JPH0134075Y2 - - Google Patents

Description

[Detailed description of the invention] (Technical field) The present invention relates to a device for feeding materials into a cupora furnace, and is particularly suitable for producing hot metal such as ingots such as die powder, or additives such as deoxidizing materials and slag-forming materials. The present invention relates to a material feeding device that can easily and effectively feed powdered or finely divided material (raw material) into a cupora furnace.

(Prior art and its problems) A cupola furnace has been widely used as a melting furnace for cast iron castings, and is a vertical cylindrical furnace filled with coke from the bottom to a predetermined height. On top of this, bullion metals such as pig iron, pig scraps, steel scraps, and refill materials are alternately charged at a fixed ratio with coke, and the coke is combusted by blowing air through the tuyere with the filling up to the charging port. The structure is such that the heat gradually melts the metal from the bottom.

The molten metal (molten metal) accumulates in the sump at the bottom and is continuously taken out from the tap, but once melting begins, the filling material gradually descends inside the furnace. During operation, metals and coke are continuously introduced into the furnace through a charging port provided at the top of the furnace to replenish these materials, and the charging port is always kept filled.

By the way, when it comes to materials (raw materials) such as bullion that are introduced into the furnace from the charging port during or during operation, it is important to improve operability and workability and to use molten metal with good components. In order to obtain this, a material formed into a block of a predetermined size is used.

Among these, in the case of such a Kyupora furnace,
In order to prevent oxidation of the molten metal caused by excessive oxidation of the base metal in the preheating zone located in the upper part of the furnace, materials with a large surface area compared to the volume such as pig iron scraps and steel scraps such as die powder are used. When it was introduced, it was necessary to form it into a block of a predetermined size, which resulted in high material costs due to shipping and processing costs to the steelworks, and low yields led to high melting costs. The problem was that it was expensive and that it was difficult to feed it into the furnace.

(Solution Means) Here, the present invention was made against the background of the above-mentioned circumstances, and its feature is that it accommodates powdered or finely divided materials for hot metal production such as drying powder. The material is cut out from the lower part of the hopper and is introduced into the cupola furnace through a conveying path by the pressure of the supplied compressed air, while the cupola discharged from the upper part of the cupola furnace. An exhaust gas exhaust path is connected to the conveying path or the lower part of the hopper, so that the cupora exhaust gas in the exhaust path can be guided into the hopper, and a forced exhaust means is provided at the upper part of the hopper, so that the exhaust gas inside the hopper is The cupola exhaust gas guided by the hopper is made to flow between the materials housed in the hopper, and is suctioned and exhausted by the forced exhaust means.

(Effect of the invention) In other words, in the material supply device having the structure according to the invention, base metals such as pig iron scraps such as die powder and steel scraps remain in a powdered or finely divided state. , will be introduced into the cupola furnace by the pressure of compressed air, but the cupola exhaust gas will be led into the hopper where these metals are stored, and before being supplied into the furnace, it will be introduced into the cupola furnace. After being effectively preheated and moisture and oil removed, the preheated powder metals are placed in a furnace in the melting zone or superheated zone, thereby preventing excessive oxidation of these metals. Therefore, it is possible to advantageously obtain a molten metal having good components.

Therefore, by using the material supply device according to the present invention, there is no need to form metal into a block or other shape as in the past, and iron scraps, steel scraps, etc. can be used in their original form. As a result, material costs can be effectively reduced and yields improved, melting costs can be reduced, and materials can be charged into the cupola furnace using compressed air. Since this is done using pressure, workability can be effectively improved.

Furthermore, in such a material supply device, since the cupora exhaust gas is circulated between the materials housed in the hopper and then discharged, the dust contained in the exhaust gas is effectively adsorbed. In addition to being removed, the temperature of the exhaust gas can be lowered and the exhaust gas can be purified.

(Example) In order to clarify the present invention more specifically, an example having a structure according to the present invention will be described in detail below with reference to the drawings.

First, FIG. 1 shows an embodiment of a cupola apparatus equipped with a material supply device structured according to the present invention.

In this figure, 10 is a general type of cupola used for melting foundry metals,
It has a furnace 12 made of a refractory material and having a vertical cylindrical shape, and a wind box 16 that stores combustion air sent through an air passage 14. A blow pipe 18 extends from this wind box 16, and its tip is a tuyere 20.
The combustion air contained and held in the wind box 16 is blown into the furnace 12 from there.

