Water plate type heat exchanger guiding device arranged in boiler outlet flue

Abstract

The invention provides a water plate type heat exchanger guiding device arranged in a boiler outlet flue, and belongs to the field of industrial boiler transformation. The problem of fixing failure of the water plate type heat exchanger caused by conflict between metal thermal expansion in a high-temperature flue gas environment and a traditional welding type guide structure is solved. The device comprises a guide steel plate, a guide rod, a pin and a lug plate, the lug plates comprise the first lug plate welded to the side face of the boiler steel column and the second lug plate welded to the side face of the chimney, and the first lug plate and the second lug plate are each provided with a through hole. The pins comprise a first pin connected with the guide steel plate and a second pin connected with the guide rod; the guide steel plate is arranged at the front end of the water plate type heat exchanger in the smoke flowing direction and connected with a first lug plate on a boiler steel column through a first pin. The guide rod is arranged at the rear end of the water plate type heat exchanger in the smoke flowing direction and connected with a second lug plate on the chimney through a second pin. The fixing device is mainly used for fixing the water plate type heat exchanger.

Description

Technical Field

[0001] The invention belongs to the technical field of industrial boiler transformation, and in particular relates to a water plate heat exchanger guide device arranged in a boiler outlet flue. Background Art

[0002] In waste heat boiler systems, to improve energy efficiency, a water-plate heat exchanger is often added to the boiler outlet flue to recover waste heat from the flue gas. However, the installation of a water-plate heat exchanger brings the risk of structural instability. High-temperature flue gas will cause significant thermal expansion of the metal water-plate heat exchanger and its supporting structures. The continuous horizontal thrust generated by the flue gas flow and the multi-directional horizontal forces caused by sudden loads such as earthquakes need to be dissipated through reliable force transmission paths to ensure the safe operation of the equipment.

[0003] Traditional guide devices usually use welding or rigid connection methods, but there are obvious limitations in the application scenarios of waste heat boiler systems. If the water-plate heat exchanger or its attached guide components in a high-temperature environment are directly welded to the boiler steel column or chimney at room temperature, the huge temperature difference will induce thermal stress, which can easily lead to weld cracking or connection failure in the long term. At the same time, rigid constraints will hinder the natural expansion of the water-plate heat exchanger after heating, resulting in excessive internal stress, which can cause equipment deformation or damage. In addition, the internal space of the flue is limited and needs to be fixed on the existing structure, making it difficult to adopt the solution of adding a large support frame. Summary of the Invention

[0004] In view of this, the present invention aims to propose a water-plate heat exchanger guide device arranged in the boiler outlet flue to solve the problem of water-plate heat exchanger fixation failure caused by the conflict between metal thermal expansion and traditional welded guide structure in high-temperature flue gas environment.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a guide device for a water-plate heat exchanger disposed in a boiler outlet flue. The water-plate heat exchanger is located in the flue between a boiler steel column and a chimney. The outer surface of a flue plate of a flue sidewall is connected to the boiler steel column. The guide device comprises a guide steel plate, a guide rod, a pin, and a lug plate. The lug plate comprises a first lug plate welded to the side of the boiler steel column and a second lug plate welded to the side of the chimney. Both the first and second lug plates are provided with through holes. The pins comprise a first pin connected to the guide steel plate and a second pin connected to the guide rod. The guide steel plate is disposed at the front end of the water-plate heat exchanger in the direction of flue gas flow and is connected to the first lug plate on the boiler steel column via the first pin. The guide rod is disposed at the rear end of the water-plate heat exchanger in the direction of flue gas flow and is connected to the second lug plate on the chimney via the second pin. An axial expansion gap is formed between the inner wall of the through hole in the lug plate and the outer wall of the corresponding pin. The size of the axial expansion gap is greater than the axial displacement of the water-plate heat exchanger due to thermal expansion. Furthermore, the number of the guide steel plates is determined according to the horizontal tension generated by the smoke flow and the rated tension value of a single guide steel plate.

[0006] Furthermore, the number of the guide rods is the same as the number of the guide steel plates, and the guide rods and the guide steel plates are symmetrically arranged along the water-plate heat exchanger.

[0007] Furthermore, there are multiple first ear plates, and the multiple first ear plates are welded to the side surface of the boiler steel column at equal intervals.

[0008] Furthermore, there are multiple second ear plates, and the multiple second ear plates are welded to the side of the chimney at equal intervals.

[0009] Furthermore, the guide steel plate and the guide rod are both made of high-temperature resistant steel.

[0010] Furthermore, the first ear plate is welded to the side surface of the boiler steel column near the connection with the flue plate.

