A water plate heat exchanger guide device arranged in a boiler outlet flue

Abstract

The application provides a water plate type heat exchanger guide device arranged in a boiler outlet flue, and belongs to the field of industrial boiler modification. The water plate type heat exchanger guide device solves the problem of water plate type heat exchanger fixing failure caused by the conflict between metal thermal expansion and traditional welding type guide structure under a high-temperature flue gas environment. The water plate type heat exchanger guide device comprises a guide steel plate, a guide rod, a pin and an ear plate. The ear plate comprises a first ear plate welded to the side of a boiler steel column and a second ear plate welded to the side of a chimney. The first ear plate and the second ear plate are both provided with penetrating holes. The pin comprises 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 along the flue gas flow direction and is connected with the first ear plate on the boiler steel column through the first pin. The guide rod is arranged at the rear end of the water plate type heat exchanger along the flue gas flow direction and is connected with the second ear plate on the chimney through the second pin. The water plate type heat exchanger guide device is mainly used for fixing the position of the water plate type heat exchanger.

Description

Technical Field

[0001] This invention belongs to the field of industrial boiler retrofitting technology, and in particular relates to a water plate heat exchanger guide device installed in the boiler outlet flue. Background Technology

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

[0003] Traditional guiding devices typically employ welding or rigid connections, but these methods have significant limitations in the application scenarios of waste heat boiler systems. If a water-plate heat exchanger or its associated guiding components, which are located in a high-temperature environment, are directly welded to a boiler steel column or chimney at room temperature, the huge temperature difference will induce thermal stress. Over time, this can easily lead to weld cracking or connection failure. At the same time, rigid constraints will hinder the natural expansion of the water-plate heat exchanger after heating, generating excessive internal stress, which can cause equipment deformation or damage. Furthermore, the internal space of the flue is limited and needs to be fixed to the existing structure, making it difficult to adopt a solution that adds a large supporting frame. Summary of the Invention

[0004] In view of this, the present invention aims to propose a guide device for a water-plate heat exchanger installed in the boiler outlet flue, so as to solve the problem of water-plate heat exchanger fixation failure caused by the conflict between metal thermal expansion and traditional welded guide structure under 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 installed in the boiler outlet flue, wherein the water-plate heat exchanger is located in the flue between the boiler steel column and the chimney, and the outer surface of the flue plate on the sidewall of the flue is connected to the boiler steel column. It includes a guide steel plate, a guide rod, a pin, and ear plates; the ear plates include a first ear plate welded to the side of the boiler steel column and a second ear plate welded to the side of the chimney, both having through holes; the pins include a first pin connected to the guide steel plate and a second pin connected to the guide rod; the guide steel plate is located at the front end of the water-plate heat exchanger along the flue gas flow direction and is connected to the first ear plate on the boiler steel column via the first pin; the guide rod is located at the rear end of the water-plate heat exchanger along the flue gas flow direction and is connected to the second ear plate on the chimney via the second pin; 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 due to thermal expansion.

[0006] Furthermore, the number of guide steel plates is determined based on the horizontal tension generated by the flue gas flow and the rated tension value of a single guide steel plate.

[0007] Furthermore, the number of guide rods is the same as the number of guide steel plates, and the guide rods and guide steel plates are arranged symmetrically along the water plate heat exchanger.

[0008] Furthermore, there are multiple first ear plates, which are welded at equal intervals to the side of the boiler steel column.

[0009] Furthermore, there are multiple second ear plates, which are welded at equal intervals to the side of the chimney.

[0010] Furthermore, both the guide plate and the guide rod are made of high-temperature resistant steel.

[0011] Furthermore, the first ear plate is welded to the side of the boiler steel column near the flue plate.

[0012] Furthermore, the second ear plate is welded to the side of the chimney near the flue plate.

