JP2016056428A - Heating device and heating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heating device which can be of a reduced size while suppressing oxidation of a material to be heated and in which a heat loss is reduced, as well as a heating method.SOLUTION: A heating device 1 has: a tubular flame burner 10 configured so that an oxidizer and fuel are jetted from a slit 12, which is opened in the wall surface of a cylindrical combustion chamber 11 along the axial direction, toward the tangential direction of the combustion chamber 11 and the fuel is burned spirally; a material supply portion for supplying a linear or bar-shaped material M to be heated to the central part, in the radial direction, of the combustion chamber 11 along the axial direction; and supply quantity control means 20 for controlling the amount of oxidizer to be supplied to the combustion chamber 11 so that an equivalent ratio in the combustion chamber 11 is greater than 1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a heating apparatus and a heating method for heating a linear or rod-shaped material to be heated.

  Conventionally, in the manufacturing process of linear or rod-like metal materials such as steel wires and pipes, heat treatment has been applied to metal materials in order to homogenize the metal structure, remove work hardening, carburizing treatment, annealing, etc. Is done. At that time, in order to prevent oxidation of the metal material, heating is performed in a vacuum or in a reducing atmosphere.

  In the continuous vacuum carburizing apparatus of Patent Document 1, a plurality of core tubes and electric heaters are disposed in a vacuum chamber, and a carburizing gas is supplied to the first core tube and an inert gas is supplied to the second core tube. In a state where the first core tube is heated to 1000 ° C., for example, the metal wire is inserted into the first core tube and the second core tube. Then, the carburizing process proceeds in the first core tube, and the diffusion of carbon proceeds in the second core tube. Since the process is performed in vacuum, surface carburization and grain boundary oxidation can be suppressed and good carburization is possible.

  In the heat treatment apparatus of Patent Document 2, heating means such as a burner is provided below the pipe, and a reducing gas such as hydrogen or an inert gas such as nitrogen is supplied into the pipe. Then, for example, the metal wire traveling in the pipe is heated in a range of 700 ° C. to 1150 ° C., and heat treatment such as bright annealing is performed.

  On the other hand, an industrial furnace such as a crucible furnace is used for melting aluminum and zinc. In Patent Document 3, a melting chamber for melting a metal material by a melting burner, a holding chamber for adjusting and holding a molten metal flowing from the melting chamber to a predetermined temperature by a holding burner, and a solution communicating with the holding chamber are added to the casting machine. A melting and holding furnace constituted by a drawing chamber is disclosed.

JP 2005-248295 A JP 2008-133506 A JP 2005-76972 A

  The above-described heat treatment apparatus has many problems in terms of cost and energy efficiency. That is, in the continuous vacuum carburizing apparatus of Patent Document 1, a furnace core tube and an electric heater are installed in a vacuum chamber in order to avoid oxidation of the metal wire, and an inert gas is supplied as an atmosphere gas to the furnace core tube. Increased complexity and cost of atmospheric gas supply are problems. Moreover, since heat conduction by convection cannot be expected in vacuum heat treatment, it is disadvantageous in terms of heat transfer. The same applies to the heat treatment apparatus of Patent Document 2. In the melting and holding furnace of Patent Document 3, aluminum is melted by heating with a complete combustion gas from a burner, and since it is held in a molten state, an oxide film is generated on the surface of the molten metal, and material loss occurs. There is a risk that a product created using molten metal will be defective. Furthermore, common to these industrial furnaces, heat storage loss due to the heat capacity is large, and since the area of the outer surface of the furnace is large, the heat dissipation loss proportional to the surface area is also large.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a heating apparatus and a heating method capable of reducing the size and suppressing heat loss in the apparatus while suppressing oxidation of the material to be heated. There is in point to do.

  In order to achieve the above object, the heating apparatus according to the present invention is characterized in that an oxidizing agent is formed from a slit that opens in the axial direction on a wall surface of a cylindrical combustion chamber toward a tangential direction of the wall surface of the combustion chamber. Flame burner that is swirled and burned separately or mixed and injected, and a material to be heated linearly or rod-shaped along the axial direction of the combustion chamber at the radial center of the combustion chamber And a supply amount control means for controlling the supply amount of the oxidant to the combustion chamber so that the equivalence ratio becomes larger than 1 in the combustion chamber.

  The characteristic configuration of the heating method according to the present invention for achieving the above object is that an oxidizing agent is provided from a slit that opens along the axial direction to a wall surface of a cylindrical combustion chamber toward a tangential direction of the wall surface of the combustion chamber. And a tubular flame burner that is swirled and burned separately or mixed, and a linear or rod-like covering along the axial direction of the combustion chamber at the center in the radial direction of the combustion chamber. A heating material is supplied, and an oxidizing agent and a fuel are jetted into the combustion chamber so as to have an equivalence ratio greater than 1 in the combustion chamber, and swirl combustion is performed to heat the material to be heated.

From the slit that opens along the axial direction to the wall surface of the cylindrical combustion chamber, and oxidant and fuel are jetted separately or mixed and swirled and burned toward the tangential direction of the wall surface of the combustion chamber, A tubular flame is generated in the combustion chamber. The combustion gas at the center of the tubular flame becomes high because the adiabatic flame temperature is substantially realized, and the material to be heated can be heated in a short time to reach a desired processing temperature and melting temperature. Therefore, the size and surface area of the heating device can be reduced, and heat storage loss and heat dissipation loss in the heating device can be reduced.
In addition, the combustion chamber where the tubular flame is generated is covered with an unburned air-fuel mixture (mixed gas of oxidizer and fuel) at the room temperature (wall surface), so the heat dissipation loss to the outside is extremely small. Depending on the case, the heat insulating material can be reduced or omitted.
That is, by using the tubular flame burner, energy saving and cost saving of the heating device can be realized.

