A waste gas guide circulation assembly of a high-efficiency energy-saving heat treatment device

Abstract

This utility model provides a waste gas guiding and circulation component for a high-efficiency and energy-saving heat treatment device, belonging to the technical field of high-efficiency and energy-saving heat treatment devices. The waste gas guiding and circulation component includes a guiding shell, swirl blades, a return pipe, and a sealing ring. The guiding shell has a frustum-shaped structure, with its large port connected to the waste gas discharge port of the heat treatment device and its small port connected to the inlet of the return pipe. The swirl blades are disposed within the inner cavity of the guiding shell and have a propeller-like structure, with the blade surface of the swirl blades forming an inclined angle with the axis of the guiding shell. This invention solves the technical problems of low guiding efficiency and severe heat loss in the recycling process of high-temperature waste gas emitted by heat treatment devices in the prior art.

Description

Technical Field

[0001] This utility model belongs to the technical field of high-efficiency and energy-saving heat treatment devices, specifically, it relates to a waste gas guiding and circulation component of a high-efficiency and energy-saving heat treatment device. Background Technology

[0002] Heat treatment equipment is widely used in industries such as metal processing, ceramic sintering, and glass melting. These devices consume significant amounts of energy to maintain the high-temperature environment during operation, generating large quantities of high-temperature exhaust gases. These gases, typically between 400°C and 800°C, carry substantial heat energy. Direct release into the atmosphere not only wastes energy but also causes thermal pollution. Therefore, waste gas recovery and utilization is crucial for energy conservation and emission reduction in heat treatment equipment. Currently, common industrial waste gas recovery methods primarily involve guiding the waste gas through pipelines to heat exchangers or directly returning it to the heat treatment unit for secondary utilization. Existing waste gas guiding devices mostly employ straight pipe connections or simple 90° bend connections. While these structures are simple to manufacture and inexpensive, they have significant technical drawbacks in practical use. Although straight pipe connections offer lower flow resistance, they also present certain limitations. The inability to effectively guide the flow of exhaust gas results in a disordered flow within the pipeline. When the exhaust gas velocity is high, strong eddies and turbulence are easily generated at pipe bends or diameter changes. This disordered flow not only increases energy loss and reduces exhaust gas transport efficiency, but also shortens the residence time of the exhaust gas within the pipeline, leading to insufficient heat exchange with the pipe wall. Although simple bend-type connections can change the direction of exhaust gas flow, airflow separation and secondary flow phenomena are prone to occur at bends, which also increase flow resistance and heat loss. In addition, existing flow guiding devices typically use flange connections or simple plug-in methods when connecting to the exhaust port of the heat treatment device. The sealing performance of these connection methods is often not ideal, and the sealing materials are prone to aging and failure in high-temperature environments, resulting in exhaust gas leakage at the connection. The leaked high-temperature exhaust gas not only wastes heat energy but may also pose a safety hazard to operators. Utility Model Content

[0003] In view of this, the present invention provides a waste gas guiding and circulation component for a high-efficiency and energy-saving heat treatment device. This component solves the problem that existing heat treatment devices typically use straight pipe or simple bent pipe guiding structures for high-temperature waste gas recovery. Such structures cannot effectively control the direction and speed of waste gas flow, resulting in a large number of eddies and backflow phenomena during the guiding process. This not only increases flow resistance and reduces waste gas transport efficiency, but also results in insufficient heat exchange due to the short contact time between the waste gas and the pipe wall during disordered flow. In addition, traditional guiding structures have poor sealing performance when connected to the exhaust port of the heat treatment device, which easily leads to waste gas leakage at the connection point, causing heat to be wasted. These problems seriously affect the energy utilization rate and energy-saving effect of the heat treatment device.