[0011] Furthermore, the second ear plate is welded to the side surface of the chimney close to the flue plate.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. The guide device of the present application solves the problems of thermal expansion constraint and horizontal force transmission of the water-plate heat exchanger in a high-temperature flue environment through a specific structural design. The guide steel plate and the guide rod are respectively connected to the boiler steel column and the ear plate welded on the chimney through pins. The axial expansion gap set between the through hole on the ear plate and the pin is larger than the thermal expansion displacement of the heat exchanger, so that the heat exchanger can freely expand and contract along the axial direction under the action of high-temperature flue gas, completely avoiding the accumulation of metal thermal stress caused by temperature difference in traditional welding connections, preventing weld cracking or equipment deformation and failure, and several ear plates are welded at equal intervals on the boiler steel column and the side of the chimney near the flue plate connection, directly utilizing the existing structure for load-bearing, without destroying the original flue or adding a support frame.

[0013] 2. The guide steel plates of this application are arranged at the front end of the flue gas flow direction of the heat exchanger. The number of guide steel plates is determined according to the horizontal tension of the flue gas and the rated bearing capacity of a single steel plate. When the flue gas generates a thrust from the front of the furnace to the back of the furnace, the guide steel plates are pulled and the horizontal force is transferred to the boiler steel column, effectively limiting the backward displacement of the heat exchanger.

[0014] 3. The guide rods and guide steel plates in this application are the same in number and are symmetrically arranged at the rear end of the heat exchanger. When an earthquake occurs, the horizontal force from the rear of the furnace to the front of the furnace is transmitted to the chimney by the guide rods, and the left and right forces are constrained by the flue plate itself. The guide steel plates and guide rods work together to form a two-way horizontal force transmission path to ensure the overall stability of the equipment under sudden loads.

[0015] 4. The guide steel plate and guide rod of this application are made of high-temperature resistant steel to avoid degradation of material properties caused by high-temperature flue gas. While achieving reliable transmission of horizontal force and release of thermal expansion, this structure takes into account adaptability to high-temperature environments and convenience of on-site installation and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which constitute part of the present invention, are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings: Figure 1 This is a front structural schematic diagram of the installation of a water plate heat exchanger guide device arranged in a boiler outlet flue according to the present invention; Figure 2 This is a schematic diagram of the top structure of the installation of a water-plate heat exchanger guide device arranged in a boiler outlet flue according to the present invention.

[0017] In the picture: 1. Chimney; 2. Guide rod; 3. Guide steel plate; 4. Boiler steel column; 5. First pin; 6. Second pin; 7. Water-plate heat exchanger; 8. Flue plate; 9. First ear plate; 10. Second ear plate. DETAILED DESCRIPTION

[0018] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely explain the technical solutions in the embodiments of the present invention. It should be noted that the embodiments of the present invention and the features therein can be combined with each other in the absence of conflict, and the embodiments described are only part of the embodiments of the present invention, not all of the embodiments.

[0019] Specific implementation method: see Figure 1-2This embodiment describes a water-plate heat exchanger guide device disposed in a boiler outlet flue. The water-plate heat exchanger 7 is located in the flue between the boiler steel column 4 and the chimney 1. The outer surface of the flue plate 8 on the flue sidewall is connected to the boiler steel column 4. The flue plate 8 includes a guide steel plate 3, a guide rod 2, a pin, and a lug plate. The lug plate includes a first lug plate 9 welded to the side of the boiler steel column 4 and a second lug plate 10 welded to the side of the chimney 1. The first lug plate 9 and the second lug plate 10 are both provided with through holes. The lug plates provide fixed fulcrums for the pins. The hydraulic force is dispersed and transmitted to the boiler steel column 4 and the chimney 1; the pins include a first pin 5 connected to the guide steel plate 3 and a second pin 6 connected to the guide rod 2. The pins replace traditional welding to avoid the thermal stress caused by direct welding of the water plate heat exchanger 7 to the boiler steel column 4 and the chimney 1; the guide steel plate 3 is set at the front end of the water plate heat exchanger 7 along the flue gas flow direction, and is connected to the first ear plate 9 on the boiler steel column 4 through the first pin 5. When a horizontal force is generated in the direction from the front of the furnace to the back of the furnace, the guide steel plate 3 is subjected to tension and the thrust is transmitted To the boiler steel column 4, prevent the water plate heat exchanger 7 from moving backward, the guide steel plate 3 constrains the water plate heat exchanger 7 to move backward under the action of horizontal force through the connection of the first pin 5, thereby maintaining the stability of the position of the water plate heat exchanger 7; the guide rod 2 is set at the rear end of the water plate heat exchanger 7 along the flue gas flow direction, and is connected to the second ear plate 10 on the chimney 1 through the second pin 6. When a horizontal pulling force is generated in the direction from the rear of the furnace to the front of the furnace, the guide rod 2 is subjected to the pulling force and the pulling force is transmitted to the chimney 1, preventing the water plate heat exchanger 7 from moving forward, and the guide rod The connection of the second pin 6 constrains the water-plate heat exchanger 7 from moving forward under the action of horizontal tension, thereby maintaining the stability of the position of the water-plate heat exchanger 7. An axial expansion gap is formed between the inner wall of the through hole on the ear plate and the outer wall of the corresponding pin, and the size of the axial expansion gap is greater than the axial displacement of the water-plate heat exchanger 7 due to thermal expansion, thereby allowing the water-plate heat exchanger 7 to expand and contract freely at high temperatures, eliminating the risk of deformation or cracking caused by thermal stress, and maintaining the connection between the pin and the ear plate during the expansion process, ensuring uninterrupted transmission of horizontal force.