  In addition, since the supply amount of the oxidant to the combustion chamber is controlled so that the equivalence ratio is greater than 1 in the combustion chamber, the combustion in the combustion chamber of the tubular flame burner is a reduction combustion with excess fuel. Since the tubular flame is called a laminar flame, unlike the turbulent flame, an oxidizing atmosphere region is not locally formed in the combustion gas layer at the center of the tubular flame. In addition, the tubular flame is suitable for this application because it has a wider combustion area and can be stably burned in a fuel excess than a general industrial burner. And since a material supply part supplies the to-be-heated material of linear or rod shape to the center part of the radial direction of a combustion chamber along the axial direction of a combustion chamber, heating to a to-be-heated material is carried out without oxidation Is possible.

  That is, according to the above characteristic configuration, the oxidant containing oxygen and the fuel are individually or from the slit that opens in the axial direction on the wall surface of the cylindrical combustion chamber toward the tangential direction of the wall surface of the combustion chamber, or In a tubular flame burner that is swirled by mixing and jetting, an oxidizing agent and fuel are jetted into the combustion chamber so that the equivalence ratio is greater than 1 in the combustion chamber, and swirl combustion is performed, so that the central portion in the radial direction of the combustion chamber In addition, a linear or rod-shaped material to be heated is supplied along the axial direction of the combustion chamber and the material to be heated is heated, so that the size of the heating device can be reduced and the heat dissipation loss and heat storage loss can be reduced. The material can be heated without oxidation.

  Another characteristic configuration of the heating device according to the present invention is that the fuel and oxidant before combustion are present in the combustion chamber in order from the wall surface toward the central axis of the combustion chamber in the radial direction of the combustion chamber. An unburned region, a flame region in which a combustion reaction of fuel proceeds, and a combustion gas region in which reducing combustion gas exists after the completion of the combustion reaction are formed in concentric layers, and the material supply unit is the material to be heated Is supplied to the combustion gas region.

  Another characteristic configuration of the heating method according to the present invention is that the fuel and oxidant before combustion are present in the combustion chamber in order from the wall surface toward the central axis of the combustion chamber in the radial direction of the combustion chamber. An unburned area, a flame area in which fuel burns, and a combustion gas area in which reducing combustion gas generated by burning fuel exists are formed in concentric layers, and the heated material is supplied to the combustion gas area There is in point to do.

  When the oxidizing agent and the fuel are jetted into the combustion chamber of the tubular flame burner so that the equivalence ratio is greater than 1, a tubular flame is generated, and the combustion chamber is radially directed from the wall surface toward the central axis of the combustion chamber. In order, the unburned region where the fuel and oxidant before combustion exist, the flame region where the combustion reaction of the fuel proceeds, and the combustion gas region where the reducing combustion gas exists after the completion of the combustion reaction are concentric layered To occur. There is no fear that an oxidizing atmosphere is locally formed in the combustion gas region in the center of the combustion chamber unlike a turbulent flame with excessive fuel. That is, according to the above characteristic configuration, in the combustion chamber, in the radial direction of the combustion chamber, in order from the wall surface toward the central axis of the combustion chamber, the unburned region where the fuel and the oxidant before combustion exist, and the combustion reaction of the fuel The non-oxidative heating is achieved by creating a concentric layer of a flame region where the combustion proceeds and a combustion gas region where reducing combustion gas exists after the completion of the combustion reaction, and supplying the material to be heated to the combustion gas region. Processing can be performed stably. The tubular flame is suitable for this application because it has a wider combustion region and can be stably burned in a fuel excess than a general industrial burner. That is, in the tubular flame burner, the combustion is stable against fluctuations in the equivalence ratio in the reduction combustion region, and the object to be processed is not locally exposed to the oxidizing atmosphere.

  Another characteristic configuration of the heating device according to the present invention is to have a plurality of stages of the tubular flame burners adjacent in the axial direction, and the supply amount control means selects the tubular flame burner to be operated.

  According to the above-described characteristic configuration, the heating device has a plurality of stages of tubular flame burners adjacent in the axial direction, and the supply amount control means selects the tubular flame burner to be operated, so that the selected tubular flame burner is tubular. A flame is produced and no tubular flame is produced from the unselected tubular flame burner. That is, by selecting the tubular flame burner to be operated, the axial length of the tubular flame to be generated can be changed, and a tubular flame having a length necessary for heating the material to be heated can be formed.

  Another characteristic configuration of the heating device according to the present invention is arranged upstream of the tubular flame burner in the supply direction of the material to be heated, and mixes reducing combustion gas generated in the tubular flame burner with an oxidant. And having a preheating portion for heating and heating the material to be heated.

  The tubular flame burner is supplied with an oxidant and fuel so that the equivalence ratio is greater than 1 in the combustion chamber, so that the combustion gas generated in the tubular flame burner is caused by unburned fuel or incomplete combustion. Contains carbon monoxide and hydrogen. According to the above characteristic configuration, the preheating part is arranged upstream of the tubular flame burner in the supply direction of the material to be heated, and the reducing combustion gas generated in the tubular flame burner is mixed with the oxidant and burned. Since the material to be heated is heated, the material to be heated can be preheated before being heated by the tubular flame burner. Further, since the fuel that has not been burned by the tubular flame burner, that is, the unburned combustible gas, can be used in the preheating section, the energy saving performance of the heating device can be improved. Furthermore, since the combustible fuel and carbon monoxide are removed from the combustion gas (exhaust gas) by the combustion in the preheating portion, the safety of the heating device can be improved.