On the other hand, in the figure, 22 is a hopper, and inside the hopper, ingots 24 such as pig iron scraps and steel scraps to be fed into the furnace 12 are stored in a powdered or finely divided state. ing. The hopper 22 is equipped with an axial fan 50 as a forced exhaust means at its upper part.
The internal air is forcibly exhausted through the upper exhaust pipe 52 by the action of
By rotating the screw 28 around the axis, a predetermined amount of the metal 24 housed in the hopper 22 is cut out, and a conveyor connected via the hopper communication valve 30 is cut out. Road 3
It is designed to be sent within 2 days. In addition, the screw 28 of the screw type feeder 26 is as follows:
As clearly shown in FIG.
and a coil spring 36 fixed to the tip of the rotating shaft 34.
is rotated by a motor 38.

The other end of the conveying path 32 through which the metal 24 accommodated in the hopper 22 is sent out by the screw-type sending device 26 is positioned at the tuyere 20 of the cupola 10 and placed inside the furnace 12. is communicated with.

Further, a compressed air supply path 40 is connected to this conveyance path 32 at a location slightly closer to the cupola than the portion where the hopper communication valve 30 is provided. By opening the compressed air control valve 42, compressed air supplied from a predetermined air pressure source such as an air compressor is blown into the conveying path 32. Furthermore, in this conveyance path 32,
A discharge path 44 is connected to a portion closer to the cupola than the portion where the hopper communication valve 30 is provided. Cupora combustion exhaust gas discharged from the upper part of the cupola 10 is guided into the exhaust passage 44 either directly or through a heat exchanger or the like.
These exhaust gases are introduced into the conveyance path 32 by opening an exhaust gas control valve 46 provided above. An in-furnace communication valve 4 is provided on the conveyance path 32 on the cupola side from the openings of the compressed air supply path 40 and the discharge path 44.
8 are provided, thereby providing a compressed air supply channel 40 and a discharge channel 4, as is clear from the figure.
4 are connected to and opened to the conveyance path 32 between the hopper communication valve 30 and the furnace communication valve 48, respectively.

In the cupola apparatus having the above structure, the axial fan 50 is operated with the compressed air control valve 42 and the furnace communication valve 48 closed, and the exhaust gas control valve 46 and the hopper communication valve 30 opened. By operating the hopper 22 to forcibly discharge the atmospheric gas to the outside, the cupola exhaust gas guided into the conveyance path 32 through the exhaust path 44 is forcibly introduced from the lower part of the hopper 22, and the hopper The powder passes between the powder, granular or subdivided ingots 24 housed in the ingots 22 and is exhausted through the upper exhaust pipe 52. In addition, the screw 28 arranged at the bottom of the hopper 22 is
As described above, since the coil spring 36 is used, there is no problem in introducing such exhaust gas into the hopper 22. The heat of the exhaust gas effectively preheats the base metal 24, and evaporates oil and moisture adhering to the base metal 24, thereby drying the base metal 24, thereby making the base metal suitable as a melting material. It can be said that

Then, the axial flow fan 50 is stopped, the exhaust gas control valve 46 is closed, and the screw type delivery machine 2
After cutting out a predetermined amount of metal 24 into the conveyance path 32 in step 6, the hopper communication valve 30 is closed, while
With the furnace communication valve 48 open, the compressed air control valve 48 is momentarily opened to transfer the compressed air supplied from the compressed air supply path 40 to the conveyance path 3.
By blowing into the metal 2, the pressure of this compressed air causes the metal 2 cut into the discharge path 32 to be removed.
4 will be introduced into the cupora furnace 12 through the tuyere 20. Therefore, by repeatedly controlling the operation of the hopper communication valve 30, the compressed air control valve 42, and the screw type feeder 26, the furnace 12 of the metal 24 can be
This means that the supply to the inside of the country will be carried out effectively.

In addition, the supply of the bullion 24 into the hopper 22, which is performed in conjunction with such an operation, is as follows.
Stop the axial flow fan 50 and close the hopper communication valve 30.
This can be easily done by opening the material supply port 54 provided at the top of the closed state.

That is, in the cupola device in this embodiment, the base metal 24 is dried and preheated in advance,
Since the ingot 24 is introduced into the furnace 12 at its tuyere, that is, the portion called the superheat zone, it is possible to effectively prevent the ingot 24 from being oxidized in the furnace 12. Since these metal base metals 24 have a powder-like or finely divided form, they can be rapidly melted in a superheated region, thereby making it possible to obtain a high-quality molten metal.

Therefore, by using a material supply device with such a structure, it becomes possible to use raw metals such as iron scraps and steel scraps as raw materials in powdered or finely divided form. Therefore, it is possible to effectively reduce the cost of raw metal materials and improve the yield, and the melting cost can be effectively reduced.