[0004] This utility model is implemented as follows:

[0005] This utility model provides a waste gas guiding and circulation component for a high-efficiency and energy-saving heat treatment device, used for waste gas recovery and utilization in the heat treatment device. It includes a guiding shell, swirl blades, a return pipe, and a sealing ring. The guiding shell has a frustum-shaped structure, with its large port connected to the waste gas discharge port of the heat treatment device, and its small port connected to the air inlet of the return pipe. The swirl blades are disposed within the inner cavity of the guiding shell and have a propeller-like structure. The blade surfaces of the swirl blades form an inclined angle with the axis of the guiding shell. The sealing ring is disposed at the connection between the guiding shell and the waste gas discharge port of the heat treatment device. The inner diameter of the sealing ring is smaller than the inner diameter of the large port of the guiding shell. The sealing ring is fixed to the end face of the guiding shell by multiple evenly distributed fastening bolts.

[0006] The technical effects of the exhaust gas guiding and circulation component of the high-efficiency and energy-saving heat treatment device provided by this utility model are as follows: By adopting a frustum-shaped structure for the guiding shell and combining it with a propeller-shaped design of swirling blades, the high-temperature exhaust gas emitted by the heat treatment device can form a rotating airflow after entering the guiding shell. The frustum-shaped structure allows the airflow to gradually accelerate and enhance the rotation intensity as it flows towards the small port. The tilt angle design of the swirling blades can effectively guide the direction of exhaust gas flow. The sealing ring ensures the airtightness of the connection between the guiding shell and the exhaust port of the heat treatment device, preventing exhaust gas leakage and heat loss. The connection structure between the return pipe and the small port of the guiding shell realizes the directional guidance of exhaust gas. The overall component structure is simple and easy to install, which can effectively improve the efficiency of exhaust gas recovery and utilization.

[0007] Based on the above technical solution, the waste gas guiding and circulation component of the high-efficiency energy-saving heat treatment device of this utility model can be further improved as follows:

[0008] The swirl blades consist of three blades, which are evenly distributed at 120° along the axis of the guide shell.

[0009] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: The structural design of three swirl blades evenly distributed at 120° along the axis of the guide shell ensures that the exhaust gas is subjected to uniform force when passing through the swirl blade area, avoiding the airflow deflection problem caused by single-sided or double-sided blade arrangement. The uniform distribution angle of 120° enables the exhaust gas to form a stable spiral upward airflow within the frustum-shaped guide shell. The configuration of three blades ensures sufficient guiding effect while avoiding increased flow resistance caused by too many blades, allowing the exhaust gas to be fully mixed and maintain a high flow velocity during rotation.

[0010] Furthermore, the blade surface of the swirl blade is an arc-shaped curved surface structure, with the concave surface of the arc-shaped curved surface facing the small port of the guide shell.

[0011] The beneficial effects of the above-mentioned improvement scheme are as follows: The blade surface of the swirl blade adopts an arc-shaped curved surface structure with the concave surface facing the direction of the small port of the guide shell, which allows the exhaust gas to smoothly transition along the arc-shaped curved surface when it comes into contact with the blade surface. The arc-shaped curved surface structure can reduce the impact and turbulence between the exhaust gas and the blade surface. The concave surface design makes the thrust generated by the exhaust gas on the blade surface consistent with the direction of airflow. This structure can effectively reduce the energy loss during the exhaust gas flow process, while enhancing the stability of the rotating airflow and improving the residence time and heat exchange efficiency of the exhaust gas in the guide shell.

[0012] Furthermore, the inner wall surface of the flow guide shell is provided with multiple flow guide ribs, which extend along the axial direction of the flow guide shell, and the height of the flow guide ribs gradually decreases from the large port to the small port of the flow guide shell.

[0013] The beneficial effects of the above-mentioned improvement scheme are as follows: The structural design of multiple guide ribs extending axially along the inner wall of the guide shell and gradually decreasing in height from the large port to the small port allows the exhaust gas to be guided by the guide ribs when flowing near the inner wall of the guide shell. The axial extension of the guide ribs can prevent the exhaust gas from generating backflow or eddy currents at the inner wall. The gradually decreasing height of the ribs, combined with the cross-sectional contraction of the frustum-shaped guide shell, makes the change of the exhaust gas flow channel smoother. This structure can keep the exhaust gas in a laminar flow state in the guide shell, reduce flow resistance and improve the guiding efficiency.