  Another characteristic configuration of the heating device according to the present invention is that the preheating portion has a cylindrical preheating combustion chamber, and the wall of the preheating combustion chamber is formed from a slit that opens in the axial direction on the wall surface of the preheating combustion chamber. The point is that the oxidizing gas is ejected toward the tangential direction to burn the reducing combustion gas generated in the tubular flame burner.

  According to the above characteristic configuration, the preheating part has the cylindrical preheating combustion chamber, and the oxidant is ejected from the slit opening in the axial direction on the wall surface of the preheating combustion chamber toward the tangential direction of the wall surface of the preheating combustion chamber. Thus, the reducing combustion gas generated in the tubular flame burner is combusted, so that a cylindrical flame is generated in the preheating combustion chamber and the material to be heated can be efficiently heated. If the combustion gas that serves as fuel in the preheating section is supplied from the axial direction to the preheating combustion chamber, the flame generated in the preheating combustion chamber cannot be called a tubular flame in the academic definition, but in that case Even so, a cylindrical flame is generated, and the material to be heated can be heated efficiently.

  Another characteristic configuration of the heating device according to the present invention is that the preheating unit includes a pilot burner that ignites combustion gas generated in the tubular flame burner.

  The combustible gas (combustion gas) generated in the tubular flame burner may be near the limit of the flammability limit depending on the composition or temperature. According to the above characteristic configuration, since the preheating part has the pilot burner that ignites the combustion gas generated in the tubular flame burner, even if the preheating part blows off, it is sent from the tubular flame burner by the always-ignited pilot burner. The combustion gas can be reliably ignited, or by supplying heat and radicals from the pilot burner, the combustion in the preheating part can be stably continued.

  Another characteristic configuration of the heating device according to the present invention is that the heating material of the reducing combustion gas generated in the tubular flame burner is arranged downstream of the tubular flame burner in the supply direction of the heated material. It is in the point which has the downstream flow control means which suppresses the flow to the downstream of a supply direction.

  According to the above characteristic configuration, the downstream flow suppressing means for suppressing the flow of the combustion gas generated in the tubular flame burner to the downstream side in the supply direction of the heated material is the supply direction of the heated material to the tubular flame burner. Therefore, the combustion gas flows to the upstream side in the supply direction of the material to be heated with respect to the tubular flame burner. Therefore, the combustion gas can be efficiently sent to the preheating portion arranged on the upstream side in the supply direction of the material to be heated of the tubular flame burner. Further, in the tubular flame burner, the moving direction of the material to be heated and the direction in which the combustion gas flows are reversed (counterflow), so that the material to be heated can be efficiently heated.

  Another characteristic configuration of the heating device according to the present invention is that the tubular flame burner is disposed in a state where the axial direction of the combustion chamber is oriented in the vertical direction, and the tubular flame burner is disposed below the combustion chamber of the tubular flame burner. It has the holding furnace which stores the to-be-heated material fuse | melted in (4).

  According to the above characteristic configuration, the tubular flame burner is disposed in a state in which the axial direction of the combustion chamber is oriented in the vertical direction, and the holding furnace is disposed below the combustion chamber of the tubular flame burner, so that it is heated by the tubular flame burner. The molten material to be heated can be recovered in the holding furnace without adhering to the inner wall of the combustion chamber of the tubular flame burner. In addition, since the molten material to be heated is separated downward from the material to be heated by gravity, the heat generated in the tubular flame burner can be effectively used for melting the material to be heated, and the heating device can be downsized to reduce heat storage loss.・ It is also possible to reduce heat dissipation loss.

  Another characteristic configuration of the heating apparatus according to the present invention is that it includes a molding machine that forms raw materials into a linear or rod shape to be heated and supplies them to the material supply unit.

  Materials (raw materials) such as aluminum and zinc that are subjected to melting usually circulate in a state of being primarily formed in an ingot or the like. Since the energy required for mechanically forming such a raw material into a linear or rod shape is not so large, it can be offset by the effect of promoting heat transfer by melting the raw material after forming it into a linear or rod shape. That is, according to the above-described characteristic configuration, since the raw material is formed into a linear shape or a rod shape to be a material to be heated and is supplied to the material supply unit, a heating device that saves energy as a whole can be provided.

  Another characteristic configuration of the heating device according to the present invention is that the heating material of the reducing combustion gas generated in the tubular flame burner is arranged upstream of the tubular flame burner in the supply direction of the heated material. An upstream flow suppressing means that suppresses the flow to the upstream side in the supply direction, and a reducing combustion gas that is disposed upstream of the tubular flame burner in the supply direction of the material to be heated and is generated in the tubular flame burner And a combustion gas for sending combustion gas from the holding furnace to the upstream side in the direction of supply of the heated material with respect to the upstream flow suppressing means And a supply path.

  According to the above characteristic configuration, the upstream side flow suppressing means for suppressing the flow of the combustion gas generated in the tubular flame burner to the upstream side is arranged on the upstream side of the tubular flame burner. It flows into the holding furnace arranged below, that is, downstream of the tubular flame burner. As a result, the inside of the holding furnace is filled with high-temperature and reducing combustion gas, so that it is possible to prevent the molten material to be heated stored in the holding furnace from being oxidized while maintaining a molten state. In this case, the combustion gas is not sent directly to the preheating portion arranged on the upstream side of the tubular flame burner, but it has a combustion gas supply path for sending the combustion gas from the holding furnace to the upstream side of the flow suppressing means. Thus, it is possible to preheat the material to be heated by sending the combustion gas from the holding furnace to the preheating portion for combustion. That is, according to the above-described characteristic configuration, the combustion gas generated in the tubular flame burner can be guided to the holding furnace and the preheating portion in order, so that the amount of heat, the reducing atmosphere, and the fuel of the combustion gas can be effectively used.

