A gas supply device for heating a kiln

Abstract

This utility model relates to the field of industrial kiln technology, and provides a gas supply device for kiln heating. The device includes an air supply and delivery branch, a nitrogen supply and delivery branch, a natural gas supply and delivery branch, a natural gas input branch, and a gas transmission branch for connection to the kiln. The air supply and delivery branch, nitrogen supply and delivery branch, and natural gas input branch are respectively connected to the gas transmission branch. An orifice plate flow meter is installed in the nitrogen supply and delivery branch. The natural gas supply and delivery branch is sequentially equipped with a flow regulator and a proportional valve. The natural gas supply and delivery branch is connected to the natural gas input branch through the proportional valve, and the flow regulator is connected to the orifice plate flow meter through a signal line. This device can flexibly switch the gas medium according to the type of metal thermoforming. Furthermore, for uncoated bare plates, a pure nitrogen protective atmosphere or a mixed protective atmosphere containing nitrogen can be selected, which can significantly reduce nitrogen consumption and thus reduce production costs.

Description

Technical Field

[0001] This utility model relates to the field of industrial kiln technology, and more specifically, to a gas supply device for kiln heating. Background Technology

[0002] In the field of metal hot forming, the roller hearth furnace, as the core equipment for austenitizing heating of steel plates, directly determines the surface quality and mechanical properties of the steel plates after heat treatment through its internal atmosphere control. For the hot forming process of bare plates without coating protection, in order to prevent oxidation reactions of steel plates at high temperatures, it is currently common practice to continuously introduce a large amount of nitrogen into the furnace to create a protective atmosphere, thereby achieving oxidation protection by replacing air and isolating oxygen.

[0003] However, nitrogen is expensive to use, and the amount of nitrogen required to maintain an effective protective atmosphere in large-scale continuous production is enormous, resulting in high production costs. At the same time, most existing gas supply devices in roller hearth furnace atmosphere stations can only regulate the flow and pressure of nitrogen, which cannot meet the needs of precise mixing of multiple gases, nor can they reduce nitrogen consumption by optimizing the gas composition.

[0004] In addition, there are process differences in the hot forming of different metals in actual production. The existing gas supply device is difficult to switch the gas medium flexibly according to the type of hot forming of metal, so it is difficult to meet the production requirements of efficient, energy-saving and safe hot forming roller hearth furnace. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings and deficiencies in the existing technology and provide a gas supply device for kiln heating. This gas supply device can flexibly switch the gas medium according to the type of metal hot forming. In addition, for uncoated bare plates, a pure nitrogen protective atmosphere or a mixed protective atmosphere containing nitrogen can be selected to be introduced, which can significantly reduce nitrogen consumption, thereby reducing production costs and breaking the limitations of the current single nitrogen protection method.

[0006] To achieve the above objectives, this utility model is implemented through the following technical solution: a gas supply device for kiln heating, comprising an air supply and delivery branch, a nitrogen supply and delivery branch, a natural gas supply and delivery branch, a natural gas input branch, and a gas transmission branch for connection with the kiln; the air supply and delivery branch, the nitrogen supply and delivery branch, and the natural gas input branch are respectively connected to the gas transmission branch; the nitrogen supply and delivery branch is equipped with an orifice plate flow meter; the natural gas supply and delivery branch is sequentially equipped with a flow regulator and a proportional valve, the natural gas supply and delivery branch is connected to the natural gas input branch through the proportional valve, the flow regulator is connected to the orifice plate flow meter through a signal line, and the opening of the proportional valve is adjusted by detecting the actual flow rate of nitrogen, so that natural gas and nitrogen are delivered to the gas transmission branch according to a set mixing ratio.

[0007] Along the air supply and delivery branch from the inlet to the outlet, the air supply and delivery branch is sequentially equipped with an air ball valve, an air pressure reducing valve, and an air solenoid valve.

[0008] An air pressure switch, an air pressure gauge protection valve, and an air pressure gauge are sequentially installed between the air pressure reducing valve and the air solenoid valve; an air pressure gauge is installed between the air ball valve and the air pressure reducing valve.

[0009] Along the nitrogen supply and delivery branch from the inlet to the outlet, the nitrogen supply and delivery branch is sequentially equipped with a nitrogen balloon valve, a nitrogen pressure reducing valve, and a nitrogen solenoid valve. An orifice plate flow meter is installed at the rear of the nitrogen solenoid valve.

