A medium-frequency furnace cavity with equal air intake

Abstract

This utility model relates to the technical field of medium-frequency furnace supporting equipment, and discloses a medium-frequency furnace cavity with equally divided air intake, including an air intake plate, an 8-hole layered plate, a 12-hole layered plate, a 32-hole outlet plate, a middle insulation layer, and a top cover. The air intake plate, the 8-hole layered plate, the 12-hole layered plate, and the 32-hole outlet plate are stacked and fixedly connected from bottom to top to form a multi-stage flow distribution base. The middle insulation layer is set on top of the 32-hole outlet plate. The 8-hole layered plate, the 12-hole layered plate, and the 32-hole outlet plate are respectively provided with 8, 16, and 32 uniform through holes, and guide grooves are reserved between each layer. This utility model achieves all-round, dead-angle-free airflow around the bar stock through a multi-stage flow distribution structure, significantly improving the hydrogen impurity removal efficiency. At the same time, the uniform airflow field drives heat transfer, greatly reducing the temperature difference between different parts of the bar stock, and effectively ensuring the consistency of product grain growth.

Description

Technical Field

[0001] This utility model relates to the technical field of medium-frequency furnace supporting equipment, and in particular to a medium-frequency furnace cavity with equal gas intake. Background Technology

[0002] As a key piece of equipment for metal smelting and heat treatment, medium-frequency furnaces are widely used in the heating and purification processes of various metal bars. In order to remove impurities from the material and improve its purity, reducing gases such as hydrogen need to be introduced into the furnace cavity to create a specific reaction atmosphere. Most existing medium-frequency furnace cavity gas inlet structures adopt the traditional single-channel bottom gas inlet method, that is, the gas source is directly introduced into the heat preservation area inside the furnace cavity through a single gas inlet pipe.

[0003] However, this single-point centralized air intake structure has obvious airflow distribution defects in practical applications. Since the gas only enters from one position, the high-speed flowing gas is difficult to fill the entire cross-section of the furnace cavity in a short time. This results in a non-uniform flow field with high velocity in the middle and low velocity around the edges inside the furnace cavity. The surface of the bar placed vertically in the furnace cavity cannot be uniformly flushed by the gas. This means that some areas of the bar can fully contact and react with hydrogen, while other areas are in the gas contact blind zone. As a result, the overall impurity removal effect of the bar is inconsistent and incomplete.

[0004] This uneven airflow distribution will further cause instability in the thermal field inside the furnace cavity. Uneven airflow will lead to a large difference in the convective heat transfer coefficient at different parts of the bar, which in turn will create a significant temperature gradient between different parts of the bar. Since the growth state of the grains is closely related to the temperature environment, a large temperature difference will lead to inconsistent grain growth rates at different parts of the bar, ultimately resulting in poor uniformity of the grain structure of the produced metal bar, which is difficult to meet the requirements of high-quality industrial production.

[0005] Therefore, this utility model proposes a medium-frequency furnace cavity with equal air intake to overcome the shortcomings of the prior art. Utility Model Content

[0006] In view of the problems in the existing medium-frequency furnace cavity using a single-channel air intake structure, such as uneven airflow distribution across the furnace cavity cross-section, large local flow velocity differences leading to dead contact angles on the bar surface and incomplete impurity removal, and unstable thermal field caused by uneven airflow distribution resulting in large temperature differences and poor grain growth uniformity in different parts of the bar, this utility model aims to provide a medium-frequency furnace cavity with an improved structure that can effectively solve the above problems by providing equal-division air intake.

[0007] This utility model provides a medium-frequency furnace cavity with equal air intake, comprising: an air intake plate, an 8-hole layered plate fixedly connected to the top of the air intake plate, a 12-hole layered plate fixedly connected to the top of the 8-hole layered plate, a 32-hole air outlet plate fixedly connected to the top of the 12-hole layered plate, a middle insulation layer fixedly connected to the top of the 32-hole air outlet plate, and an upper cover fixedly connected to the top of the middle insulation layer.

[0008] The air inlet plate has an air inlet at the bottom, the 8-hole layered plate has 8 evenly distributed through holes, the 12-hole layered plate has 16 evenly distributed through holes, and the 32-hole air outlet plate has 32 evenly distributed through holes. Furthermore, the 8-hole layered plate, the 12-hole layered plate, and the 32-hole air outlet plate have pre-reserved flow guide grooves between them. The air inlet of the air inlet plate is connected to the 8 evenly distributed through holes, the 16 evenly distributed through holes, and the 32 evenly distributed through holes in sequence through the flow guide grooves and finally enters the interior of the middle insulation layer.