[0014] Furthermore, the gap between the outer edge of the swirl blade and the inner wall of the guide shell gradually decreases from the large port to the small port along the axial direction of the guide shell.

[0015] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: The structural design of the gap between the outer edge of the swirl blade and the inner wall of the guide shell gradually decreasing from the large port to the small port along the axial direction allows the exhaust gas to be gradually compressed and accelerated when passing through the swirl blade area. The gradual change in gap distance can prevent a large amount of exhaust gas from leaking out from the gap between the outer edge of the blade and the inner wall. At the same time, this gradual gap structure, combined with the cross-sectional contraction of the frustum-shaped guide shell, allows the exhaust gas to maintain a stable rotation speed and flow direction throughout the entire guiding process, improving the uniformity and controllability of the exhaust gas guiding, and reducing local eddies and energy loss.

[0016] Furthermore, the air inlet of the return pipe has a flared structure in the shape of a trumpet, and the maximum diameter of the flared structure is equal to the outer diameter of the small port of the guide shell.

[0017] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: The design of the inlet end of the return pipe adopting a trumpet-shaped flared structure with the maximum diameter being equal to the outer diameter of the small port of the guide shell allows the rotating exhaust gas flowing out from the small port of the guide shell to smoothly enter the return pipe. The trumpet-shaped flared structure can gradually reduce the rotation speed of the exhaust gas and convert the rotational kinetic energy into axial flow kinetic energy. The size matching of the flared opening and the outer diameter of the small port of the guide shell ensures the continuity of airflow at the connection between the two, avoiding airflow separation and pressure loss caused by abrupt changes in cross-section. This structural design can improve the smoothness and flow efficiency of the exhaust gas transition from the guide shell to the return pipe.

[0018] Furthermore, the sealing ring has a rectangular cross-sectional shape, and a groove is provided on the outer circumference of the sealing ring. The screw part of the fastening bolt passes through the groove and is screwed into the threaded hole of the flow guide housing.

[0019] The beneficial effects of the above-mentioned improved scheme are as follows: The sealing ring adopts a rectangular cross-section shape and has a groove on the outer circumference. The fastening bolt passes through the groove and is screwed into the threaded hole of the flow guide shell. This connection structure allows the sealing ring to be evenly pressed on the connection surface between the flow guide shell and the exhaust port of the heat treatment device. The rectangular cross-section provides sufficient sealing contact area. The groove allows the fastening bolt to be accurately positioned without affecting the sealing function of the sealing ring. This structural design ensures the reliability of the connection and facilitates the disassembly and replacement of the sealing ring. At the same time, the even distribution of multiple fastening bolts can make the sealing ring bear force evenly, improving the overall sealing effect.

[0020] Furthermore, the flow guide housing is made of high-temperature resistant stainless steel.

[0021] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: the flow guide shell is made of high-temperature resistant stainless steel, which can withstand the long-term action of high-temperature exhaust gas emitted by the heat treatment device without deformation or oxidation corrosion. The high-temperature resistant stainless steel has good mechanical strength and thermal stability, which can ensure that the flow guide shell maintains structural integrity and dimensional stability in high-temperature environment. The corrosion resistance of stainless steel can resist the erosion of acidic or alkaline components that may be contained in the exhaust gas, extending the service life of the flow guide shell. At the same time, the surface smoothness of stainless steel helps to reduce the flow resistance of exhaust gas and improve the flow guiding efficiency.

[0022] Furthermore, the root of the swirl blade is fixedly connected to the inner wall of the guide shell by welding, and the weld is continuously distributed along the entire edge of the blade root.