[0013] Compared with the prior art, the beneficial effects of the present invention are:

[0014] 1. The guiding device of this application solves the problem of thermal expansion constraint and horizontal force transmission of water plate heat exchangers in high-temperature flue environments through a specific structural design. The guide steel plate and guide rod are respectively connected to the ear plates welded on the boiler steel column and the chimney by pins. The axial expansion gap 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 axis under the action of high-temperature flue gas. This completely avoids the accumulation of metal thermal stress caused by temperature difference in traditional welded connections, prevents weld cracking or equipment deformation failure, and several ear plates are welded at equal intervals on the side of the boiler steel column and the chimney near the connection of the flue plate, directly utilizing the existing structure for load bearing, without damaging the original flue or adding a support frame.

[0015] 2. The guide steel plates of this application are set at the front end of the flue gas flow direction of the heat exchanger. Their number 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 to the rear of the furnace, the guide steel plates are stretched and transmit the horizontal force to the boiler steel column, effectively restricting the heat exchanger from moving backward.

[0016] 3. The number of guide rods and guide steel plates in this application are the same and they 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.

[0017] 4. The guide steel plate and guide rod of this application are made of high temperature resistant steel to avoid material performance degradation caused by high temperature flue gas. This structure can reliably transmit horizontal force and release thermal expansion while taking into account high temperature environment adaptability and on-site installation and maintenance convenience. Attached Figure Description

[0018] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0019] Figure 1 This is a front view of the installation of a water plate heat exchanger guide device installed in the boiler outlet flue, as described in this invention.

[0020] Figure 2 This is a top-view structural diagram of the guide device for a water plate heat exchanger installed in the boiler outlet flue, as described in this invention.

[0021] In the picture:

[0022] 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 Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other, and the described embodiments are only some embodiments of the present invention, not all embodiments.

[0024] Detailed implementation method: See Figure 1-2This embodiment describes a guide device for a water-plate heat exchanger 7 installed in the 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 sidewall of the flue is connected to the boiler steel column 4. It includes a guide steel plate 3, a guide rod 2, a pin, and ear plates. The ear plates include 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. Both the first ear plate 9 and the second ear plate 10 are provided with through holes. The ear plates provide fixing points for the pin. The hydraulic pressure is distributed 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 use of pins replaces traditional welding, avoiding the thermal stress generated by direct welding between the water plate heat exchanger 7 and the boiler steel column 4 and the chimney 1. The guide steel plate 3 is located 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 to the rear of the furnace, the guide steel plate 3 is subjected to tension and transmits the thrust. The guide steel plate 3, connected to the boiler steel column 4, prevents the water plate heat exchanger 7 from moving backward. The guide steel plate 3, through the connection of the first pin 5, constrains the water plate heat exchanger 7 to move backward under horizontal force, thereby maintaining the stability of the water plate heat exchanger 7's position. The guide rod 2 is located 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 tensile force is generated in the direction from the rear to the front of the furnace, the guide rod 2 is subjected to tensile force and transmits this force to the chimney 1, preventing the water plate heat exchanger 7 from moving forward. 2. The water plate heat exchanger 7 is constrained by the connection of the second pin 6 to move 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 under thermal expansion, thereby allowing the water plate heat exchanger 7 to achieve free expansion and contraction at high temperature, 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 to ensure that the horizontal force transmission is not interrupted.

[0025] The working principle of this invention is as follows:

[0026] The guiding device of this invention achieves 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 the water-plate heat exchanger with a workpiece that can freely expand and contract. The size of this 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 to the rear of the furnace, the guide steel plate 3 set at the front end of the water-plate heat exchanger 7 is subjected to tension. This tension is transmitted through the first pin 5 to the first ear plate 9 welded to the side of the boiler steel column 4, and finally the boiler steel column 4 bears the load. At this time, the guide steel plate 3 constrains the water-plate heat exchanger. The heat exchanger 7 is displaced backward to maintain the stability of its position. When a sudden load such as an earthquake generates a horizontal force from the rear to the front of the furnace, the guide rod 2 located behind the heat exchanger 7 is subjected to tension. This tension is transmitted through the second pin 6 to the second ear plate 10 welded to the side of the chimney 1, where the chimney 1 bears the load. 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 reliable dissipation of horizontal force under different operating conditions. Throughout the process, the pin connection replaces the traditional welded structure, maintaining the expansion gap function while transmitting horizontal force, so that the water plate heat exchanger 7 achieves dynamic balance between thermal expansion and mechanical constraint, ensuring long-term safe operation of the equipment.