[0009] Preferably, the flow channel of the 8-hole layered plate includes a cross groove and a circular groove disposed on the bottom surface of the 8-hole layered plate. The cross groove and the circular groove are interconnected. The cross groove and the circular groove are configured to disperse the single airflow from the air intake layer plate into the 8 evenly distributed through holes.

[0010] Preferably, the flow channel of the 12-hole layered plate is a secondary flow channel, which connects the 8 evenly distributed through holes of the 8-hole layered plate with the 16 evenly arranged through holes of the 12-hole layered plate. The 12-hole layered plate is used to split and mix the incoming airflow and divide it into 16 evenly distributed airflow streams.

[0011] Preferably, the guide channel of the 32-hole air outlet plate is a precision guide channel, and the 32 evenly distributed through holes of the 32-hole air outlet plate are densely and evenly distributed in concentric circles on the 32-hole air outlet plate. The 32-hole air outlet plate is constructed to split and equalize the 16 airflows into 32 parallel airflows.

[0012] Preferably, the intermediate insulation layer has a hollow cylindrical structure, and the internal space of the intermediate insulation layer matches the distribution range of the 32 evenly distributed through holes of the 32-hole air outlet plate. The 32 evenly distributed through holes provide vertically upward surrounding airflow to the surface of the vertically placed bar inside the intermediate insulation layer.

[0013] Preferably, the top cover has a conical structure and seals over the top opening of the middle insulation layer. The top cover is designed to limit the airflow range and prevent the airflow inside the middle insulation layer from leaking out.

[0014] Preferably, the air inlet plate, the 8-hole layer plate, the 12-hole layer plate, and the 32-hole outlet plate are fixedly connected by bolts, and a sealing gasket is provided at the connection of each plate.

[0015] Preferably, the air inlet of the air inlet plate is provided with an air inlet connector for connecting to an external hydrogen source, and the air inlet plate is provided with an air inlet channel that guides the airflow from the bottom to the top.

[0016] This utility model has the following beneficial effects: 1. This utility model adopts a multi-level stacked flow distribution structure consisting of an inlet plate, an 8-hole layered plate, a 12-hole layered plate, and a 32-hole outlet plate. By utilizing the pre-set guide grooves between each plate and the progressively increasing through holes, the single airflow at the bottom is precisely split to solve the problems of uneven airflow distribution and contact blind spots on the surface of the bar stock. This achieves the effect of allowing the airflow to flow around the bar stock in all directions without dead angles, thereby significantly improving the efficiency of hydrogen impurity removal.

[0017] 2. This utility model constructs a sealed and uniformly distributed constant-temperature melting environment by setting a 32-hole air outlet plate at the bottom of the middle insulation layer and setting an upper cover on top. The uniform upward airflow field drives the heat in the furnace to carry out uniform heat exchange on the surface of the bar stock. This solves the problem of large temperature gradients and inconsistent grain growth rates in different parts of the bar stock caused by uneven heat transfer in the prior art. It achieves the effect of significantly reducing the temperature difference in different parts of the bar stock and ensuring the uniformity of grain growth, thereby improving the overall quality of the product. Attached Figure Description

[0018] Figure 1 This is a front view of the furnace cavity of a medium-frequency furnace with equally divided air intake, as proposed in this utility model. Figure 2 This is a perspective view of the furnace cavity of a medium-frequency furnace with equally divided air intake, as proposed in this utility model. Figure 3 This is a partial structural diagram of the furnace cavity of a medium-frequency furnace with equal-division air intake proposed in this utility model; Figure 4 This is a partial structural breakdown diagram of the furnace cavity of a medium-frequency furnace with equally divided air intake, as proposed in this utility model. Figure 5 This is a partial exploded view of the furnace cavity of a medium-frequency furnace with equal-division air intake proposed in this utility model.

[0019] Legend: 1. Air inlet plate; 2. 8-hole layered plate; 3. 12-hole layered plate; 4. 32-hole air outlet plate; 5. Middle insulation layer; 6. Top cover. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0021] Example: Please refer to Figures 1 to 5 This utility model provides a medium-frequency furnace cavity with equal gas intake, which aims to solve the structural defects of existing medium-frequency furnace cavities that use single-channel gas intake, such as uneven distribution of hydrogen in the furnace cavity, local gas flow accumulation leading to contact dead corners on the surface of the bar, poor impurity removal effect, and large temperature difference and inconsistent grain growth in different parts of the bar due to uneven gas flow heat transfer.