[0010] A nitrogen pressure switch, a nitrogen pressure gauge protection valve, and a nitrogen pressure gauge are sequentially installed between the nitrogen pressure reducing valve and the nitrogen solenoid valve; a nitrogen pressure gauge is installed between the nitrogen balloon valve and the nitrogen pressure reducing valve.

[0011] The natural gas supply and transmission branch includes a main branch, a branch line one for mixing with nitrogen, and a branch line two for heating the kiln; one end of the branch line one is connected to the main branch and the other end is connected to the natural gas input branch; one end of the branch line two is connected to the main branch and the other end is used to connect to the natural gas burner in the kiln.

[0012] Along the natural gas supply direction, the main branch line is sequentially equipped with a natural gas ball valve, a filter, a natural gas pressure regulating valve, a natural gas safety solenoid valve, and a smart gas turbine flow meter; between the natural gas pressure regulating valve and the natural gas safety solenoid valve, and between the natural gas safety solenoid valve and the smart gas turbine flow meter, a natural gas pressure switch and a natural gas pressure gauge are respectively installed.

[0013] The flow regulator and proportional valve are installed on branch line one; along the natural gas supply direction, branch line one is also sequentially equipped with natural gas ball valve two, natural gas solenoid valve and float flow meter, with the flow regulator and proportional valve sequentially installed at the rear of the float flow meter.

[0014] Along the gas transmission direction, the gas transmission branch is equipped with a regulating butterfly valve, a pressure gauge and a flow meter in sequence.

[0015] The gas supply device also includes a nitrogen cooling delivery branch for cooling kiln components; the nitrogen cooling delivery branch is connected to the nitrogen supply delivery branch and the gas delivery branch respectively, and is equipped with a nitrogen solenoid valve and a manual flow stop valve.

[0016] In the above scheme, this utility model can flexibly switch the gas medium according to the type of metal hot forming (steel plate type): for steel plates with coating protection processed in the kiln, dry air can be introduced into the kiln through the air supply and conveying branch to meet the heat treatment requirements; for steel plates without coating processed in the kiln, pure nitrogen protective atmosphere can be introduced into the kiln through the nitrogen supply and conveying branch, or a mixed protective atmosphere of nitrogen and natural gas can be introduced into the kiln according to the set mixing ratio of natural gas and nitrogen. In practical application, the kiln temperature threshold can be set to 750℃. When the kiln heating temperature exceeds 750℃, the supply of protective atmosphere mixed with natural gas is activated; when the kiln temperature is below 750℃, the natural gas supply is cut off, and only pure nitrogen is used as the protective atmosphere, thus eliminating the safety hazards caused by the accumulation of natural gas at low temperatures from the source and further improving the operational safety of the device.

[0017] This invention utilizes a mixture of nitrogen and natural gas as a protective atmosphere. The natural gas reacts with oxygen within the furnace, consuming it and partially replacing the protective effect of nitrogen, fundamentally reducing nitrogen usage and overcoming the limitations of existing single-nitrogen protection methods. The mixing ratio of natural gas is controlled within an extremely low range to ensure its safe operation within the kiln, serving only to consume oxygen without producing additional harmful byproducts. When using a nitrogen-natural gas mixture as the protective atmosphere, this invention dynamically adjusts the proportional valve opening based on a preset mixing ratio, using a flow regulator to measure the nitrogen flow rate in real time. This allows the natural gas flow rate to automatically and synchronously adjust with the nitrogen flow rate, maintaining the preset mixing ratio without manual adjustment of the natural gas flow rate. This achieves precise matching of the two gas flow rates, ensuring the mixing error is controlled within acceptable limits. This ensures a stable delivery of the mixed protective atmosphere into the kiln, adapting to the atmosphere requirements of different kiln operating conditions and preventing pressure and flow fluctuations from affecting the protective effect.

[0018] In addition, the gas supply device of this utility model can also heat the kiln by outputting natural gas through branch line two, and cool the kiln components through nitrogen cooling delivery branch line.

