JP2001201261A - Hot water tapping device of furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce cost and improve reliability. SOLUTION: A siphon pipe 12, a connection pipe 24, a vacuum pump 40 and the like are used to discharge a melt by siphon effect. The connection pipe 24 is directed upwards from the siphon pipe 12 and disposed at a specified height, and a melt-retaining part 28 having a large diameter for increasing heat capacity and a ventilation pipe 29, instantly ventilating an interior of the connection pipe 24 at prescribed intervals, are provided on the connection pipe 24 so as to periodically discharge the melt from the melt retaining part 28. A safety device 31 is provided on the connection pipe 24, and tapping of the melt is stopped, when the melt exceeds a prescribed range of the connection pipe 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tapping device for a furnace used for melting incinerated ash (main incinerated ash and fly ash) and metal.

[0002]

2. Description of the Related Art In recent years, ash melting furnaces for melting and processing incinerated ash have been receiving attention in order to further reduce the volume and detoxification of incinerated ash such as municipal waste and industrial waste. One of them is an ash melting furnace using electricity as a heat source. The electric melting method includes an arc method, a plasma method, and the like. Each method has a different heat source heating method, but heat melting is performed by expecting a frying pan effect by metal at the furnace bottom. According to these ash melting furnaces, the incinerated ash heated in the furnace melts out after a certain period of time, heavy metals sink in the lower layer, and the lighter molten ash floats in the upper layer as slag. That is, the molten metal is separated into a layer of molten metal below and a layer of molten slag above. When new incineration ash is supplied there, it is similarly heated and is separated into molten metal and molten slag. In this way, the molten metal surface gradually rises, and when the molten metal surface rises to the slag outlet, the upper layer of molten slag is discharged out of the furnace. The discharged molten slag is solidified by water cooling or air cooling. In this way, the incinerated ash becomes slag by melting, and the volume is reduced to about one third to one third.
The molten slag can be reused for construction materials and the like because the elution of heavy metals is prevented.

[0003] In this type of ash melting furnace, when the layer of molten metal in the furnace rises to the slag port, it is discharged outside the furnace and mixed with the molten slag. It is necessary to extract the molten metal. For this reason,
Conventionally, there has been adopted a method in which a tilting mechanism is provided in a furnace main body and a molten metal is discharged by tilting the furnace main body, or a method in which a tapping hole is formed in a furnace bottom and the molten metal is discharged from the hole.

[0004]

However, in the method in which the furnace is tilted and the hot water is discharged, since the furnace body is tilted together with the incidental facilities, a large-scale facility is required and the cost is large. Further, in the method in which a hole is formed in the furnace bottom to discharge hot water, since the hole in the furnace bottom is constantly exposed to a high-temperature molten metal, there is a problem that the hole is easily damaged and the reliability is not sufficient. It is an object of the present invention to solve such a conventional problem and to provide a furnace tapping device for reducing costs and improving reliability.

[0005]