[0022] Please refer to Figure 1 and Figure 2 The main structure of the intermediate frequency furnace cavity, which features equal-division gas intake, is a longitudinally stacked cylindrical shape. It includes an intake plate 1 at the bottom, an 8-hole layered plate 2 fixedly connected to and positioned on top of the intake plate 1, a 12-hole layered plate 3 fixedly connected to and positioned on top of the 8-hole layered plate 2, a 32-hole outlet plate 4 fixedly connected to and positioned on top of the 12-hole layered plate 3, a middle insulation layer 5 fixedly connected to and positioned on top of the 32-hole outlet plate 4, and a top cover 6 fixedly connected to and positioned on top of the middle insulation layer 5. The intake plate 1, the 8-hole layered plate 2, the 12-hole layered plate 3, and the 32-hole outlet plate 4 are sequentially and tightly fitted together with their central axes coinciding, forming a multi-stage gas diversion base system at the bottom of the furnace cavity. This system is achieved through a layered, stacked internal channel structure. The gas channel is gradually dispersed and homogenized from a single stream. The inlet plate 1 serves as the supporting base and gas source inlet of the entire distribution system. The 8-hole layer plate 2, the 12-hole layer plate 3, and the 32-hole outlet plate 4 sequentially perform the functions of primary dispersion, secondary splitting and mixing, and tertiary homogenization and outlet of the airflow. The middle insulation layer 5 is fixedly installed above the top layer distribution plate, i.e., the 32-hole outlet plate 4, as the core working area. It is used to contain the bar stock to be processed and provide a constant temperature melting environment. The top cover 6 serves as the top sealing component to prevent leakage of internal high-temperature gas. In order to ensure the stability and airtightness of the overall structure, the inlet plate 1, the 8-hole layer plate 2, the 12-hole layer plate 3, and the 32-hole outlet plate 4 are fastened together by bolts passing through the pre-reserved mounting holes on the edges of each plate. Sealing gaskets are also sandwiched between the connecting contact surfaces of each plate to prevent high-pressure hydrogen from escaping from the gaps between the layers.

[0023] Please refer to Figure 3 , Figure 4 and Figure 5 An air inlet connector for connecting to an external hydrogen source is provided at the center of the bottom end of the air inlet plate 1. A vertically upward air inlet channel is provided inside the air inlet plate 1. The air inlet channel vertically guides the single airflow from the bottom to the center area of ​​the top surface of the air inlet plate 1, providing an initial air source for the subsequent diversion process. An 8-hole layered plate 2 fixed to the top of the air inlet plate 1 has a first-stage guide groove of a specific shape on its bottom surface. The first-stage guide groove is specifically composed of a circular groove with the center of the bottom surface of the 8-hole layered plate 2 as the center and a cross groove passing through the center, which are interconnected. The intersection center of the cross groove is accurately aligned with the outlet of the air inlet channel of the air inlet plate 1. The 8-hole layered plate 2 also has 8 through holes evenly distributed along the circumference. The positions of these 8 through holes correspond to the end of the first-stage guide groove or a specific node, so that the single airflow from the air inlet plate 1 is forced to disperse in all directions after entering the cross groove and the circular groove and is guided into the 8 through holes respectively, completing the initial equal division of the airflow from a single stream to 8 streams.

[0024] Meanwhile, the 12-hole layered plate 3, located above the 8-hole layered plate 2, although named as shown in the diagram, actually has 16 evenly arranged through holes in its actual structure to meet the fluid dynamics logic of double flow splitting. The bottom surface of the 12-hole layered plate 3 is provided with a second-stage flow guide channel. The inlet end of the second-stage flow guide channel is connected to the outlet of each of the 8 through holes on the top surface of the 8-hole layered plate 2. The flow channel shape of the second-stage flow guide channel is designed as a branch structure, which can further split, mix, and guide each stream of airflow from the 8-hole layered plate 2 into the 16 through holes on the 12-hole layered plate 3. The 16 through holes are arranged in a circumferential array on the 12-hole layered plate 3, realizing the double flow splitting of airflow from 8 streams to 16 streams. The process involves further multiplication and homogenization. The topmost diversion component, the 32-hole air outlet plate 4, has a more refined third-stage guide channel, or precision guide channel, on its bottom surface. This third-stage guide channel further diverts the 16 airflow streams from the 12-hole layer plate 3. The 32-hole air outlet plate 4 has 32 through holes densely and evenly distributed on its surface in a concentric circle. The third-stage guide channel precisely guides and distributes the 16 airflow streams into these 32 through holes, ultimately forming 32 parallel airflow streams with consistent flow rates, uniform velocity, and vertical upward direction on the top surface of the 32-hole air outlet plate 4. This completes the entire process of transformation from single-stream air intake to 32 uniformly discharged airflow streams.