[0019] Compared with the prior art, the present invention has the following advantages and beneficial effects: the gas supply device for kiln heating of the present invention can flexibly switch the gas medium according to the metal hot forming type. In addition, for uncoated bare plates, pure nitrogen protective atmosphere or mixed protective atmosphere containing nitrogen can be selected to be introduced, which can significantly reduce nitrogen consumption, thereby reducing production costs and breaking the limitations of the current single nitrogen protection method. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the gas supply device for kiln heating according to this utility model; Figure 2This is a partial schematic diagram of the gas supply device of this utility model; Figure 3 This is a schematic diagram of the natural gas supply and transmission branch in the gas supply device of this utility model; Among them, 1 is the air supply and delivery branch, 1.1 is the air inlet, 2 is the nitrogen supply and delivery branch, 2.1 is the nitrogen inlet, 3 is the natural gas supply and delivery branch, 3.1 is the main branch, 3.2 is branch line one, 3.3 is branch line two, 4 is the natural gas input branch, 5 is the gas transmission branch, 5.1 is the output end, 6 is the orifice plate flow meter, 7 is the flow regulator, 8 is the proportional valve, 9 is the signal line, 10 is the air ball valve, 11 is the air pressure reducing valve, 12 is the air solenoid valve, 13 is the air pressure switch, 14 is the air pressure gauge protection valve, 15 is the air pressure gauge one, 16 is the air pressure gauge two, 17 is the nitrogen ball valve, and 18 is the nitrogen... 19 is a nitrogen pressure reducing valve; 20 is a nitrogen pressure switch; 21 is a nitrogen pressure gauge protection valve; 22 is a nitrogen pressure gauge; 23 is a nitrogen pressure gauge; 24 is a natural gas ball valve; 25 is a filter; 26 is a natural gas pressure regulating valve; 27 is a natural gas safety solenoid valve; 28 is an intelligent gas turbine flow meter; 29 is a natural gas pressure switch; 30 is a natural gas pressure gauge; 31 is a natural gas ball valve; 32 is a natural gas solenoid valve; 33 is a float flow meter; 34 is a nitrogen cooling delivery branch; 35 is a nitrogen solenoid valve; 36 is a manual flow control plug valve; 37 is a regulating butterfly valve; 38 is a pressure gauge; and 39 is a flow meter. Detailed Implementation

[0021] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0022] Example

[0023] like Figures 1 to 3 As shown, the gas supply device for kiln heating of this utility model includes an air supply and delivery branch 1, a nitrogen supply and delivery branch 2, a natural gas supply and delivery branch 3, a natural gas input branch 4, and a gas transmission branch 5 for connection to the kiln. The air supply and delivery branch 1, nitrogen supply and delivery branch 2, and natural gas supply and delivery branch 3 are respectively connected to the gas transmission branch 5. The nitrogen supply and delivery branch 2 is equipped with an orifice plate flow meter 6. The natural gas supply and delivery branch 3 is sequentially equipped with a flow regulator 7 and a proportional valve 8. The natural gas supply and delivery branch 3 is connected to the natural gas input branch 4 through the proportional valve 8. The flow regulator 7 is connected to the orifice plate flow meter 6 through a signal line 9. By detecting the actual flow rate of nitrogen, the opening of the proportional valve 8 is adjusted, so that natural gas and nitrogen are delivered to the gas transmission branch 5 according to a set mixing ratio.

[0024] Specifically, along the air supply and delivery branch 1 from the air inlet 1.1 to the air outlet, the air supply and delivery branch 1 is sequentially equipped with an air ball valve 10, an air pressure reducing valve 11, and an air solenoid valve 12. Between the air pressure reducing valve 11 and the air solenoid valve 12, an air pressure switch 13, an air pressure gauge protection valve 14, and an air pressure gauge 15 are sequentially installed; between the air ball valve 10 and the air pressure reducing valve 11, an air pressure gauge 16 is installed.

[0025] Along the nitrogen supply and delivery branch 2 from the nitrogen inlet 2.1 to the nitrogen outlet, the nitrogen supply and delivery branch 2 is sequentially equipped with a nitrogen balloon valve 17, a nitrogen pressure reducing valve 18, and a nitrogen solenoid valve 19. An orifice flow meter 6 is located behind the nitrogen solenoid valve 19. Between the nitrogen pressure reducing valve 18 and the nitrogen solenoid valve 19, a nitrogen pressure switch 20, a nitrogen pressure gauge protection valve 21, and a nitrogen pressure gauge 22 are sequentially installed; between the nitrogen balloon valve 17 and the nitrogen pressure reducing valve 18, a nitrogen pressure gauge 23 is installed.