[0027] The number of guide steel plates 3 is determined based on the horizontal tensile force generated by the flue gas flow and the rated tensile force of a single guide steel plate 3. That is, the total load-bearing capacity of all guide steel plates 3 needs to be greater than the maximum horizontal tensile force generated by the flue gas. The rated tensile force 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 implementation.

[0028] The number of guide rods 2 is the same as the number of guide steel plates 3, and the guide rods 2 and guide steel plates 3 are symmetrically arranged along the water plate heat exchanger 7. The fact that the number of guide rods 2 is the same as the number of guide steel plates 3 ensures that the maximum load-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 guide steel plates 3 radially distributed along the axis of the water plate heat exchanger 7, ensuring that the horizontal force application point is symmetrical. If it is 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.

[0029] There are multiple first ear plates 9, which are welded at equal intervals to the side of the boiler steel column 4. The horizontal tensile force of flue gas transmitted by the guide steel plate 3 is finally distributed to the boiler steel column 4 through the first ear plates 9. If only a single first ear plate 9 is set, the concentrated load is likely to cause the local stress of the ear plate weld or 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.

[0030] There are multiple second ear plates 10, which are welded at equal intervals to the side of the chimney 1. The horizontal force transmitted by the guide rod 2 from the rear of the furnace to the front of the furnace needs to be distributed to the chimney 1 through the second ear plates 10. The parallel arrangement of multiple second ear plates 10 can evenly distribute the total tensile force to the bearing surface of the chimney 1, reduce the stress at a single point, and the equal spacing makes each second ear plate 10 bear the force evenly, avoiding overload of some second ear plates 10 due to uneven spacing.

[0031] Both the guide steel plate 3 and the guide rod 2 are made of high-temperature resistant steel, which can be selected from materials such as boiler pressure vessel steel plates or heat-resistant alloy structural steel.

[0032] 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. Due to the welding of the flue plate 8, there is a local reinforcement effect in this area. Welding the first ear plate 9 to this position can directly utilize the ultra-high rigidity of this area to transfer horizontal force and avoid deformation of the non-node area of ​​the boiler steel column 4 due to insufficient load-bearing capacity.

[0033] The second ear plate 10 is welded to the side of the chimney 1 near the flue plate 8. The reverse horizontal force transmitted by the guide rod 2 needs to be distributed 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 force from being transmitted along the long distance of the chimney 1 wall and generating additional bending moment.

[0034] The specific embodiments of the present invention disclosed above are merely illustrative of the invention. These embodiments do not exhaustively describe all details, nor do they limit the invention to the specific embodiments described. Many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. A guide device for a water-plate heat exchanger installed 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) on the side wall of the flue is connected to the boiler steel column (4), characterized in that: It includes a guide steel plate (3), a guide rod (2), a pin, and an ear plate; the ear plate includes 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 both the first ear plate (9) and the second ear plate (10) are provided with through holes; the pin includes 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 located 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); the guide rod (2) is located 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); the inner wall of the through hole on the ear plate and the outer wall of the corresponding pin form an axial expansion gap, 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. The water plate heat exchanger guiding device installed in the boiler outlet flue according to claim 1, characterized in that: The number of 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).

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

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

5. A water plate heat exchanger guiding device installed in the boiler outlet flue according to claim 1, characterized in that: There are multiple second ear plates (10), and multiple second ear plates (10) are welded at equal intervals to the side of the chimney (1).

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

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

8. A water plate heat exchanger guiding device installed in the boiler outlet flue according to claim 1, characterized in that: The second ear plate (10) is welded to the side of the chimney (1) near the flue plate (8).

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