[0020] The working principle of the present invention is as follows: The guide device of the present invention realizes the stable operation of the water-plate heat exchanger 7 in a high-temperature flue environment through a specific structure. When the boiler is running, the high-temperature flue gas flows through the water-plate heat exchanger 7, causing its metal structure to expand due to heat. At this time, the axial expansion gap between the through hole on the ear plate and the outer wall of the pin provides a freely retractable workpiece for the water-plate heat exchanger. The size of the expansion gap is larger than the axial displacement of the water-plate heat exchanger 7 due to thermal expansion, thereby completely releasing thermal stress and avoiding equipment deformation or weld cracking; when the flue gas flow generates a horizontal thrust from the front of the furnace to the back of the furnace, the guide steel plate 3 arranged at the front end of the water-plate heat exchanger 7 is subjected to tension, and the tension is transmitted to the first ear plate 9 welded to the side of the boiler steel column 4 through the first pin 5. Finally, the boiler steel column 4 bears the load. At this time, the guide steel plate 3 constrains the water-plate heat exchanger The water-plate heat exchanger 7 moves backward to maintain the stability of the position of the water-plate heat exchanger 7; when sudden loads such as earthquakes generate horizontal force from the rear of the furnace to the front of the furnace, the guide rod 2 arranged at the rear of the water-plate heat exchanger 7 is subjected to tension, and the tension is transmitted to the second ear plate 10 welded to the side of the chimney 1 through the second pin 6. The chimney 1 realizes the load-bearing, and the guide rod 2 constrains the water-plate heat exchanger 7 to move forward; the horizontal force in the left and right directions of the water-plate heat exchanger 7 is limited by the structure of the flue plate 8. The guide steel plate 3 and the guide rod 2 form a two-way force transmission path to ensure the reliable dissipation of the horizontal force under different working conditions. During the whole process, the pin connection replaces the traditional welding structure, and the expansion gap function is always maintained while transmitting the horizontal force, so that the water-plate heat exchanger 7 reaches a dynamic balance between thermal expansion and mechanical constraint, ensuring the long-term safe operation of the equipment.

[0021] The number of the guide steel plates 3 is determined based on the horizontal tension generated by the flue gas flow and the rated tension value of a single guide steel plate 3, that is, the total bearing capacity of all guide steel plates 3 needs to be greater than the maximum horizontal tension generated by the flue gas. The rated tension of a single guide steel plate 3 is determined by the material and cross-sectional dimensions of the guide steel plate 3, and can be determined through conventional mechanical calculations or implementations.

[0022] The number of the guide rods 2 is the same as the number of the guide steel plates 3, and the guide rods 2 and the guide steel plates 3 are symmetrically arranged along the water-plate heat exchanger 7. The number of the guide rods 2 is the same as the number of the guide steel plates 3 to ensure that the maximum bearing capacity in the direction from the rear of the furnace to the front of the furnace is consistent with that in the direction from the front of the furnace to the rear of the furnace, avoiding weak unidirectional force transmission capacity. The symmetrical arrangement makes the guide rods 2 and the guide steel plates 3 radially distributed along the axis of the water-plate heat exchanger 7, ensuring that the points of application of the horizontal force are symmetrical. If they are not symmetrical, the horizontal force will generate additional torque, causing the water-plate heat exchanger 7 to twist or the ear plate to be locally overloaded.

[0023] There are multiple first ear plates 9, and multiple first ear plates 9 are welded at equal intervals on the side of the boiler steel column 4. The horizontal tension of the flue gas transmitted by the guide steel plate 3 is finally dispersed to the boiler steel column 4 through the first ear plate 9. If only a single first ear plate 9 is set, the concentrated load will easily cause the ear plate weld or the local stress of the boiler steel column 4 to exceed the limit. The equal-interval distribution ensures that the multiple first ear plates 9 are subjected to balanced force.