[0026] The natural gas supply and transmission branch 3 of this utility model includes a main branch 3.1, a first branch 3.2 for mixing with nitrogen, and a second branch 3.3 for heating the kiln. One end of the first branch 3.2 is connected to the main branch 3.1, and the other end is connected to the natural gas input branch 4. One end of the second branch 3.3 is connected to the main branch 3.1, and the other end is used to connect to the natural gas burner in the kiln.

[0027] Specifically, along the natural gas supply direction, the main branch line 3.1 is sequentially equipped with a natural gas ball valve 24, a filter 25, a natural gas pressure regulating valve 26, a natural gas safety solenoid valve 27, and a smart gas turbine flow meter 28. Additionally, a natural gas pressure switch 29 and a natural gas pressure gauge 30 are sequentially installed between the natural gas pressure regulating valve 26 and the natural gas safety solenoid valve 27, and between the natural gas safety solenoid valve 27 and the smart gas turbine flow meter 28, respectively.

[0028] Along the natural gas supply direction, this branch line 3.2 is also equipped with a natural gas ball valve 31, a natural gas solenoid valve 32, and a float flow meter 33 in sequence. The flow regulator 7 and the proportional valve 8 are both installed on the branch line 3.2 and are installed in sequence behind the float flow meter 33.

[0029] Along the gas transmission direction, the gas transmission branch 5 is sequentially equipped with a regulating butterfly valve 37, a pressure gauge 38 and a flow meter 39, and the output end 5.1 of the gas transmission branch 5 is connected to the kiln.

[0030] The gas supply device also includes a nitrogen cooling delivery branch 34 for cooling kiln components. This nitrogen cooling delivery branch 34 is connected to the nitrogen supply delivery branch 2 and the gas delivery branch 5, and is equipped with a nitrogen solenoid valve 35 and a manual flow control valve 36. When kiln components, such as the support bearings of the kiln rollers, require cooling due to high operating temperatures, gas cooling can be achieved through this nitrogen cooling delivery branch 34.

[0031] This invention allows for flexible switching of the gas medium based on the type of metal hot forming (steel plate type): for steel plates with protective coatings processed in the kiln, dry air can be introduced into the kiln via air supply and conveying branch 1 to meet heat treatment requirements; for steel plates without coatings processed in the kiln, a pure nitrogen protective atmosphere can be introduced into the kiln via nitrogen supply and conveying branch 2, or a mixed protective atmosphere of nitrogen and natural gas can be introduced into the kiln according to a set mixing ratio of natural gas and nitrogen. In practical applications, the kiln temperature threshold can be set to 750℃. When the kiln heating temperature exceeds 750℃, the supply of the protective atmosphere mixed with natural gas is activated; when the kiln temperature is below 750℃, the natural gas supply is cut off, and only pure nitrogen is used as the protective atmosphere, eliminating the safety hazards caused by the accumulation of natural gas at low temperatures from the source and further improving the operational safety of the device.

[0032] This invention utilizes a mixture of nitrogen and natural gas as a protective atmosphere. The natural gas reacts with oxygen within the furnace, consuming oxygen and partially replacing the protective effect of nitrogen, fundamentally reducing nitrogen usage and overcoming the limitations of existing single-nitrogen protection methods. The mixing ratio of natural gas is controlled within an extremely low range to ensure its safe operation within the kiln, serving only to consume oxygen without producing additional harmful byproducts. When using a nitrogen-natural gas mixture as the protective atmosphere, this invention dynamically adjusts the opening of the proportional valve 8 based on the preset mixing ratio of natural gas and nitrogen, using a flow regulator 7 to measure the nitrogen flow rate in real time. This allows the natural gas flow rate to automatically and synchronously adjust with the nitrogen flow rate, maintaining the preset mixing ratio without requiring manual adjustment of the natural gas flow rate. This achieves precise matching of the two gas flow rates, ensuring that the mixing error is controlled within acceptable limits. This ensures a stable delivery of the mixed protective atmosphere into the kiln, adapting to the atmosphere requirements of different kiln operating conditions and preventing pressure and flow fluctuations from affecting the protective effect.