  Another characteristic configuration of the heating device according to the present invention is that the holding furnace includes an outlet through which a material to be heated stored in a molten state is taken out, and a pilot burner that is provided near the outlet and ignites combustion gas. It is in the point which has.

  Combustion gas supplied to the holding furnace from the tubular flame burner contains unburned fuel, and may contain carbon monoxide due to incomplete combustion when hydrocarbons are used as the fuel. Risk of carbon monoxide poisoning. According to the above characteristic configuration, the holding furnace has the take-out port from which the material to be heated (molten state) is taken out and the pilot burner provided in the vicinity thereof, so when taking out the molten material to be heated from the take-out port Since the combustion gas is ignited by the always-ignited pilot burner, it is possible to avoid the situation where the combustion gas flows out from the holding furnace, and to prevent the occurrence of an unexpected leakage gas explosion, explosion and carbon monoxide poisoning accident. .

The perspective view of the heating device concerning a 1st embodiment. The perspective view of the heating apparatus which concerns on 2nd Embodiment.

[First Embodiment]
Hereinafter, the heating apparatus 1 and the heating method will be described with reference to FIG. FIG. 1 is a perspective view showing the configuration of the heating device 1. As shown in FIG. 1, the heating device 1 according to the first embodiment includes a material delivery unit F (material supply unit), an introduction unit 50, and a preheating unit 40 along the axial direction (arrow A in the drawing). And the connection part 51, the tubular flame burner 10, the cooling part 52, and the material collection | recovery part W (material supply part). The introduction part 50, the preheating part 40, the connecting part 51, the tubular flame burner 10, and the cooling part 52 are all tubular members having the same inner diameter, and the tubular space inside thereof is communicated. In the state, the shafts are connected and connected in the axial direction in the order described above with the shafts aligned along a straight line. In the present embodiment, the material delivery unit F and the material recovery unit W constitute a material supply unit.

<Material delivery part F>
The material delivery unit F supplies the material to be heated M to the opening of the introduction unit 50. The material to be heated M supplied from the material delivery unit F and heated by the tubular flame burner 10 is a linear or rod-shaped material, such as a steel wire or a non-ferrous metal such as a thin copper wire. The material M to be heated passes through the vicinity of the center of the internal space of the tubular introduction part 50, the preheating part 40, the connection part 51, the tubular flame burner 10, and the cooling part 52, and is sent to the material recovery part W. That is, the material delivery unit F supplies the material to be heated M along the axial direction of the combustion chamber 11 to the radial center of the combustion chamber 11 that is the internal space of the tubular flame burner 10. The material to be heated M supplied to the introduction unit 50 may be one, or a plurality (for example, 10) of the material to be heated M may be supplied to the introduction unit 50 at a time.
Hereinafter, the upstream side in the supply direction of the material to be heated M along the axial direction of the introduction unit 50 and the like is simply referred to as “upstream side”, and the downstream side in the supply direction of the material to be heated M is simply referred to as “downstream side”.

<Introduction unit 50>
The introduction part 50 is a tubular member having a cylindrical space inside, and the material to be heated M is supplied from the opening on the upstream side. The connecting part 51 has a gas discharge part E. Combustion exhaust gas generated by combustion of combustion gas in the preheating unit 40 flows into the introduction unit 50 from the preheating unit 40 connected downstream thereof, and the combustion exhaust gas passes through the gas discharge unit E and flows into the heating device 1. It is discharged outside.

<Preheating part 40>
The preheating unit 40 is a tubular member having a cylindrical preheating combustion chamber 41 inside, and is connected to the downstream side of the introduction unit 50. The wall surface of the preheating combustion chamber 41 is provided with a slit 42 that opens along the axial direction. In the present embodiment, two slits 42 are provided at positions symmetrical with respect to the axis of the preheating combustion chamber 41, but three or more slits 42 may be provided. When it is necessary to increase the amount of preheating or when the unburned gas is below the flammable concentration, it is possible to premix the fuel with the oxidizer or use a part of the slit for fuel supply. is there.

  An oxidant is supplied to the slit 42 from the oxidant supply path 32, and the oxidant is ejected from the slit 42 toward the tangential direction of the wall surface of the preheating combustion chamber 41. On the other hand, the combustion gas generated in the tubular flame burner 10 is supplied from the opening on the downstream side of the preheating combustion chamber 41. Then, the oxidant and the combustion gas are mixed inside the preheating combustion chamber 41, and ignited by a pilot burner (not shown) to burn the combustion gas. That is, in the preheating unit 40, the oxidant is swirled from the periphery of the preheating combustion chamber 41 in the tangential direction of the inner wall thereof, the combustion gas is supplied from the axial direction, and the combustion gas burns. The flame by combustion becomes cylindrical shape, and the to-be-heated material M is heated by the flame. Although the inside of the preheating combustion chamber 41 may be an oxidizing atmosphere, it is possible to perform preheating in a temperature range in which the material to be heated M is not oxidized by appropriately adjusting the amount and speed of the oxidizing agent. is there.

The oxidant supply path 32 is provided with a flow rate adjustment valve 24 that controls the flow rate of the oxidant, and the flow rate adjustment valve 24 is controlled by the control device 20. That is, the flow rate of the oxidant supplied to the slit 42 is controlled by the control device 20.
As the oxidizing agent supplied to the slit 42, the same oxidizing agent as that supplied to the tubular flame burner 10 described later is used.