In order to achieve the above object, the present invention provides a siphon tube having a molten metal inlet disposed inside a furnace and a molten metal outlet disposed outside the furnace, and a siphon tube. The molten metal is discharged by a siphon effect by using a lid mechanism capable of opening and closing a discharge port of the siphon and a decompression mechanism such as a vacuum pump connected to the siphon pipe via a connecting pipe and depressurizing the inside of the siphon pipe. The connecting pipe is piped upward at a predetermined height from the siphon pipe to prevent the molten metal from being pushed up beyond a predetermined range of the connecting pipe by a siphon effect. A diameter or large-sized molten metal holding part is provided, and the molten metal sucked up into the connecting pipe by the siphon effect is hardly cooled and held.In addition, a ventilation part for instantly ventilating the inside of the connecting pipe at regular intervals is provided. The molten metal is discharged from the molten metal holding section. In addition, on the connecting pipe, a ventilation hole provided on the wall surface of the connecting pipe, a plug member formed of a material that can be melted by the heat of the molten metal, and capable of closing the ventilation hole, outside the ventilation hole. A safety device is formed by a storage portion provided and capable of storing the molten metal flowing out of the ventilation hole, and when the molten metal is pushed up beyond a predetermined range of the connecting pipe due to a siphon effect, the pressure inside the siphon pipe is reduced. Is automatically released, and the suction of the molten metal is stopped urgently. Still further, the connecting pipe is constituted by a first pipe connected substantially vertically to an intermediate portion of the siphon pipe, and a second pipe connected substantially horizontally to the first pipe. , The second pipe is divided into at least a siphon pipe side and a decompression mechanism side, and the two are connected by a flexible pipe so that the siphon pipe can be moved.
The siphon tube is raised and lowered by a lifting device. In addition, the siphon pipe is connected to the inner pipe on the suction side which is obliquely inserted from the outside of the furnace toward the bottom of the furnace through a hole provided in the peripheral surface of the furnace or the canopy, and is connected to the inner pipe in a substantially inverted L-shape. By providing a discharge port side external pipe disposed outside the furnace, the present invention is applicable to various types of furnaces simply by providing a hole in the furnace main body, and enables the discharge of molten metal. In addition, a siphon pipe is provided with a cylindrical cover surrounding the outlet at the outlet end side, and a lid mechanism, a lid member capable of closing the siphon pipe cover, and a tilting member that drives the lid member to open and close. The drive mechanism is used to open and close the siphon tube cover to protect the outlet. In this way, using multiple pipes and a pressure reducing mechanism such as a vacuum pump, a simple structure that discharges the molten metal by the siphon effect is used to reduce costs, and the structure is independent of the furnace and is affected by high heat from the furnace. And improve reliability.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a furnace tapping device according to a first aspect of the present invention, a connecting pipe is piped at a predetermined height upward from a siphon pipe, and a connecting end of the connecting pipe with the siphon pipe. Has a molten metal holding part. From this configuration, when the siphon pipe is depressurized through the connecting pipe by the operation of the decompression mechanism,
Due to the siphon effect, the molten metal is sucked in from the suction port of the siphon pipe, sucked into the molten metal holding portion of the connecting pipe, refluxed to the discharge port of the siphon pipe, and discharged. At this time, by increasing the holding capacity of the molten metal by the molten metal holding portion on the connecting pipe to increase the heat capacity,
The molten metal sucked into the molten metal holding portion on the connecting pipe can be hardly cooled and hardened, and the molten metal can be easily discharged. According to a second aspect of the present invention, there is provided a furnace tapping device according to the first aspect, further comprising, on the connecting pipe, a vent pipe for instantaneously ventilating the inside of the connecting pipe at predetermined time intervals, and an on-off valve thereof. I have. According to this configuration, the molten metal can be reliably dropped from the molten metal holding portion on the connecting pipe by periodically instantaneously depressurizing the inside of the vent pipe during tapping, and can be discharged from the outlet through the siphon pipe. According to a third aspect of the present invention, in the furnace tapping device according to the first or second aspect, the predetermined height is at least lower than a limit height at which the molten metal is pushed up by the siphon effect. Is set to no position. With this configuration, even if the molten metal sucked by the siphon pipe is pushed up to the connecting pipe, it can be stopped in the middle of the connecting pipe. Therefore, safety can be ensured, and damage to the pressure reducing mechanism and the like can be reliably prevented. According to a fourth aspect of the present invention, there is provided a tapping device for a furnace according to any one of the first to third aspects, wherein the connecting pipe is connected to the middle portion of the siphon pipe in a substantially vertical direction. And the first