[0023] The beneficial effects of adopting the above-mentioned improvement scheme are as follows: The connection structure in which the blade root of the swirl blade is fixedly connected to the inner wall of the guide shell by welding and the weld seam is continuously distributed along the entire edge of the blade root makes the swirl blade and the guide shell form an integrated whole structure. The welding connection method can withstand the large impact force and vibration load generated by the exhaust gas flow. The design of the weld seam being continuously distributed along the entire edge of the blade root ensures the uniformity of the connection strength and avoids stress concentration and weak points caused by local welding. This connection method can also eliminate the gap between the blade root and the inner wall surface, preventing the exhaust gas from generating eddies and energy loss at the gap.

[0024] Furthermore, the cone angle of the frustum-shaped structure of the flow guide shell is 15~25°, and the inclination angle between the blade surface of the swirl blade and the axis of the flow guide shell is 35~45°.

[0025] The beneficial effects of adopting the above-mentioned improved scheme are as follows: the combination of parameters, with the cone angle of the frustum-shaped structure of the guide shell set in the range of 15~25° and the inclination angle between the blade surface of the swirl blade and the axis of the guide shell set in the range of 35~45°, enables the exhaust gas to form an optimal spiral flow state within the guide shell. Within this range, the cone angle allows the exhaust gas to maintain a stable flow pattern during acceleration without generating excessive turbulence. Within this range, the blade inclination angle provides appropriate rotational torque to the exhaust gas without causing excessive flow resistance. The synergistic combination of these two angle parameters enables the exhaust gas to obtain sufficient rotational and axial kinetic energy within the guide shell, achieving efficient exhaust gas guidance and heat recovery.

[0026] Compared with existing technologies, the beneficial effects of the waste gas guiding and circulating component of the high-efficiency energy-saving heat treatment device provided by this utility model are as follows: This utility model fundamentally changes the flow state of waste gas during the guiding process by adopting a combination structure of a frustum-shaped guiding shell and a propeller-shaped swirling blade. The frustum-shaped structure causes the waste gas flow channel to gradually narrow from the large end to the small end. This narrowing structure can accelerate and compress the waste gas. The propeller-shaped swirling blades give the waste gas rotational kinetic energy while accelerating, forming a stable spiral airflow. This spiral airflow not only allows the waste gas to maintain a high flow velocity within the guiding shell, but also the rotational motion makes the contact between the waste gas and the inner wall of the guiding shell more sufficient, significantly improving the heat exchange efficiency. The inner wall of the guiding shell is designed with... The design of the guide ribs and the gradual gap between the outer edge of the swirl blades and the inner wall further optimizes the exhaust gas flow path, effectively eliminating eddies and backflow phenomena, and reducing flow resistance. The combination of the sealing ring and fastening bolts, as well as the flared design of the inlet end of the backflow pipe, ensures the airtightness and flow continuity of the entire exhaust gas guiding and circulation system, preventing heat leakage. The use of high-temperature resistant stainless steel and welding connection methods gives the entire component excellent high-temperature stability and structural reliability, enabling long-term stable operation under the harsh conditions of heat treatment equipment. Compared with traditional straight pipe or simple bent pipe guiding structures, this utility model can improve the exhaust gas guiding efficiency and significantly improve the heat recovery rate. At the same time, the structure is simple and compact, and the installation and maintenance are convenient, making it of good engineering application value. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A schematic diagram of the structure of a waste gas diversion and circulation component of a high-efficiency and energy-saving heat treatment device;

[0029] Figure 2 This is a schematic diagram of the sealing ring structure;

[0030] Figure 3 This is a schematic diagram of the cross-section of the flow guide shell;

[0031] The attached diagram lists the components represented by each number as follows:

[0032] 10. Flow guide shell; 20. Swirl blades; 30. Return pipe; 40. Sealing ring; 41. Fastening bolts. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.