<Connecting part 51>
The connecting part 51 is a tubular member having a cylindrical space inside, and is connected to the downstream side of the preheating part 40. A part of the flame and the combustion gas flow into the connecting portion 51 from the tubular flame burner 10 connected to the downstream side, and the combustion gas is sent to the preheating portion 40 on the upstream side. The tubular flame burner 10 needs to be maintained at a predetermined temperature required for heating and melting the material to be heated M for a predetermined time, while the preheating unit 40 is lower so that the oxidation rate of the material to be heated M does not become a problem. Need to keep temperature. Therefore, the connection part 51 is arrange | positioned with required length and heat insulation.

<Tubular flame burner 10>
In the tubular flame burner 10, an upstream tubular flame burner 10a and a downstream tubular flame burner 10b are provided in a plurality of stages (two stages) adjacent to each other in the axial direction.
The tubular flame burner 10 a is a tubular member having a cylindrical combustion chamber 11 a inside, and is connected to the downstream side of the connecting portion 51. The inner wall 15a (wall surface) of the combustion chamber 11a is provided with a slit 12a that opens along the axial direction. And it is comprised so that the gaseous mixture of an oxidizing agent and a fuel may be ejected from the slit 12a to the combustion chamber 11, and a swirl combustion may be carried out.
The tubular flame burner 10b is a tubular member having a cylindrical combustion chamber 11b inside, and is connected to the downstream side of the tubular flame burner 10a. The inner wall 15b (wall surface) of the combustion chamber 11b is provided with a slit 12b that opens along the axial direction. A gas mixture of oxidant and fuel is ejected from the slit 12b into the combustion chamber 11 for swirling combustion.
Two slits 12a and 12b are provided at positions symmetric with respect to the axes of the combustion chambers 11a and 11b, respectively, but three or more slits may be provided.

  As the fuel supplied to the tubular flame burner 10, gaseous fuel (eg, natural gas) mainly containing hydrogen or hydrocarbons, or atomized or vaporized liquid fuel (eg, heavy oil) can be used. As the oxidizing agent, air, gaseous oxygen (oxygen 100%), oxygen-enriched air (for example, air containing 40% or more by volume) or a mixed gas of carbon dioxide and oxygen can be used.

  Connected to the tubular flame burner 10 are fuel supply passages 30a and 30b for supplying a mixed gas of fuel and oxidant to the slits 12a and 12b. A fuel supply path 30 for supplying fuel and an oxidant supply path 31 for supplying an oxidant are connected to the fuel supply paths 30 a and 30 b via a venturi mixer 26. The fuel supplied from the fuel supply path 30 and the oxidant supplied from the oxidant supply path 31 are mixed by the venturi mixer 26, and the mixed gas is supplied to the slits 12a and 12b through the fuel supply paths 30a and 30b.

  The fuel supply passages 30a and 30b are provided with flow rate adjusting valves 23a and 23b for adjusting the flow rate of the mixed gas flowing therethrough. The fuel supply passage 30 and the oxidant supply passage 31 are provided with flow rate adjusting valves 21 and 22 for adjusting the flow rate of the gas flowing through each of them. By adjusting the opening degree of the flow rate adjusting valves 21, 22, the equivalent ratio of the fuel and the oxidant mixed by the venturi mixer 26 is changed / adjusted.

The control device 20 is configured to be able to adjust the opening degree of the flow rate adjusting valves 21, 22, 23a, 23b separately. In other words, the control device 20 adjusts the mixing ratio (equivalent ratio) of the oxidant and fuel injected from the slits 12a and 12b into the combustion chamber 11 by adjusting the opening degree of the flow rate adjusting valves 21 and 22.
In the present embodiment, the control device 20 (supply amount control means) controls the supply amount of the oxidant to the combustion chamber 11 so that the equivalence ratio is larger than 1 in the combustion chamber 11. More specifically, the combustion amount (heat generation amount) in the tubular flame burners 10a and 10b is controlled by controlling the fuel supply amount, and the equivalence ratio in the combustion chambers 11a and 11b is controlled by controlling the oxidant supply amount. To do.

  As described above, the oxidizer and the fuel are mixed in the tubular flame burners 10a and 10b from the slits 12a and 12b toward the tangential direction of the wall surface (inner wall portion 15) of the combustion chamber 11 so that the equivalent ratio becomes larger than 1. When swirling and swirling, premixed tubular flames are generated in the combustion chambers 11a and 11b. In the combustion chambers 11a and 11b, in the radial direction of the combustion chambers 11a and 11b (in the direction of arrow B in FIG. 1), in order from the inner wall portion 15 toward the shaft, an unburned region where fuel before combustion exists, And a combustion gas region where there is a reducing combustion gas generated by burning the fuel. And the to-be-heated material M sent from the material delivery part F via the introducing | transducing part 50, the preheating part 40, and the connection part 51 is supplied to the center part of the combustion chamber 11, ie, a combustion gas area | region, and high temperature combustion. Heated in a non-oxidized state by gas.

The control device 20 (supply amount control means) selects a tubular flame burner to be operated from the tubular flame burners 10a and 10b adjacent in the axial direction based on an instruction input from the operator, and controls the flow rate adjusting valves 23a and 23b. The oxidizing agent and the fuel are ejected from the slit of the selected tubular flame burner.
For example, when quenching without melting the material to be heated M having a low melting point, only the tubular flame burner 10b is selected, and the oxidant and fuel are ejected from the slit 12b. Then, a tubular flame is generated from the slit 12b on the downstream side, and the tubular flame becomes shorter than when both the tubular flame burners 10a and 10b are selected. And quenching can be performed at an appropriate temperature.
For example, when heating the material to be heated M that requires annealing at a high temperature, both the tubular flame burners 10a and 10b are selected, and the oxidant and fuel are ejected from the slits 12a and 12b. Then, a tubular flame is generated from both the slits 12a and 12b, and a long tubular flame in which they are integrated is generated. That is, since the tubular flame becomes longer than when only the tubular flame burner 10b is selected, the heated material M can be sufficiently heated.
In this embodiment, two slits adjacent in the axial direction are provided, but one slit may be provided, or three or more slits may be provided. Furthermore, it is good also as a rapid mixing type tubular flame burner by supplying a fuel and an oxidizing agent from a separate slit.