And a second pipe connected to the pipe in a substantially horizontal direction. The tapping device for a furnace according to claim 5 of the present invention, in the configuration according to claim 4, wherein the second pipe of the connecting pipe is:
It is divided into at least a siphon tube side and a decompression mechanism side, and the two are connected by a flexible tube. With these configurations, the connecting pipe can be easily piped close to the furnace, and the suction port side of the siphon pipe can be easily inserted into the furnace. According to a sixth aspect of the present invention, in the furnace tapping device of the fifth aspect, the flexible pipe is provided in a substantially inverted U shape between the divided pipes of the second pipe. With this configuration, the height of the flexible pipe can be further increased than the height of the connecting pipe, and the rise of the molten metal sucked by the siphon effect can be reliably prevented. The tapping device for a furnace according to claim 7 of the present invention is provided by claim 5 or 6.
In the above configuration, an elevating device that moves up and down the siphon tube is provided. With this configuration, the siphon tube can be moved up and down, and the siphon tube can be easily inserted into the furnace. According to an eighth aspect of the present invention, in the furnace tapping device according to any one of the first to seventh aspects, when the molten metal is pushed up beyond a predetermined range of the connecting pipe due to a siphon effect, the inside of the siphon pipe is provided. Equipped with a safety device that automatically releases pressure reduction. With this configuration, when the molten metal is pushed up beyond a predetermined range of the connecting pipe due to the siphon effect, the suction of the molten metal can be stopped urgently, safety can be ensured, and damage to the pressure reducing mechanism and the like can be prevented. It can be reliably prevented. Claim 9 of the present invention
The safety device according to claim 8, wherein the safety device is formed of a ventilation hole provided on a wall surface of the connecting pipe and a material which can be melted by the heat of the molten metal. And a housing portion provided outside the ventilation hole and capable of storing the molten metal flowing out of the ventilation hole. From this configuration, the safety device can be provided on the connecting pipe with a simple device configuration, and when the molten metal is pushed up beyond a predetermined range of the connecting pipe due to the siphon effect, the emergency stop of the suction of the molten metal is reliably performed. Can be. According to a tenth aspect of the present invention, in the furnace tapping device according to any one of the first to ninth aspects, the siphon tube is directed from the outside of the furnace toward the bottom of the furnace through a hole provided in a peripheral surface of the furnace or a canopy. An inner pipe on the suction port side that is obliquely inserted through the inner pipe, and an outer pipe on the discharge port side that is connected to the inner pipe in a substantially inverted L-shape and that is disposed outside the furnace. With this configuration, the suction port of the siphon pipe can be easily placed inside the furnace and the discharge port can be easily placed outside the furnace simply by providing holes on the peripheral surface of the furnace and the canopy. To reliably discharge the molten metal. A tapping device for a furnace according to claim 11 of the present invention, in any one of the constitutions according to claims 1 to 10, further comprises a cylindrical cover that is joined to a discharge port end side of the siphon pipe and surrounds a periphery of the discharge port. Have. With this configuration, the outlet of the siphon tube can be protected. According to a twelfth aspect of the present invention, in the furnace tapping device according to any one of the first to eleventh aspects, the lid mechanism includes a lid member capable of opening and closing the outlet of the siphon tube or its cover, and a lid member. A closed position capable of being pressed against the outlet of the siphon tube or its cover and separated from the outlet or its cover,
A tilting member is provided for tilting and guiding between an open position deviated from the outflow direction of the molten metal, and a driving device for driving the tilting member. The tapping device of the furnace according to claim 13 of the present invention,
According to a twelfth aspect of the present invention, a cylinder using a pressure reducing mechanism as a driving source is used as a driving device of the tilting member. With these configurations, the outlet side of the siphon tube can be reliably opened and closed. A tapping device for a furnace according to claim 14 of the present invention is characterized in that, in the constitution according to any one of claims 1 to 13,
The pressure reducing mechanism includes an on-off valve, a vacuum tank, and a vacuum pump, which are sequentially connected to a connecting pipe. With this configuration, the inside of the siphon tube can be quickly evacuated to reduce the pressure, and the molten metal can be quickly sucked and discharged by the siphon tube.