In addition, in the material supply device in this embodiment, the operation control is performed by the hopper communication valve 30,
Compressed air control valve 42, exhaust gas control valve 4
6. The furnace communication valve 48, the axial flow fan 50, and the screw type delivery device 26 are operated in conjunction with each other by an automatic control device (not shown) or manually, and The amount of bullion 24 supplied into the furnace 12 is
By controlling the rotational speed of the screw 28 and the time interval of compressed air blowing, the material feeding operation can be performed with extremely good workability because the settings can be made easily and accurately.

Furthermore, in such a cupola apparatus, the material supply device removes dust contained in the exhaust gas discharged from the cupola furnace, and lowers the temperature of the exhaust gas, thereby reducing the temperature of the exhaust gas. It is also possible to achieve effects such as effectively cleaning the exhaust gas of the cupora reactor.

Furthermore, in the cupola apparatus of this embodiment, compressed air for feeding the metal 24 into the furnace 12 is intermittently blown into the furnace 12. This means that the impact on people's lives can be reduced as much as possible. However, in such an apparatus, while the axial flow fan 50 is stopped and the exhaust gas control valve 46 is closed, the screw-type feeder 26 is operated with the hopper communication valve 30 and the furnace communication valve 48 open, and the ingot is removed. Of course, it is also possible to continuously supply the ingot 24 into the furnace 12 for a predetermined period of time by continuously opening the compressed air control valve 42 while sending out the ingot 24 into the transfer furnace 32. It goes without saying that even under such operational control, the excellent effects described above can be satisfactorily expressed without being hindered in any way.

Although one embodiment having a structure according to the present invention has been described in detail above, this is a literal illustration, and the present invention should not be construed as being limited to such a specific example.

For example, in the screw type feeder 26 in the material supply device in the above embodiment, the screw 28 was composed of a coil spring 36, but a spiral blade was used around the rotation axis. It is also possible to employ a conventional screw provided therein.

Further, in the embodiment, the exhaust path 44 is connected to the conveyance path 32, and the exhaust gas is introduced from the lowest part of the hopper 22 through the conveyance path 32, so that the exhaust gas However, it is also possible to connect and open the discharge channel 44 in the lower wall of the hopper 22, for example.

Furthermore, in the cupola apparatus in the above embodiment, the ingot 24 was supplied into the furnace 12 from the tuyere 20, but in the superheated zone or melting zone located in the upper layer, the conveyance path 32
It is also possible to connect and open the furnace 12 so that the metal 24 can be introduced at those locations.

Furthermore, it is also possible to branch off a part of the combustion air guided through the air passage 14 and use it as compressed air in such a material supply device by pressurizing it using a ring blower or the like. With such a structure, fluctuations in the combustion conditions within the furnace 12 caused by the compressed air blown into the furnace 12 via the conveyance path 32 can be more effectively prevented. becomes.

Furthermore, in the above embodiment, the present invention is
Although we have shown an example of application to a device for supplying raw metals such as iron scraps and steel scraps, other applications such as Fe
The present invention can also be well applied to a material supply device for supplying additives such as ferroalloys such as -Mn and Fe-Si, and slag materials such as limestone.

In addition, the cupola furnace to which the present invention is applied is not limited to the structure shown in the above embodiments, but can also be successfully applied to cupola furnaces of various other structures. be.

Although not listed in detail, the present invention may be implemented with various changes, modifications, improvements, etc. based on the knowledge of those skilled in the art, and such embodiments may be implemented in accordance with the present invention. It goes without saying that any of these are included within the scope of the present invention as long as they do not depart from the spirit of the invention.

[Brief explanation of drawings]

FIG. 1 is a simplified diagram showing an outline of an embodiment of a material supply device constructed according to the present invention, and FIG. 2 is a side view showing the structure of a screw used in this embodiment. 10: Kyupora, 12: Furnace, 20: Tuyere, 2
2: Hopper, 24: Bullion, 26: Screw type delivery machine, 32: Conveyance path, 40: Compressed air supply path,
44: Discharge passage, 50: Axial flow fan.

Claims (1)

[Scope of utility model registration request] The material is cut out from the lower part of the hopper, which accommodates granular or finely divided material for hot metal production such as dry powder, and is transported into the cupola furnace through a conveying path by the pressure of the supplied compressed air. while connecting an exhaust path for cupora exhaust gas discharged from the upper part of the cupora furnace to the conveying path or the lower part of the hopper,
The cupola exhaust gas in the discharge passage can be guided into the hopper, and a forced exhaust means is provided in the upper part of the hopper, so that the cupola exhaust gas guided into the hopper can pass between the materials accommodated in the hopper. A device for supplying material into a cupora furnace, characterized in that the material is circulated and is suctioned and exhausted by the forced exhaust means.