  A downstream side wall portion 13 (downstream flow restricting means L) having a passage hole 14 (orifice) through which the material to be heated M passes is provided at the center of the downstream end portion of the combustion chamber 11b. In the combustion chambers 11a and 11b, combustion gas is generated by burning the fuel. However, since the downstream side wall portion 13 exists at the downstream end of the combustion chamber 11b, the combustion gas is disposed downstream of the tubular flame burner 10. The main part of the combustion gas flows to the upstream side of the tubular flame burner 10 and is guided to the preheating unit 40 via the connecting part 51. That is, the mixed gas of the oxidant and fuel ejected from the slits 12a and 12b moves to the upstream side while burning while swirling, as shown by the spiral arrow drawn with a dotted line in FIG. The gas mixture (combustion gas) of the oxidant and fuel and the material to be heated M move in opposite directions as a whole (counterflow). A pilot burner that is always ignited may be provided on the downstream side of the passage hole 14 (orifice) to ignite the combustion gas leaking from the passage hole 14 (orifice).

<Cooling unit 52>
The cooling unit 52 is a tubular member having a cylindrical space inside, and is connected to the downstream side of the tubular flame burner 10. The cooling unit 52 includes a cooling gas introduction unit 53 to which the cooling gas supply path 33 is connected, and a cooling gas discharge unit 54. The material to be heated M heated by the tubular flame burner 10 is supplied to the internal space of the cooling part 52 through the passage hole 14, and the material to be heated M is cooled by the cooling gas introduced from the cooling gas introduction part 53. The In order to suppress the oxidation of the material M to be heated at a high temperature, an inert gas such as nitrogen or a rare gas is used as the cooling gas. The cooling gas that has cooled the material to be heated M is discharged from the cooling gas discharge unit 54 to the outside of the heating apparatus 1. The cooling gas discharge unit 54 may not be provided, and the cooling gas may be discharged from the opening on the downstream side of the cooling unit 52. Further, the heated material M may be cooled by spraying water or oil instead of the cooling gas. Or you may comprise so that the to-be-heated material M may be sent to an oil tank or a water tank, and may be cooled rapidly.

<Material recovery unit W>
The material recovery unit W is disposed on the downstream side of the cooling unit 52, collects the material to be heated M sent from the cooling unit 52, and winds it around a reel, for example, to a linear or bar-shaped material to be heated M. Tension is applied to reduce sagging and prevent the heated material M from coming into contact with a tubular member such as the tubular flame burner 10.

  In the heating apparatus 1 configured as described above, the oxidation containing oxygen is performed from the slits 12a and 12b that open in the axial direction on the wall surface of the cylindrical combustion chamber 11 toward the tangential direction of the wall surface of the combustion chamber 11. Using a tubular flame burner 10 in which the agent and the fuel are separately or mixed and jetted and swirled and burned, a linear or rod-like shape is formed along the axial direction of the combustion chamber 11 at the radial center of the combustion chamber 11. The material to be heated M is supplied, and the oxidant and fuel are jetted into the combustion chamber so that the equivalence ratio becomes larger than 1 in the combustion chamber 11 and swirl combustion is performed, and the material to be heated M can be heated. Further, in the combustion chamber 11, in the radial direction of the combustion chamber 11, in order from the wall surface toward the central axis of the combustion chamber 11, an unburned region where the fuel before combustion exists, a flame region where the fuel burns, A combustion gas region in which reducing combustion gas generated by combustion exists is formed, and the material to be heated M can be supplied to the combustion gas region and heated.

[Second Embodiment]
In the above-described first embodiment, the tubular member including the tubular flame burner 10 is disposed in a state where the axes are aligned with each other, and the linear or rod-shaped heated material M is heated. In the present embodiment, for example, when a metal having a relatively low melting point such as aluminum or zinc is heated and melted, a tubular member such as the tubular flame burner 10 is arranged with its axis directed in the vertical direction. Further, a holding furnace K for storing the material to be heated M melted in the tubular flame burner 10 is provided below the tubular flame burner 10.

  The heating apparatus 1 according to the second embodiment will be described below with reference to FIG. FIG. 2 is a perspective view showing the configuration of the heating device 1. As shown in FIG. 2, the heating device 1 according to the second embodiment includes a molding machine P, a material delivery unit F (material supply unit), and an introduction unit 50 along the axial direction (arrow A in the drawing). And the preheating part 40, the connection part 51, the tubular flame burner 10, and the holding furnace K. Components having the same structure and function as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and detailed description thereof may be omitted.

<Molding machine P>
The molding machine P is provided on the upstream side of the material delivery unit F, and a raw material such as an ingot is mechanically formed into a linear shape or a rod shape to be a material to be heated M, and is supplied to the material delivery unit F. As the molding machine P, a press device, a roller type stretching device, or the like is used. The molding machine P may not be provided on the upstream side of the material delivery unit F, and the raw material may be molded into the material to be heated M at a place different from the heating device 1 and supplied to the material delivery unit F. Good.

<Material delivery part F>
The material delivery unit F supplies the material to be heated M formed into a linear shape or a rod shape by the molding machine P to the opening of the introduction unit 50. The material delivery unit F is composed of two rollers that are driven by a motor (not shown). The material to be heated M is sandwiched between rotating rollers and supplied to the introduction unit 50.