[0034] like Figure 1-3 The diagram shows a schematic of the exhaust gas guiding and circulation component of a high-efficiency and energy-saving heat treatment device provided by this utility model. In the diagram, the component for exhaust gas recovery and utilization in the heat treatment device includes a guiding shell 10, swirl blades 20, a return pipe 30, and a sealing ring 40. The guiding shell has a frustum-shaped structure. The large port of the guiding shell is connected to the exhaust gas outlet of the heat treatment device, and the small port of the guiding shell is connected to the inlet of the return pipe. The swirl blades are set in the inner cavity of the guiding shell and have a propeller-shaped structure. The blade surface of the swirl blades forms an inclined angle with the axis of the guiding shell. The sealing ring is set at the connection between the guiding shell and the exhaust gas outlet of the heat treatment device. The inner diameter of the sealing ring is smaller than the inner diameter of the large port of the guiding shell. The sealing ring is fixed to the end face of the guiding shell by multiple evenly distributed fastening bolts 41.

[0035] In the above technical solution, the number of swirl blades is 3, and the 3 swirl blades are evenly distributed at 120° along the axis of the guide shell.

[0036] Furthermore, in the above technical solution, the blade surface of the swirl blade is an arc-shaped curved surface structure, with the concave surface of the arc-shaped curved surface facing the direction of the small port of the guide shell.

[0037] Furthermore, in the above technical solution, the inner wall surface of the flow guide shell is provided with multiple flow guide ribs, which extend along the axial direction of the flow guide shell, and the height of the flow guide ribs gradually decreases from the large port to the small port of the flow guide shell.

[0038] Furthermore, in the above technical solution, the gap between the outer edge of the swirl blade and the inner wall of the guide shell gradually decreases from the large port to the small port along the axial direction of the guide shell.

[0039] Furthermore, in the above technical solution, the air inlet end of the return pipe has a flared structure, and the maximum diameter of the flared structure is equal to the outer diameter of the small port of the guide shell.

[0040] Furthermore, in the above technical solution, the sealing ring has a rectangular cross-sectional shape, and the outer ring of the sealing ring is provided with a groove in the circumference. The screw part of the fastening bolt passes through the groove and is screwed into the threaded hole of the flow guide housing.

[0041] Furthermore, in the above technical solution, the flow guide shell is made of high-temperature resistant stainless steel.

[0042] Furthermore, in the above technical solution, the root of the swirl blade is fixedly connected to the inner wall of the guide shell by welding, and the weld is continuously distributed along the entire edge of the blade root.

[0043] Furthermore, in the above technical solution, the cone angle of the frustum-shaped structure of the flow guide shell is 15~25°, and the inclination angle between the blade surface of the swirl blade and the axis of the flow guide shell is 35~45°.