An embodiment of the present invention will be described below with reference to the drawings. (Embodiment) FIG. 1 shows the configuration of an embodiment of the present invention. In FIG. 1, 1 is an electric furnace, and 11 is a tapping device.

Here, the electric furnace 1 is a known plasma type ash melting furnace, and its entire configuration is shown in FIG. FIG.
, 2 is a furnace body, 3 is a molten slag discharge port provided in the furnace body 2, and 4 is a graphite electrode inserted into the furnace body 2. In addition, 10 is a molten metal. In the electric furnace 1, a hole 5 for tapping water is drilled obliquely downward from the outside of the furnace toward the inside of the furnace (furnace bottom) at a substantially middle portion of the side surface of the furnace main body 2 in the vertical direction. 5 is normally closed by a lid member 6. In addition, the hole 5 for tapping may be provided in the canopy 7 of the furnace main body 2, and its position is arbitrary.

In FIG. 1, a tapping device 11 includes a siphon pipe 12 having a molten metal inlet 13 arranged inside a furnace and a molten metal outlet 15 arranged outside the furnace, and a siphon pipe 12.
A lid mechanism 19 capable of opening and closing the discharge port 15 of the siphon pipe 12 and a siphon pipe 12 connected to the siphon pipe 12 via a connecting pipe 24.
A decompression mechanism 37 for depressurizing the inside is provided, and the molten metal in the furnace is discharged by a siphon effect.

The siphon pipe 12 is formed by bending the whole into a substantially annular shape, and has an inner pipe 14 on the suction port 13 side which can be obliquely inserted from the outside of the furnace toward the bottom of the furnace through a hole 5 for tapping water of the furnace body 2. And an outer pipe 16 on the side of the discharge port 15 which is connected to the inner pipe 14 in an inverted L-shape and is disposed outside the furnace. As shown in FIG. 3, a cylindrical cover 17 surrounding the periphery of the discharge port 15 is joined to the end of the discharge port 15. The lower part of the cover 17 is formed obliquely, and the lower opening 18 is formed.
Are directed toward the lid mechanism 19 disposed outside the electric furnace 1.

The cover mechanism 19 has a cover member 20 capable of opening and closing the cover 17 of the siphon tube 12, a closed position where the cover member 20 can be pressed against the cover 17 of the siphon tube 12, and is separated from the cover 17. A tilting member 21 for tilting and guiding between an open position deviated from the direction and a tilting member 21
And a driving device 22 for driving the. Here, the lid member 20
Is formed to have a diameter larger than the outer diameter of the opening 18 so that the opening 18 of the cover 17 can be closed. The tilting member 21 is a plate-shaped member bent in a substantially rectangular shape, and is rotatably supported at a predetermined position set outside the electric furnace 1 around the bent portion 21C as a rotation center. A lid member 20 is attached to one lower end thereof.
Is attached, and is opposed to the oblique opening 18 of the cover 17 of the siphon tube 12, and the driving device 2 is
2 is operatively connected. An air cylinder driven by the pressure reducing mechanism 37 is used as the driving device 22 of the tilting member 21. The air cylinder 22 is installed near the tilting member 21, and its operating rod 221 is connected to the tilting member 21.

The connecting pipe 24 is piped at a predetermined height upward from the siphon pipe 12. Here, the predetermined height is a height at least not lower than a limit height at which the molten metal is pushed up by the siphon effect, which is shown in FIG. 1 from the bottom of the furnace main body 2 at a predetermined height ( H). The connecting pipe 24 is connected to the middle part of the siphon pipe 12 in a substantially vertical direction and connected to a first pipe 25 having a predetermined length, and is connected to the first pipe 25 in a substantially horizontal direction. Second tube 26 having a predetermined length
The second pipe 26 is divided into at least a siphon pipe 12 side and a decompression mechanism 37 side, and the two are connected by a flexible pipe 27. The flexible pipe 27 is provided in an inverted U shape between the divided pipes of the second pipe 26. In this manner, the connecting pipe 24 is installed outside the electric furnace 1 with the second pipe 26 disposed at the predetermined height (H). On the other hand, the second tube 26
, The siphon tube 12 is configured to be detachable together with a part of the connecting tube 24, and is suspended by the elevating device 36 so as to be able to move up and down.