<Connecting part 51>
The connecting part 51 has a combustion gas supply part 135. The combustion gas supply unit 135 is connected to the combustion gas supply path 134 and introduces the combustion gas discharged from the combustion gas discharge unit 133 of the holding furnace K described later into the internal space of the connection unit 51. The combustion gas is guided to the preheating unit 40 disposed on the upstream side of the connecting unit 51 due to the presence of an upstream side wall 113 described later, and is mixed with the oxidant supplied in the preheating unit 40 and burned.

<Tubular flame burner 10>
Unlike the first embodiment, the tubular flame burner 10 is arranged with its axis oriented in the vertical direction. Therefore, the heated material M heated and melted by the tubular flame burner 10 is immediately separated from the heated material M by the action of gravity and falls downward, and is melted in the holding chamber 136 of the holding furnace K. Retained.

  Also in the present embodiment, as in the first embodiment, the oxidant and the fuel are mixed and jetted and swirled and burned so that the equivalence ratio is greater than 1 in the combustion chamber 11, so that a tubular flame is generated in the combustion chamber 11. The central portion becomes a reducing atmosphere, and the supplied heated material M is melted in a non-oxidized state.

  Unlike the first embodiment, the tubular flame burner 10 has an upstream side wall portion 113 (upstream side) having a passage hole 114 (orifice) through which the material to be heated M passes at the center at the upstream end portion of the combustion chamber 11a. Distribution restraining means U) are provided. Due to the presence of the upstream side wall portion 113, the combustion gas is suppressed from flowing into the connecting portion 51 arranged on the upstream side of the tubular flame burner 10, and most of the combustion gas flows to the downstream side of the tubular flame burner 10, Guided to holding furnace K. That is, the mixed gas of the oxidant and fuel ejected from the slits 12a and 12b moves downstream while burning while swirling as shown by a spiral arrow drawn by a dotted line in FIG. The gas mixture (combustion gas) of the oxidant and fuel and the material to be heated M move in the same direction as a whole.

<Holding furnace K>
The holding furnace K is disposed below the tubular flame burner 10 in a state where the holding chamber 136 therein and the combustion chamber 11 of the tubular flame burner 10 are communicated with each other. The holding chamber 136 is supplied from the tubular flame burner 10 with the material to be heated M in a dissolved state and the combustion gas generated by the combustion of the fuel. Since the inside of the holding chamber 136 is filled with high-temperature combustion gas, the molten material M to be heated is stored while being kept in a molten state. Further, since the combustion gas is a reducing atmosphere, oxidation of the heated material M in the holding chamber 136 is suppressed. While the material to be heated M is stored in the holding furnace K while being kept in a molten state, other trace components that form the alloy are added to form a molten alloy, and the alloy composition and temperature are stabilized during the storage. Is done.

  The holding furnace K is provided with a combustion gas discharge part 133. The combustion gas discharge unit 133 guides the combustion gas filled in the holding chamber 136 to the combustion gas supply path 134 and supplies the combustion gas to the preheating unit 40 through the combustion gas supply unit 135 and the connection unit 51.

  The holding furnace K has an outlet 137 for taking out the molten material M to be heated, and a pilot burner (not shown) provided in the vicinity of the outlet 137. The combustion gas supplied to the holding chamber 136 from the tubular flame burner 10 includes unburned fuel because combustion in the tubular flame burner 10 sets the equivalent ratio of oxygen to fuel to be greater than 1. ing. Moreover, when using a hydrocarbon as a fuel, carbon monoxide may be contained by incomplete combustion. If a pilot burner is provided in the vicinity of the outlet 137, the combustion gas is ignited when the material to be heated M is taken out from the outlet 137, so that an unexpected ignition or carbon monoxide poisoning accident can be prevented. It is safe.

[Another embodiment]
(1)
In the first and second embodiments described above, the fuel and the oxidant are mixed by the venturi mixer 26 and ejected from the slits 12a and 12b of the tubular flame burner 10, but the oxidant and the fuel are mixed. You may make it eject from the slits 12a and 12b of the tubular flame burner 10 separately. For example, an oxidant may be ejected from one of the two slits 12 a provided at positions symmetrical with respect to the axis of the combustion chamber 11, and fuel may be ejected from the other and rapidly mixed inside the combustion chamber 11. . The same applies to the slit 12b. In this case, since so-called backfire does not occur, combustion can be performed safely.

(2)
In the first embodiment and the second embodiment described above, the control device 20 (supply amount control means) controls the flow rate adjustment valve 21 and the flow rate adjustment valve 24 so that the equivalence ratio in the combustion chamber 11 becomes greater than 1. Although the amount of oxidant supplied to the combustion chamber 11 was controlled, the flow rate adjustment valve 21 and the flow rate adjustment valve 24 were manually adjusted so that the equivalent ratio in the combustion chamber 11 was greater than 1. May be ejected into the combustion chamber 11.

(3)
In 1st Embodiment and 2nd Embodiment, even if the oxidizing agent supplied to the slits 12a and 12b of the tubular flame burner 10 and the oxidizing agent supplied to the slit 42 of the preheating part 40 are the same compositions. It may be a different composition. For example, oxygen-enriched air may be supplied to the slits 12 a and 12 b of the tubular flame burner 10, and air may be supplied to the slit 42 of the preheating unit 40.

(4)
In the second embodiment, a blower may be provided on the downstream side of the combustion gas supply path 134 or the gas discharge part E, the combustion gas may be sucked from the holding chamber 136, and the inside of the holding chamber 136 may be set to a negative pressure. Alternatively, the gas discharge part E may be connected to a chimney and the combustion gas may be sucked by the draft effect. In this case, since the combustion gas is prevented from leaking from the outlet 137, the heating device 1 with higher safety can be realized.