[0033] In addition, the gas supply device of this utility model can also output natural gas to heat the kiln through branch line 2 3.3, and cool the kiln components through nitrogen cooling delivery branch line 34.

[0034] The above embodiments are preferred embodiments of the present utility model, but the embodiments of the present utility model are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present utility model shall be considered equivalent substitutions and shall be included within the protection scope of the present utility model.

Claims

1. A gas supply device for a kiln heater, characterized by: It includes an air supply and delivery branch, a nitrogen supply and delivery branch, a natural gas supply and delivery branch, a natural gas input branch, and a gas transmission branch for connection to the kiln; the air supply and delivery branch, nitrogen supply and delivery branch, and natural gas input branch are respectively connected to the gas transmission branch; the nitrogen supply and delivery branch is equipped with an orifice plate flow meter; the natural gas supply and delivery branch is sequentially equipped with a flow regulator and a proportional valve, the natural gas supply and delivery branch is connected to the natural gas input branch through the proportional valve, and the flow regulator is connected to the orifice plate flow meter through a signal line. By detecting the actual flow rate of nitrogen, the opening of the proportional valve is adjusted so that natural gas and nitrogen are delivered to the gas transmission branch according to a set mixing ratio.

2. The furnace heated gas supply apparatus of claim 1, wherein: Along the air supply and delivery branch from the inlet to the outlet, the air supply and delivery branch is sequentially equipped with an air ball valve, an air pressure reducing valve, and an air solenoid valve.

3. The gas supply device for kiln heating according to claim 2, characterized in that: An air pressure switch, an air pressure gauge protection valve, and an air pressure gauge are sequentially installed between the air pressure reducing valve and the air solenoid valve; an air pressure gauge is installed between the air ball valve and the air pressure reducing valve.

4. The gas supply device for kiln heating according to claim 1, characterized in that: Along the nitrogen supply and delivery branch from the inlet to the outlet, the nitrogen supply and delivery branch is sequentially equipped with a nitrogen balloon valve, a nitrogen pressure reducing valve, and a nitrogen solenoid valve. An orifice plate flow meter is installed at the rear of the nitrogen solenoid valve.

5. The gas supply device for kiln heating according to claim 4, characterized in that: A nitrogen pressure switch, a nitrogen pressure gauge protection valve, and a nitrogen pressure gauge are sequentially installed between the nitrogen pressure reducing valve and the nitrogen solenoid valve; a nitrogen pressure gauge is installed between the nitrogen balloon valve and the nitrogen pressure reducing valve.

6. The gas supply device for kiln heating according to claim 1, characterized in that: The natural gas supply and transmission branch includes a main branch, a branch line one for mixing with nitrogen, and a branch line two for heating the kiln; one end of the branch line one is connected to the main branch and the other end is connected to the natural gas input branch; one end of the branch line two is connected to the main branch and the other end is used to connect to the natural gas burner in the kiln.

7. The gas supply device for kiln heating according to claim 6, characterized in that: Along the natural gas supply direction, the main branch line is sequentially equipped with a natural gas ball valve, a filter, a natural gas pressure regulating valve, a natural gas safety solenoid valve, and a smart gas turbine flow meter; between the natural gas pressure regulating valve and the natural gas safety solenoid valve, and between the natural gas safety solenoid valve and the smart gas turbine flow meter, a natural gas pressure switch and a natural gas pressure gauge are respectively installed.

8. The gas supply device for kiln heating according to claim 6, characterized in that: The flow regulator and proportional valve are installed on branch line one; along the natural gas supply direction, branch line one is also sequentially equipped with natural gas ball valve two, natural gas solenoid valve and float flow meter, with the flow regulator and proportional valve sequentially installed at the rear of the float flow meter.

9. The gas supply device for kiln heating according to claim 1, characterized in that: Along the gas transmission direction, the gas transmission branch is equipped with a regulating butterfly valve, a pressure gauge and a flow meter in sequence.

10. The gas supply device for kiln heating according to claim 1, characterized in that: The gas supply device also includes a nitrogen cooling delivery branch for cooling kiln components; the nitrogen cooling delivery branch is connected to the nitrogen supply delivery branch and the gas delivery branch respectively, and is equipped with a nitrogen solenoid valve and a manual flow stop valve.

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