[0044] The following is a specific embodiment 1 of this utility model. In this embodiment, the waste gas guiding and circulating component is applied to the waste gas recovery system of a metal heat treatment furnace. The guiding shell is made of high-temperature resistant stainless steel 304. The overall length of the guiding shell is 450mm, the inner diameter of the large port is 280mm, the inner diameter of the small port is 160mm, the cone angle of the frustum-shaped structure is 20°, and the wall thickness of the guiding shell is 5mm. Eight guiding ribs are evenly distributed along the axial direction on the inner wall surface of the guiding shell. The width of each guiding rib is 15mm, the height of the rib at the large port is 8mm, and the height at the small port is 3mm. The height of the ribs decreases linearly along the axial direction. The swirl blades are also made of 304 stainless steel, and there are three swirl blades. Three blades are evenly distributed at 120° along the axis of the guide shell. Each swirl blade is 380mm long, with a width of 90mm near the large end and 50mm near the small end, gradually decreasing in width along the axial direction. The blade is 4mm thick and has an arc-shaped curved surface with a radius of curvature of 200mm. The concave surface faces the small end of the guide shell, and the blade surface is tilted at 40° to the axis of the guide shell. The root of the swirl blade is welded to the inner wall of the guide shell using argon arc welding, with a weld width of 6mm. The weld is continuous along the entire edge of the blade root without any breaks. The gap between the outer edge of the swirl blade and the inner wall of the guide shell at the large end is 25mm. The gap at the small port is 10mm, decreasing linearly along the axial direction. The sealing ring is made of high-temperature wear-resistant ceramic fiber material, with a rectangular cross-section of 30mm width and 20mm height. The inner diameter of the sealing ring is 270mm, and the outer diameter is 340mm. Twelve grooves are evenly distributed around the outer circumference of the sealing ring, each 15mm wide and 8mm deep. Twelve high-strength M10 bolts are used for fastening, corresponding one-to-one with the grooves on the sealing ring. The return pipe is made of seamless steel pipe with an outer diameter of 180mm and a wall thickness of 6mm. The air inlet of the return pipe is flared into a trumpet shape with a maximum diameter of 280mm. The outer diameter of the small port of the guide shell is equal to that of the guide shell, and the length of the flare is 150mm. The inner surface of the flare is polished to reduce airflow resistance. During installation, align the large port of the guide shell with the exhaust port of the metal heat treatment furnace, place a sealing ring between them, and tighten 12 fastening bolts in a diagonal, alternating sequence. The tightening torque of each bolt is 45 Nm. Then, insert the flared end of the return pipe onto the outside of the small port of the guide shell and fix it with a flange connection. When the metal heat treatment furnace is working, the furnace temperature is 650℃, and the exhaust gas temperature is approximately 550℃. After the exhaust gas enters the guide shell from the exhaust port, it forms a clockwise rotating spiral airflow under the action of the swirl blades. The spiral airflow accelerates in the frustum-shaped channel and makes full contact with the inner wall surface.The residence time of the exhaust gas within the guide shell is approximately 2.5 seconds. During this period, the exhaust gas temperature drops to 480℃. The heat is absorbed by the guide shell and dissipated through its outer surface or recovered by an external cooling system. After exiting from the small port, the exhaust gas enters the return pipe, where its rotational speed decreases within the flared opening. Finally, it enters the subsequent heat exchanger with lower rotational intensity and higher axial velocity. The entire guide circulation assembly operates smoothly, with unobstructed exhaust gas flow and no significant eddies or backflow. The sealing ring maintains good sealing performance under high-temperature conditions, and there is no exhaust gas leakage at the connections. The guide shell and swirl blades maintain structural stability during continuous operation, without deformation or cracking.

[0045] The following is another specific embodiment 2 of this utility model. This embodiment 2 is based on embodiment 1, and the structure of the swirl blade is improved. In this embodiment, the number of swirl blades is increased to 4. The 4 blades are evenly distributed at 90° along the axis of the guide shell. The blade surface of each swirl blade adopts a hyperboloid structure. The first arc-shaped surface with a radius of curvature of 180 mm is located in the third area near the root of the blade. The middle 1 / 3 area is a transition plane. The second arc-shaped surface with a radius of curvature of 220 mm is located in the third area near the outer edge of the blade. The concave surfaces of the two arc-shaped surfaces are in the same direction, both facing the small port of the guide shell. This hyperboloid structure makes the exhaust gas subject to a more complex guiding effect when passing through the blade. The exhaust gas is subject to a stronger rotational torque in the root area of ​​the blade and a gentler guiding effect in the outer edge area of ​​the blade. The hyperboloid structure can better guide exhaust gas with different flow velocities.