(5)
In the first embodiment, a downstream side wall portion 13 (downstream flow restricting means L) having an orifice is provided at the downstream end of the combustion chamber 11, and most of the combustion gas is directed upstream of the tubular flame burner 10. Led. Alternatively or in addition, the gas discharge part E may be connected to the chimney and the combustion gas may be led to the upstream side by the draft effect, or an induction fan is provided in the gas discharge part E for suction. The combustion gas may be guided upstream. The same applies to the second embodiment.

  The heating device and heating method of the present invention suppresses oxidation during heating of a linear or rod-shaped material to be heated, thereby improving product quality and yield, and reducing the size, energy and cost of the device. It can be used effectively as possible.

1: Heating device 10a: Tubular flame burner 10b: Tubular flame burner 11: Combustion chamber 12a: Slit 12b: Slit 13: Downstream side wall (downstream flow suppression means L)
14: Passing hole (downstream flow restricting means L)
15: Inner wall portion 20: Control device (supply amount control means)
40: Preheating part 41: Preheating combustion chamber 42: Slit 113: Upstream side wall part (upstream flow control means U)
114: Passing hole (upstream flow restricting means U)
134: combustion gas supply path 136: holding chamber 137: outlet F: material delivery section (material supply section)
K: Holding furnace M: Heated material P: Molding machine W: Material recovery unit (material supply unit)

Claims (13)

Tubular combustion in which oxidant and fuel are jetted separately or mixed and jetted from a slit that opens along the axial direction to the wall surface of the cylindrical combustion chamber toward the tangential direction of the wall surface of the combustion chamber With a flame burner,
A material supply unit for supplying a linear or rod-shaped material to be heated along the axial direction of the combustion chamber to the radial center of the combustion chamber;
A heating apparatus comprising supply amount control means for controlling the supply amount of the oxidant to the combustion chamber so that the equivalence ratio is greater than 1 in the combustion chamber.   In the combustion chamber, in the radial direction of the combustion chamber, in order from the wall surface toward the central axis of the combustion chamber, an unburned region where fuel and oxidant before combustion exist, and a flame in which a combustion reaction of the fuel proceeds The region and the combustion gas region where the reducing combustion gas after the completion of the combustion reaction is formed in concentric layers, and the material supply unit supplies the material to be heated to the combustion gas region. Heating device.   The heating apparatus according to claim 1, further comprising: a plurality of stages of the tubular flame burners adjacent in the axial direction, wherein the supply amount control means selects the tubular flame burner to be operated.   A preheating unit that is disposed upstream of the tubular flame burner in the supply direction of the material to be heated, and heats the material to be heated by mixing the reducing combustion gas generated in the tubular flame burner with an oxidant and burning it. The heating apparatus according to any one of claims 1 to 3, wherein   The preheating portion has a cylindrical preheating combustion chamber, and an oxidant is jetted from a slit opening along the axial direction in the wall surface of the preheating combustion chamber toward the tangential direction of the wall surface of the preheating combustion chamber, The heating apparatus according to claim 4, wherein the reducing combustion gas generated in the tubular flame burner is burned.   The heating apparatus according to claim 4 or 5, wherein the preheating unit includes a pilot burner that ignites reducing combustion gas generated in the tubular flame burner.   A downstream side that is disposed downstream of the tubular flame burner in the supply direction of the material to be heated and suppresses the flow of reducing combustion gas generated in the tubular flame burner to the downstream side in the supply direction of the material to be heated. The heating apparatus according to any one of claims 4 to 6, further comprising a circulation suppressing means.   A holding furnace in which the tubular flame burner is disposed with the axial direction of the combustion chamber oriented in the vertical direction, and the material to be heated melted in the tubular flame burner is stored below the combustion chamber of the tubular flame burner. The heating apparatus according to claim 1, comprising:   The heating apparatus according to claim 8, further comprising a molding machine that forms a raw material into a linear shape or a rod shape to be a material to be heated, and supplies the material to the material supply unit. An upstream side that is disposed upstream of the tubular flame burner in the supply direction of the material to be heated and suppresses the flow of reducing combustion gas generated in the tubular flame burner to the upstream side in the supply direction of the material to be heated. Distribution restraint means,
A preheating unit that is disposed upstream of the tubular flame burner in the supply direction of the material to be heated, and heats the material to be heated by mixing the reducing combustion gas generated in the tubular flame burner with an oxidant and burning it. When,
10. The heating device according to claim 8, further comprising a combustion gas supply path that sends combustion gas from the holding furnace to the upstream side in the supply direction of the material to be heated with respect to the upstream side flow suppression unit.   The said holding furnace has any one of the outlets from which the to-be-heated material stored by the molten state is taken out, and the pilot burner provided in the vicinity of the said outlets, and igniting combustion gas. Heating device. Tubular combustion in which oxidant and fuel are jetted separately or mixed and jetted from a slit that opens along the axial direction to the wall surface of the cylindrical combustion chamber toward the tangential direction of the wall surface of the combustion chamber Using a flame burner,
Supplying a linear or rod-shaped material to be heated along the axial direction of the combustion chamber to the central portion in the radial direction of the combustion chamber,
A heating method in which an oxidizing agent and fuel are jetted into the combustion chamber so that the equivalence ratio is greater than 1 in the combustion chamber, and swirl combustion is performed to heat the heated material.   In the combustion chamber, in the radial direction of the combustion chamber, in order from the wall surface toward the central axis of the combustion chamber, an unburned region where fuel and oxidant before combustion exist and a combustion reaction of the fuel proceed. The heating method according to claim 12, wherein a flame region and a combustion gas region in which a reducing combustion gas exists after completion of the combustion reaction are formed in concentric layers, and the material to be heated is supplied to the combustion gas region.

Images