 7, there is a certain movable gap between the connecting chassis 51 and any one of the first limiting members 7, allowing the connecting chassis 51 to move to a certain extent relative to the surrounding first limiting members 7 in the second and third directions when the outrigger 5 is displaced.
[0030] The first limiting member 7 is an inverted L-shaped limiting block; the inverted L-shaped limiting block includes a first side and a second side; the first side is disposed on the top surface of the supporting top plate 61 and extends along a third direction; one end of the second side is connected to the top of the first side, and the other end extends along a second direction towards the side closer to the connecting chassis 51. As can be seen from the above structure, the first limiting member 7 is an inverted L-shaped limiting block, including a first side and a second side. The first side is disposed above the top surface of the supporting top plate 61 and extends along a third direction, used to contact the top surface of the connecting chassis 51 and restrict the displacement of the connecting chassis 51 in the third direction. One end of the second side is connected to the top of the first side, and the other end extends along a second direction towards the side closer to the connecting chassis 51, used to contact the side wall of the connecting chassis 51 and restrict the displacement of the connecting chassis 51 in the second direction, ensuring the limiting effect.
[0031] The number of the first limiting member 7 can be adapted to actual needs. Preferably, there are four first limiting members 7, which are symmetrically arranged in pairs on the supporting top plate 61 along the second direction.
[0032] Example 3:
[0033] See attached Figures 1-5 Based on Embodiment 2, the limiting component further includes several second limiting members 8; these second limiting members 8 are arranged opposite to each other on both sides of the top surface of the supporting top plate 61 along a first direction, and the height of the top surface of the second limiting member 8 is lower than the height of the bottom surface of the connecting chassis 51; the second limiting members 8 are used to limit the displacement of the slider 52 on the supporting top plate 61 in the first direction. As can be seen from the above structure, the second limiting members 8 are used to limit the slider 52. The several second limiting members 8 are arranged opposite to each other on both sides of the top surface of the supporting top plate 61 along a first direction, and the height of the top surface of the second limiting member 8 is lower than the height of the bottom surface of the connecting chassis 51, preventing friction and collision between the second limiting members 8 and the connecting chassis 51. The second limiting members 8 can limit the displacement of the slider 52 on the supporting top plate 61 in the first direction, further ensuring the limiting effect on the support leg 5. Specifically, the second limiting member 8 can be a rectangular limiting block.
[0034] The outlet diameter of the rear shaft 1 is the same as the inlet diameter of the flue ash hopper 2. As can be seen from the above structure, setting the outlet diameter of the rear shaft 1 and the inlet diameter of the flue ash hopper 2 to be the same facilitates the selection and connection arrangement of the non-metallic expansion joint 3.
[0035] The ash hopper support truss 4 is a steel truss made of Q355B steel. As can be seen from the above structure, the steel truss made of Q355B steel has good fatigue resistance, corrosion resistance, and shear resistance, which can meet the support requirements of the flue ash hopper 2 under different load conditions. Preferably, the ash hopper support truss 4 can also be made of other low-alloy steel.
[0036] Furthermore, in the definition of direction used by those skilled in the art of power plant boilers, the X-axis direction is the front-back direction of the field, the Y-axis direction is the up-down direction of the field, and the Z-axis direction is the left-right direction of the field. However, the directions described in this specification are based on the directions in the attached drawings.
[0037] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural or procedural transformations made based on the content of the present utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present utility model.
Claims
1. A Π-type boiler with a split flue, characterized in that: The system includes a rear shaft (1), a flue ash hopper (2), a non-metallic expansion joint (3), two support leg assemblies, and two ash hopper support trusses (4). The flue ash hopper (2) is located below the rear shaft (1), and the rear shaft (1) and the flue ash hopper (2) are flexibly connected by the non-metallic expansion joint (3). The two support leg assemblies are located at the bottom of the flue ash hopper (2) and are arranged opposite each other along a first direction. The support leg assembly includes several support legs (5) arranged sequentially along a second direction. The two ash hopper support trusses (4) extend along the second direction and are respectively matched with the two support legs. Below the group; the top of the ash hopper support truss (4) is provided with several supports (6) along the second direction, and each support (6) corresponds to one leg (5) in the corresponding leg group; the leg (5) is movably fitted on the corresponding support (6); the support (6) is used to provide movable support for the leg (5) and limit its movement to prevent the leg (5) from falling out of the support (6); the length direction of the rear shaft (1) is the third direction, and both the first direction and the second direction are perpendicular to the third direction, and the first direction and the second direction are perpendicular to each other.
2. The Π-type boiler with a split flue as described in claim 1, characterized in that: The support (6) is provided with a support plate (61) at the top; the support leg (5) includes a connecting base (51) and a slider (52); the connecting base (51) is located at the bottom of the support leg (5); the top of the slider (52) is connected to the center of the bottom surface of the connecting base (51); the slider (52) has a contact bottom surface for sliding contact with the top surface of the support plate (61); the support (6) is also provided with a limiting component, which is used to limit the displacement range of the support leg (5) on the support plate (61) along the first direction and / or the second direction.
3. The Π-type boiler with a split flue as described in claim 2, characterized in that: The contact bottom surface of the slider (52) is a downwardly convex arc surface.
4. The Π-type boiler with a split flue as described in claim 2, characterized in that: The limiting component includes several first limiting members (7); the several first limiting members (7) are disposed opposite to each other on both sides of the top surface of the supporting top plate (61) along the second direction, for providing limiting in the second direction and third direction for connecting the chassis (51).
5. The Π-type boiler with a split flue as described in claim 4, characterized in that: The first limiting member (7) is an inverted L-shaped limiting block; the inverted L-shaped limiting block includes a first side and a second side; the first side is located on the top surface of the supporting top plate (61) and extends along a third direction; one end of the second side is connected to the top of the first side, and the other end extends along a second direction toward the side close to the connecting chassis (51).
6. The Π-type boiler with a split flue according to claim 4 or 5, characterized in that: The limiting component also includes a plurality of second limiting members (8); the plurality of second limiting members (8) are disposed opposite to each other on both sides of the top surface of the supporting top plate (61) along the first direction, and the height of the top surface of the second limiting member (8) is lower than the height of the bottom surface of the connecting chassis (51); the second limiting member (8) is used to limit the displacement of the slider (52) on the supporting top plate (61) in the first direction.
7. The Π-type boiler with a split flue as described in claim 1, characterized in that: The outlet diameter of the rear shaft (1) is the same as the inlet diameter of the flue ash hopper (2).
8. The Π-type boiler with a split flue as described in claim 1, characterized in that: The ash hopper support truss (4) is a steel truss made of Q355B steel.