[0046] Specifically, the principle of this utility model is as follows: The core of this utility model lies in the use of a specially designed combination structure of a guide shell and swirl blades to transform disordered high-temperature exhaust gas into an ordered spiral airflow, thereby improving the guiding efficiency and heat recovery rate. The guide shell adopts a frustum-shaped structure, with its large port connected to the exhaust port of the heat treatment device and its small port connected to the return pipe. This gradually decreasing cross-section design conforms to the contraction tube principle in fluid mechanics. When the exhaust gas enters the guide shell from the large port, as the flow cross-section gradually decreases, according to the law of conservation of mass and Bernoulli's equation, the flow velocity of the exhaust gas... The temperature gradually increases while the pressure gradually decreases. This acceleration effect allows the exhaust gas to maintain high flow kinetic energy within the guide shell, reducing the accumulation and stagnation of exhaust gas in the pipe. The swirl blades are located within the inner cavity of the guide shell. Their propeller-like structure and inclined angle design cause the exhaust gas to experience tangential force as it passes through the blade area. This tangential force causes the exhaust gas to rotate while flowing axially, forming a spiral airflow. The rotational motion of the spiral airflow causes the exhaust gas to advance along a spiral trajectory within the guide shell. This motion significantly increases the flow path length of the exhaust gas within the guide shell, extending its range. The spiral airflow significantly improves the heat exchange efficiency between the exhaust gas and the inner wall of the guide shell, based on the principle of heat transfer that heat transfer efficiency is directly proportional to the heat transfer area and contact time. Simultaneously, the centrifugal force of the spiral airflow throws particulate matter and impurities in the exhaust gas onto the inner wall of the guide shell, facilitating subsequent filtration and cleaning. The guide ribs on the inner wall of the guide shell stabilize and guide the spiral airflow, preventing unstable swaying or detachment during rotation. The gradually varying height of the ribs, combined with the frustum-shaped structure, ensures that the airflow... The gradual gap design between the outer edge of the swirl blades and the inner wall of the guide shell ensures a smooth transition during acceleration and rotation. This design not only guarantees the guiding effect of the blades on the exhaust gas but also prevents increased flow resistance caused by excessively small gaps. The sealing ring adopts a rectangular cross-section and is connected by multiple fastening bolts that are evenly tightened. This design can maintain good sealing performance in high-temperature environments and prevent exhaust gas from leaking from the connection. The flared structure at the air inlet of the return pipe allows the high-speed rotating exhaust gas to gradually slow down when entering the return pipe and converts the rotational kinetic energy into axial flow kinetic energy, avoiding energy loss caused by abrupt changes in cross-section.

[0047] In use, first select the appropriate model of exhaust gas guide circulation assembly according to the size and specifications of the exhaust gas outlet of the heat treatment device. Align the large port of the guide housing with the exhaust gas outlet of the heat treatment device. Place a sealing ring between the two connecting surfaces. The inner ring of the sealing ring should completely cover the effective ventilation area of ​​the outlet. Then, use a wrench or power tool to screw multiple fastening bolts into the threaded holes on the end face of the guide housing in sequence. When tightening the bolts, use a diagonal and crisscrossing sequence to gradually increase the force, ensuring that the sealing ring is evenly stressed and does not skew. Finally, tighten all bolts to the specified torque value. After installation, check for gaps or deformation around the sealing ring to confirm that the sealing effect is good. Next, connect the inlet end of the return pipe to the small port of the guide housing. The flared end of the return pipe should be completely fitted into the outside of the small port of the guide housing. Use pipe connectors or welding to fix the two together. When connecting, ensure that the axis of the return pipe is aligned with that of the guide housing to avoid skew or misalignment. After installation, start the heat treatment device to begin normal operation. High-temperature exhaust gas flows from the heat treatment device. After being discharged internally, the exhaust gas enters the large port of the guide shell. Inside the guide shell, the exhaust gas is first guided by the swirl blades. The propeller-like structure and tilt angle of the blades allow the exhaust gas to gain rotational kinetic energy while flowing axially, forming a stable spiral airflow. The spiral airflow accelerates forward in the frustum-shaped channel of the guide shell, while simultaneously exchanging heat with the inner wall of the guide shell. After flowing out from the small port of the guide shell, the exhaust gas enters the funnel-shaped flare of the return pipe. Inside the flare, the rotational speed of the exhaust gas gradually decreases and transforms into axial flow. Finally, it returns to the heat treatment unit or enters the heat exchanger for further heat utilization through the return pipe. The entire exhaust gas guiding and circulation process does not require an additional power unit and is driven entirely by the exhaust gas discharge pressure of the heat treatment unit itself. During use, the condition of the sealing ring and fastening bolts should be checked regularly. If the sealing ring is found to be aged or the bolts are loose, they should be replaced or tightened in time. The inside of the guide shell should be cleaned at regular intervals to remove the dust and impurities adhering to the inner wall and swirl blades to maintain good guiding effect.

