Four-return-stroke flue structure of horizontal boiler
By designing a four-pass flue structure for the horizontal boiler, the problem of insufficient heat exchange in the flue of the existing membrane wall steam boiler was solved, realizing the full utilization of flue gas heat energy and improving the heat energy utilization rate.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-02
- Publication Date
- 2026-03-10
AI Technical Summary
The existing flue design of membrane wall steam boilers results in insufficient heat exchange in the outermost membrane wall, leading to the failure to fully utilize the heat from the flue gas and affecting the energy-saving effect of the steam boiler.
A four-pass flue structure for a horizontal boiler is designed. By setting multiple flues and flue holes between the shell and the membrane wall, a U-shaped flow channel with repeated rotation is formed, allowing the flue gas to flow repeatedly on both sides of the membrane wall to achieve full heat exchange.
It improves the utilization rate of flue gas heat energy, and enhances the efficiency of heat energy utilization through multiple heat exchanges.
Smart Images
Figure CN223985184U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of flue technology for membrane wall steam boilers, and particularly relates to a four-pass flue structure for a horizontal boiler. Background Technology
[0002] In existing membrane wall steam boilers, the flue structure causes the outermost membrane wall to always be in a situation of heat exchange on one side only. This means that the heat of the flue gas cannot be fully utilized, which is detrimental to the energy saving of the steam boiler. Therefore, how to fully improve the flue structure and make full use of the flow of flue gas to achieve full absorption of flue gas heat energy has become a problem that needs to be solved for membrane wall steam boilers. Summary of the Invention
[0003] The purpose of this utility model embodiment is to provide a four-pass flue structure for a horizontal boiler, which aims to solve the problem that the structure of the flue in existing membrane wall steam boilers causes the outermost membrane wall to always be in a single-sided heat exchange state.
[0004] The present invention is implemented as follows:
[0005] A four-pass flue structure for a horizontal boiler, comprising a shell and a membrane wall within the shell, the shell and membrane wall forming a first flue, a second flue, a third flue, and a fourth flue; the membrane wall forming the first and second flues of unequal size, and the shell and membrane wall forming the third and fourth flues of unequal size; the tail of the first flue and the head of the second flue are connected by a first smoke passage, the head of the first flue and the tail of the second flue are separated by a second flue baffle; the tail of the second flue is connected to the head of the third flue, the tail of the third flue is connected to the head of the fourth flue through the second smoke passage, the tail of the fourth flue is provided with a smoke outlet, and the head of the first flue is provided with a smoke inlet; the first flue baffle is fixed to the outside of the membrane wall and fixes the membrane wall and the shell together.
[0006] Furthermore, the first flue baffle is provided with two membrane walls, symmetrically arranged at the top and bottom.
[0007] Furthermore, the membrane wall includes a C-shaped first membrane wall, a V-shaped second membrane wall, and a C-shaped third membrane wall. The first and second membrane walls form a first flue, and the second and third membrane walls form a second flue. The volume of the first flue is greater than the volume of the second flue.
[0008] Furthermore, the length of the two ends of the first membrane wall of the C-shape is greater than the length of the two ends of the third membrane wall of the C-shape.
[0009] Furthermore, the first membrane wall, the second membrane wall, and the third membrane wall converge at one end to the lower manifold and at the other end to the upper manifold.
[0010] Furthermore, the ends of the first flue, second flue, third flue and fourth flue formed by the shell and membrane wall are sealed by end plates.
[0011] Furthermore, the end plate is divided into two parts, namely the first end plate and the second end plate.
[0012] Furthermore, the first end plate is located at the head of the four-pass flue and includes a first inner end wall, a first insulation layer is provided inside the first inner end wall, and a first outer end wall is provided outside the first insulation layer. The flue gas inlet is fixed to the side of the first outer end wall and passes through the first outer end wall, the first insulation layer and the first inner end wall, and communicates with the first flue. The second end plate is located at the tail of the four-pass flue and includes a second inner end wall, a second insulation layer is provided inside the second inner end wall, and a second outer end wall is provided outside the second insulation layer.
[0013] The positive effects of this utility model are as follows: the membrane wall forms a first flue and a second flue of different sizes, and the shell and the membrane wall form a third flue and a fourth flue of different sizes. The first flue partition is fixed to the outside of the membrane wall and the membrane wall and the shell are fixedly connected. The cavity formed by the shell and the membrane wall is divided into the third flue and the fourth flue of different sizes. At the same time, the tail of the third flue and the head of the fourth flue are connected by the second flue hole, forming a U-shaped four-pass flue with repeated rotating cross section. This allows the flue gas to flow repeatedly around both sides of the membrane wall, fully exchange heat, and improve the utilization rate of heat energy. Attached Figure Description
[0014] Figure 1 This is a front view of a four-pass flue structure of a horizontal boiler according to this utility model;
[0015] Figure 2 yes Figure 1 The figure shows a cross-sectional view along line AA of a four-pass flue structure of a horizontal boiler according to this utility model.
[0016] Figure 3 yes Figure 2 The figure shows a cross-sectional view along the BB direction of a four-pass flue structure of a horizontal boiler according to this utility model.