[0025] As a further refinement of the multi-stage flow distribution structure, to achieve precise first-stage airflow dispersion, the first-stage guide channel on the bottom surface of the 8-hole layered plate 2 is specifically constructed as a composite channel structure with interconnected cross grooves and circular grooves. The center of the cross groove is perpendicularly aligned with the outlet of the air inlet channel of the air inlet layer plate 1, and the circular grooves concentrically surround the cross grooves. The eight through holes on the 8-hole layered plate 2 are evenly distributed along the path of the circular grooves. This structure allows a single stream of high-pressure hydrogen gas to rapidly diffuse in four directions using the cross grooves and then enter the circular grooves to achieve circumferential uniform distribution, before being vertically discharged through the eight through holes. To achieve second-stage flow expansion and mixing, the second-stage guide channel on the bottom surface of the 12-hole layered plate 3... The channel structure is a branched flow guiding network. The 16 through holes on the 12-hole layered plate 3 are arranged in a circular array on the plate body. The branched flow guiding network guides the 8 airflows from the 8-hole layered plate 2 to the inlet of the 16 through holes respectively. During this process, the airflows collide and mix, further eliminating local velocity differences. In order to achieve the final homogenized output, the 32 through holes on the 32-hole outlet plate 4 are densely distributed in multiple concentric circles on the plate body. The precise guide channel on the bottom surface of the 32-hole outlet plate 4, together with the distribution pattern, further subdivides the 16 airflows, ensuring that the gas flowing out of the 32 through holes maintains a high degree of consistency in flow rate and velocity.

[0026] As a preferred embodiment for constructing the working environment and overall sealing of the furnace cavity, in order to ensure that the airflow can fully cover the bar stock to be processed, the middle insulation layer 5 is constructed as a hollow cylindrical structure. The diameter of the cylindrical space inside the middle insulation layer 5 matches the concentric circular distribution range of the 32 through holes on the 32-hole air outlet plate 4, so that the 32 parallel airflows can closely adhere to the inner wall of the middle insulation layer 5 and flow upward around the surface of the bar stock placed vertically in the center, thereby eliminating contact dead corners. In order to prevent high-temperature hydrogen leakage and maintain the pressure inside the furnace, the top cover 6 is constructed as a conical cover. The bottom edge of the top cover 6 is tightly sealed to the top opening edge of the middle insulation layer 5. To ensure the stability and airtightness of the connection of each layer assembly, corresponding mounting holes are provided at the edges of the air inlet layer 1, the 8-hole layer 2, the 12-hole layer 3, and the 32-hole air outlet layer 4. Bolts pass through these mounting holes to press and fix each layer. High-temperature resistant sealing gaskets are provided between the contact surfaces of adjacent layers. A standard air inlet connector is also machined at the bottom of the air inlet layer 1. The air inlet connector is used to make threaded or flanged connections with the external hydrogen supply pipeline.

[0027] Working principle: Hydrogen gas enters through the inlet connector at the bottom of the inlet plate 1. The gas flow then flows vertically upwards along the internal channels of the inlet plate 1, directly into the first gas distribution structure, namely the 8-hole layered plate 2. With the help of the pre-set cross and circular grooves on the bottom surface of the 8-hole layered plate 2, the single-stream concentrated hydrogen gas is quickly dispersed into eight evenly distributed through-holes, completing the first flow division. The gas flow changes from a single concentrated stream to eight initially dispersed streams. Subsequently, the eight streams of gas dispersed by the 8-hole layered plate 2 are smoothly introduced into the top-fixed 12-hole layered plate 3 through the pre-reserved guide channels between layers. The 12-hole layered plate 3 then... The secondary guide and the uniform arrangement of 16 through holes further split and mix the 8 airflows, ultimately dividing them into 16 airflows. This improves the dispersion and optimizes the uniformity of the airflow distribution, preventing local airflow aggregation. The 16 airflows then enter the 32-hole air outlet plate 4, which is fixedly connected at the top. As the final diversion and air outlet layer, the 32-hole air outlet plate 4 completely splits and homogenizes the 16 airflows through the precise guidance of the channel and the 32 dense and uniformly distributed through holes, ultimately forming 32 parallel airflows with consistent flow and uniform distribution, completing the conversion from a single stream to 32 streams. A uniform airflow is introduced into the insulation layer. After being divided into 32 equal streams by a 32-hole gas outlet plate, the airflow is vertically and uniformly introduced into the interior of the middle insulation layer 5. The middle insulation layer 5 provides a constant temperature melting environment for the bar stock. The top cover 6, which is fixedly connected to the top of the middle insulation layer 5, acts as a seal to prevent the internal airflow from leaking out. At the same time, the internal space is precisely matched with the distribution range of the 32 airflows to ensure that the airflow can cover the entire insulation layer area. The bar stock is placed vertically in the middle insulation layer 5. The 32 uniform airflows flow around the surface of the bar stock from different directions. Compared with the traditional single-channel airflow that is concentrated in the middle of the furnace cavity, this working mode allows all areas of the bar stock surface to fully contact hydrogen, avoiding the problem of local non-contact with gas, significantly improving the impurity removal effect. At the same time, the uniform airflow drives the rapid heat transfer in the furnace, which greatly reduces the temperature difference of all parts of the bar stock, keeps the grain growth rate consistent, and fundamentally improves the grain uniformity.