[0024] There are multiple second ear plates 10, and the multiple second ear plates 10 are welded on the side of the chimney 1 at equal intervals. The horizontal force from the rear of the furnace to the front of the furnace transmitted by the guide rod 2 needs to be dispersed to the chimney 1 through the second ear plates 10. The multiple second ear plates 10 are arranged in parallel to evenly distribute the total tension to the bearing surface of the chimney 1, reducing single-point stress. The equal-interval arrangement makes the second ear plates 10 evenly stressed, avoiding overload of some second ear plates 10 due to uneven spacing.

[0025] The guide steel plate 3 and the guide rod 2 are both made of high temperature resistant steel. The high temperature resistant steel can be made of steel plates for boiler pressure vessels or heat resistant alloy structural steel.

[0026] The first ear plate 9 is welded to the side of the boiler steel column 4 near the connection with the flue plate 8. The connection node between the flue plate 8 and the boiler steel column 4 is the area with the strongest rigidity in the flue system. There is a local reinforcement effect here due to the welding of the flue plate 8. By welding the first ear plate 9 at this position, the ultra-high rigidity of this area can be directly used to transmit horizontal force, thereby avoiding deformation of the non-node area of the boiler steel column 4 due to insufficient load-bearing.

[0027] The second ear plate 10 is welded to the side of the chimney 1 close to the flue plate 8. The reverse horizontal force transmitted by the guide rod 2 needs to be dispersed to the chimney 1 through the second ear plate 10. This force transmission path directly introduces the load into the rigid node area of the chimney 1, avoiding the long-distance transmission of force along the wall of the chimney 1 to generate additional bending moment.

[0028] The specific embodiments of the present invention disclosed above are intended only to help illustrate the present invention. The specific embodiments do not describe all details in detail, nor do they limit the invention to the specific embodiments described. Numerous modifications and variations are possible based on the contents of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention.

Claims

1. A water plate heat exchanger guide device arranged in a boiler outlet flue, wherein the water plate heat exchanger (7) is located in the flue between the boiler steel column (4) and the chimney (1), and the outer surface of the flue plate (8) of the flue side wall is connected to the boiler steel column (4), characterized in that: It comprises a guide steel plate (3), a guide rod (2), a pin and an ear plate; the ear plate comprises a first ear plate (9) welded to the side of the boiler steel column (4) and a second ear plate (10) welded to the side of the chimney (1), and the first ear plate (9) and the second ear plate (10) are both provided with through holes; the pin comprises a first pin (5) connected to the guide steel plate (3) and a second pin (6) connected to the guide rod (2); the guide steel plate (3) is provided on the water plate heat exchanger ( 7) along the front end of the flue gas flow direction and connected to the first ear plate (9) on the boiler steel column (4) through a first pin (5); the guide rod (2) is arranged at the rear end of the water plate heat exchanger (7) along the flue gas flow direction and connected to the second ear plate (10) on the chimney (1) through a second pin (6); an axial expansion gap is formed between the inner wall of the through hole on the ear plate and the outer wall of the corresponding pin, and the size of the axial expansion gap is greater than the axial displacement of the water plate heat exchanger (7) due to thermal expansion.

2. A water-plate heat exchanger guide device arranged in a boiler outlet flue according to claim 1, characterized in that: The number of the guide steel plates (3) is determined according to the horizontal tension generated by the flue gas flow and the rated tension value of a single guide steel plate (3).

3. The water-plate heat exchanger guide device provided in the boiler outlet flue according to claim 1, characterized in that: The number of the guide rods (2) is the same as the number of the guide steel plates (3), and the guide rods (2) and the guide steel plates (3) are symmetrically arranged along the water-plate heat exchanger (7).

4. The water-plate heat exchanger guide device provided in the boiler outlet flue according to claim 1, characterized in that: There are multiple first ear plates (9), and the multiple first ear plates (9) are welded to the side surface of the boiler steel column (4) at equal intervals.

5. The water-plate heat exchanger guide device provided in the boiler outlet flue according to claim 1, characterized in that: There are a plurality of second ear plates (10), and the plurality of second ear plates (10) are welded to the side surface of the chimney (1) at equal intervals.

6. The water-plate heat exchanger guide device provided in the boiler outlet flue according to claim 1, characterized in that: The guide steel plate (3) and the guide rod (2) are both made of high-temperature resistant steel.

7. The water-plate heat exchanger guide device provided in the boiler outlet flue according to claim 1, characterized in that: The first ear plate (9) is welded to the side surface of the boiler steel column (4) near the connection with the flue plate (8).

8. The water-plate heat exchanger guide device provided in a boiler outlet flue according to claim 1, characterized in that: The second ear plate (10) is welded to the side of the chimney (1) close to the flue plate (8).

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