Claims

1. A waste gas guiding and circulation assembly for a high-efficiency and energy-saving heat treatment device, used for waste gas recovery and utilization in the heat treatment device, comprising a guiding shell, swirl vanes, a return pipe, and a sealing ring, wherein the guiding shell has a frustum-shaped structure, the large port of the guiding shell is connected to the waste gas discharge port of the heat treatment device, and the small port of the guiding shell is connected to the inlet end of the return pipe, characterized in that, The swirl blades are set in the inner cavity of the guide shell. The swirl blades have a propeller-like structure. The blade surface of the swirl blades forms an inclined angle with the axis of the guide shell. The sealing ring is set at the connection between the guide shell and the exhaust port of the heat treatment device. The inner diameter of the sealing ring is smaller than the inner diameter of the large port of the guide shell. The sealing ring is fixed to the end face of the guide shell by multiple evenly distributed fastening bolts.

2. The waste gas guiding and circulation assembly of a high-efficiency energy-saving heat treatment device according to claim 1, characterized in that, The swirl blade has three blades, which are evenly distributed at 120° along the axis of the guide shell.

3. The waste gas guiding and circulation component of a high-efficiency energy-saving heat treatment device according to claim 2, characterized in that, The blade surface of the swirl blade is an arc-shaped curved surface structure, with the concave side of the arc-shaped curved surface facing the small port of the guide shell.

4. The waste gas guiding and circulation component of a high-efficiency energy-saving heat treatment device according to claim 3, characterized in that, The inner wall of the flow guide shell is provided with multiple flow guide ribs, which extend along the axial direction of the flow guide shell, and the height of the flow guide ribs gradually decreases from the large port to the small port of the flow guide shell.

5. The waste gas guiding and circulation assembly of a high-efficiency energy-saving heat treatment device according to claim 4, characterized in that, The gap between the outer edge of the swirl blade and the inner wall of the guide shell gradually decreases from the large port to the small port along the axial direction of the guide shell.

6. The waste gas guiding and circulation assembly of a high-efficiency energy-saving heat treatment device according to claim 5, characterized in that, The air inlet of the return pipe has a flared, trumpet-shaped structure, and the maximum diameter of the flared structure is equal to the outer diameter of the small port of the guide shell.

7. The waste gas guiding and circulation assembly of a high-efficiency energy-saving heat treatment device according to claim 6, characterized in that, The sealing ring has a rectangular cross-sectional shape, and a groove is provided on the outer circumference of the sealing ring. The screw part of the fastening bolt passes through the groove and is screwed into the threaded hole of the flow guide housing.

8. The waste gas guiding and circulation assembly of a high-efficiency energy-saving heat treatment device according to claim 7, characterized in that, The flow guide housing is made of high-temperature resistant stainless steel.

9. The waste gas guiding and circulation component of a high-efficiency energy-saving heat treatment device according to claim 8, characterized in that, The root of the swirl blade is fixedly connected to the inner wall of the guide shell by welding, and the weld is continuously distributed along the entire edge of the blade root.

10. The waste gas guiding and circulation component of a high-efficiency energy-saving heat treatment device according to claim 9, characterized in that, The cone angle of the frustum-shaped structure of the flow guide shell is 15~25°, and the inclination angle between the blade surface of the swirl blade and the axis of the flow guide shell is 35~45°.

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