Claims

1. A medium-frequency furnace cavity with equally spaced air intake, comprising: Air inlet plate (1), 8-hole layer plate (2) fixedly connected to the top of the air inlet plate (1), 12-hole layer plate (3) fixedly connected to the top of the 8-hole layer plate (2), 32-hole air outlet plate (4) fixedly connected to the top of the 12-hole layer plate (3), middle insulation layer (5) fixedly connected to the top of the 32-hole air outlet plate (4), and top cover (6) fixedly connected to the top of the middle insulation layer (5); Its features are, The air inlet plate (1) has an air inlet at its bottom end. The 8-hole layered plate (2) has 8 evenly distributed through holes. The 12-hole layered plate (3) has 16 evenly arranged through holes. The 32-hole air outlet plate (4) has 32 evenly distributed through holes. A guide groove is reserved between the layers of the 8-hole layered plate (2), the 12-hole layered plate (3), and the 32-hole air outlet plate (4). The air inlet of the air inlet plate (1) is connected to the 8 evenly distributed through holes, the 16 evenly arranged through holes, and the 32 evenly distributed through holes in sequence through the guide groove and finally enters the interior of the middle insulation layer (5).

2. The medium-frequency furnace cavity with equal air intake as described in claim 1, characterized in that, The flow channel of the 8-hole layered plate (2) includes a cross groove and a circular groove disposed on the bottom surface of the 8-hole layered plate (2).

3. The medium-frequency furnace cavity with equal air intake as described in claim 1, characterized in that, The flow channel of the 12-hole layered plate (3) is a secondary flow channel, which connects the 8 evenly distributed through holes of the 8-hole layered plate (2) with the 16 evenly arranged through holes of the 12-hole layered plate (3).

4. The medium-frequency furnace cavity with equal air intake as described in claim 1, characterized in that, The guide groove of the 32-hole air outlet plate (4) is a precision guide channel. The 32 uniformly distributed through holes of the 32-hole air outlet plate (4) are densely and uniformly distributed in concentric circles on the 32-hole air outlet plate (4). The 32-hole air outlet plate (4) is constructed to split and equalize 16 airflows into 32 parallel airflows.

5. The medium-frequency furnace cavity with equal air intake according to claim 1, characterized in that, The intermediate insulation layer (5) has a hollow cylindrical structure. The internal space of the intermediate insulation layer (5) matches the distribution range of the 32 uniformly distributed through holes of the 32-hole air outlet plate (4). The 32 uniformly distributed through holes are designed to provide vertically upward surrounding airflow to the surface of the vertically placed bar inside the intermediate insulation layer (5).

6. The medium-frequency furnace cavity with equal air intake as described in claim 1, characterized in that, The top cover (6) has a conical structure and seals the top opening of the middle insulation layer (5). The top cover (6) is constructed to limit the airflow range and prevent the airflow inside the middle insulation layer (5) from being exposed.

7. The medium-frequency furnace cavity with equal air intake according to claim 1, characterized in that, The air inlet plate (1), the 8-hole layer plate (2), the 12-hole layer plate (3), and the 32-hole outlet plate (4) are fixedly connected by bolts.

8. The medium-frequency furnace cavity with equal air intake according to claim 1, characterized in that, The air inlet of the air inlet plate (1) is provided with an air inlet connector for connecting to an external hydrogen source.

Images