[0017] Figure 4 yes Figure 3 The figure shows a sectional view along the DD direction of a four-pass flue structure of a horizontal boiler according to this utility model.
[0018] Figure 5 yes Figure 3 The figure shows a cross-sectional view along the FF direction of a four-pass flue structure of a horizontal boiler according to this utility model.
[0019] Legend: 1—Lower manifold, 2—Shell, 201—First outer shell, 202—Second outer shell, 203—First insulation layer, 204—First outer end wall, 205—First inner end wall, 206—Second inner end wall, 3—Lower connector of water level gauge, 4—Upper connector of water level gauge, 5—Gas collection pipe, 6—External flange, 7—Upper manifold, 8—Smoke inlet, 9—Drain outlet, 10—Second outer end wall, 11—Second insulation layer, 12—Second smoke passage hole, 13—First flue baffle, 14—End plate, 15—Membrane wall, 1501—First membrane wall, 1502—Second membrane wall, 1503—Third membrane wall, 16—Fourth flue, 17—First flue, 18—Second flue, 19—Third flue, 20—Smoke outlet, 21—First smoke passage hole, 22—Second flue baffle. Detailed Implementation
[0020] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments:
[0021] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to 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 of this utility model.
[0022] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.
[0023] like Figures 1 to 5The diagram shown is a structural diagram of a four-pass flue structure for a horizontal boiler provided in an embodiment of this utility model. It includes a shell 2 and a membrane wall 15 within the shell. The shell 2 and the membrane wall 15 form a first flue 17, a second flue 18, a third flue 19, and a fourth flue 16. The membrane wall 15 forms the first flue 17 and the second flue 18, which are of different sizes. The shell 2 and the membrane wall 15 form the third flue 19 and the fourth flue 16, which are of different sizes. The diagram also includes the tail section of the first flue 17 and the second flue... The head of the first flue 17 passes through the first smoke passage 21. The head of the first flue 17 and the tail of the second flue 18 are separated by the second flue partition 22. The tail of the second flue 18 is connected to the head of the third flue 19. The tail of the third flue 19 is connected to the head of the fourth flue 16 through the second smoke passage 12. The tail of the fourth flue 16 is provided with a smoke outlet 20. The head of the first flue 17 is provided with a smoke inlet 8. The first flue partition 13 is fixed to the outside of the membrane wall and fixes the membrane wall and the shell together.
[0024] In this embodiment of the invention, the membrane wall 15 forms a first flue 17 and a second flue 18 of different sizes, and the shell 2 and the membrane wall 15 form a third flue 19 and a fourth flue 16 of different sizes. The first flue partition 13 is fixed to the outside of the membrane wall and the membrane wall and the shell are fixedly connected. The cavity formed by the shell 2 and the membrane wall 15 is divided into the third flue 19 and the fourth flue 16 of different sizes. At the same time, the tail of the third flue 19 and the head of the fourth flue 16 are connected by the second flue hole 12, forming a four-pass flue with a U-shaped cross-section formed by repeated rotation. This allows the flue gas to flow repeatedly around both sides of the membrane wall, fully exchange heat, and improve the utilization rate of heat energy.
[0025] Specifically:
[0026] A four-pass flue structure for a horizontal boiler includes a shell 2 and a membrane wall 15 inside the shell. The shell 2 and the membrane wall 15 form a first flue 17, a second flue 18, a third flue 19, and a fourth flue 16. The membrane wall 15 forms the first flue 17 and the second flue 18 of different sizes, and the shell 2 and the membrane wall 15 form the third flue 19 and the fourth flue 16 of different sizes. The tail of the first flue 17 and the head of the second flue 18 are connected by a first smoke passage 21. The head of the first flue 17 and the tail of the second flue 18 are separated by a second flue baffle 22. The tail of the second flue 18 is connected to the head of the third flue 19. The tail of the third flue 19 is connected to the head of the fourth flue 16 through a second smoke passage 12. The tail of the fourth flue 16 is provided with a smoke outlet 20. The head of the first flue 17 is provided with a smoke inlet 8. The first flue baffle 13 is fixed to the outside of the membrane wall and fixes the membrane wall and the shell together.
[0027] The first flue baffle 13 has two symmetrically arranged membrane walls 15 at the top and bottom. The first flue baffle 13 is welded to the inner side of the shell 2, and also to the upper manifold 7 or the lower manifold 1 of the membrane wall. The first flue baffle 13 is also welded to the inner side of the first inner end wall 205. The first flue baffle 13 maintains a certain distance from the second inner end wall, and this distance forms the first smoke passage 21. In this way, the first flue baffle 13 encloses the shell 2 and the membrane wall 15 into a cavity, which is divided into a first flue 17 and a second flue 18 connected by the first smoke passage 21.
[0028] The membrane wall 15 includes a C-shaped first membrane wall 1501, a V-shaped second membrane wall 1502, and a C-shaped third membrane wall 1503. The first membrane wall 1501 and the second membrane wall 1502 form a first flue, and the second membrane wall 1502 and the third membrane wall 1503 form a second flue. The volume of the first flue 17 is greater than the volume of the second flue 18.
[0029] The lengths of the two ends of the first membrane wall 1501 in the C-shape are greater than the lengths of the two ends of the third membrane wall 1503 in the C-shape.
[0030] The first membrane wall 1501, the second membrane wall 1502, and the third membrane wall 1503 converge at one end to the lower manifold 1 and at the other end to the upper manifold 7. The upper manifold 7 is connected to the gas collecting pipe 5, and the top of the gas collecting pipe 5 is provided with several external flanges 6 for connecting external equipment and instruments. The side of the gas collecting pipe 5 is provided with the upper connector 4 of the water level gauge, and the side of the upper manifold 7 is provided with the lower connector 3 of the water level gauge.
[0031] The first flue 17, the second flue 18, the third flue 19, and the fourth flue end 16, which are enclosed by the shell 2 and the membrane wall 15, are sealed by the end plate 14.
[0032] The end plate 14 is divided into two parts, namely the first end plate and the second end plate.
[0033] The first end plate is located at the head of the four-pass flue and includes a first inner end wall 205. A first insulation layer 203 is provided inside the first inner end wall, and a first outer end wall 204 is provided outside the first insulation layer 203. The flue gas inlet 8 is fixed to the side of the first outer end wall 204 and passes through the first outer end wall 204, the first insulation layer 203 and the first inner end wall 205, and communicates with the first flue 17. The second end plate is located at the tail of the four-pass flue and includes a second inner end wall 206. A second insulation layer 11 is provided inside the second inner end wall, and a second outer end wall 10 is provided outside the second insulation layer 11.
[0034] The foregoing has broadly outlined some aspects and features of the various embodiments and should be interpreted as merely illustrative of potential applications. Other beneficial results can be obtained by applying the disclosed information in different ways or by combining aspects of the disclosed embodiments. Further aspects and a more complete understanding can be obtained based on the detailed description of exemplary embodiments with reference to the accompanying drawings, within the scope defined by the claims.
[0035] The above embodiments provide a detailed description of the present invention. Of course, the above description is not intended to limit the present invention, nor is the present invention limited to the examples described above. Any changes, modifications, additions, reductions, or substitutions made by those skilled in the art within the scope of the present invention are also within the protection scope of the present invention.
Claims
1. A four-pass flue structure for a horizontal boiler, characterized by The four-pass flue comprises a shell and a membrane wall in the shell, the shell and the membrane wall enclose a first flue, a second flue, a third flue and a fourth flue, the membrane wall encloses the first flue and the second flue with different sizes, the shell and the membrane wall enclose the third flue and the fourth flue with different sizes; the tail of the first flue and the head of the second flue are connected through a first smoke hole, the head of the first flue and the tail of the second flue are separated by a first flue baffle, the tail of the second flue is communicated with the head of the third flue, the tail of the third flue is communicated with the head of the fourth flue through a second smoke hole, the tail of the fourth flue is provided with a smoke outlet, the head of the first flue is provided with a smoke inlet, and the first flue baffle is fixed outside the membrane wall and fixedly connected with the membrane wall and the shell.
2. A four pass flue structure for a horizontal boiler according to claim 1, characterized in that The first flue baffle is provided with two membrane walls symmetrically arranged at the top and bottom of the membrane wall.
3. A four pass flue structure for a horizontal boiler according to claim 2, wherein The membrane wall comprises a C-shaped first membrane wall, a V-shaped second membrane wall and a C-shaped third membrane wall, the first membrane wall and the second membrane wall enclose the first flue, and the second membrane wall and the third membrane wall enclose the second flue, and the volume of the first flue is greater than that of the second flue.
4. A four pass flue structure for a horizontal boiler according to claim 3, wherein The length of the two ends of the C-shaped first membrane wall is greater than that of the two ends of the C-shaped third membrane wall.
5. A four pass flue structure for a horizontal boiler according to claim 4, wherein The first membrane wall, the second membrane wall and the third membrane wall are gathered at a lower header at one end and an upper header at the other end.
6. A four-pass flue structure for a horizontal boiler according to any one of claims 1 to 5, characterized in that The shell and the membrane wall enclose the first flue, the second flue, the third flue and the fourth flue, and the ends are sealed by end plates.
7. A four pass flue structure for a horizontal boiler according to claim 6, characterized in that The end plates are divided into two parts, namely a first end plate and a second end plate.
8. A four pass flue structure for a horizontal boiler according to claim 7, characterized in that The first end plate is located at the head of the four-pass flue and comprises a first inner end wall, a first heat preservation layer is arranged in the first inner end wall, a first outer end wall is arranged outside the first heat preservation layer, the smoke inlet is fixed on the side edge of the first outer end wall and penetrates through the first outer end wall, the first heat preservation layer and the first inner end wall, and is communicated with the first flue; the second end plate is located at the tail of the four-pass flue and comprises a second inner end wall, the second inner end wall is provided with a second heat preservation layer, and the second outer end wall is arranged outside the second heat preservation layer.