In such a piping structure, the connecting pipe 24
End of the first tube 2 connected to the siphon tube 12
5, a large-diameter molten metal holding portion 28 is formed on the connection end side, and the inside of the connecting pipe 24 is instantaneously ventilated at regular intervals to the pressure reducing mechanism 37 on the second pipe 26 of the connecting pipe 24. Are connected via an on-off valve 30. Further, the tapping device 1 is placed on the siphon pipe 12 side on the second pipe 26.
One emergency stop safety device 31 is provided. The safety device 31 is provided with a ventilation hole 3 provided on the wall surface of the second tube 26 (the divided tube on the siphon tube 12 side), particularly on the bottom wall surface.
2, a box member having a plug member 33 formed of a low melting point material that can be melted by the heat of the molten metal and capable of closing the ventilation hole 32, and a ventilation part 34, and formed outside the ventilation hole 32. And a housing portion 35 that is connected and can store the molten metal flowing out of the vent hole 32.

The decompression mechanism 37 includes an on-off valve 38, a vacuum tank 39, and a vacuum pump 40, which are sequentially connected to the connecting pipe 24 and installed at a predetermined position outside the electric furnace 1. The air cylinder 22 used for the lid mechanism 19 is connected to the vacuum tank 39 via the on-off valve 23 and is operated by the pressure reducing mechanism 37.

Next, the tapping operation of the tapping device will be described. First, in preparation for tapping, as shown in FIG. 1, the tapping hole 5 of the electric furnace 1 is opened, and the siphon tube 12 is inserted into the electric furnace 1. In this case, after the siphon tube 12 is moved to a predetermined height position by the lifting device 36,
The internal pipe 14 is inserted through the hole 5 for tapping water. The on-off valve 38 of the pressure reducing mechanism 37, the on-off valve 30 of the ventilation pipe 29, and the on-off valve 23 of the air cylinder 22 are closed.

In this state, first, the vacuum pump 40 is operated, and the vacuum tank 39 is evacuated to a vacuum. Subsequently, the on-off valve 23 of the air cylinder 22 is opened. Air cylinder 2
By the operation (pulling operation) 2, the tilting member 21 is tilted in the pulling direction of the air cylinder 22, and the lid member 20 is tilted and guided to the closed position. Thereby, the lid member 20 is pressed against the oblique opening 18 of the cover 17 of the siphon tube 12,
The outlet 15 is closed. Subsequently, the on-off valve 38 of the decompression mechanism 37 is opened, and the siphon tube 12 is sucked into a vacuum through the connecting tube 24. The molten metal 10 is sucked from the suction port 13 of the siphon pipe 12 by the siphon effect, is sucked up by the molten metal holding portion 28 of the connecting pipe 24, and is returned to the discharge port 15 of the siphon pipe 12. The on-off valve 23 of the air cylinder 22 is closed at a predetermined timing.
By the operation (push operation) of the air cylinder 22, the tilting member 21 is tilted in the pressing direction of the air cylinder 22, and the lid member 20 is moved to the open position. Thereby, the lid member 20 is separated from the cover 17 of the siphon tube 12, and the outlet 15 is opened. From the outlet 15 of the siphon tube 12, the molten metal 1
0 is discharged.

During the tapping operation, the first pipe 2 of the connecting pipe 24 is
5 has a larger diameter or a larger diameter than the diameter of the first pipe 25, so that the molten metal holding capacity is increased to increase the heat capacity. 2
The molten metal held in 8 is hard to cool and hard to harden. Further, during the tapping, the on-off valve 30 of the ventilation pipe 29 is momentarily opened at regular intervals, and the inside of the connection pipe 24 is instantaneously ventilated. The molten metal is reliably dropped from the molten metal holding portion 28 on the first pipe 25 before being solidified, and is discharged from the discharge port 15 through the siphon pipe 12. By the subsequent evacuation, new molten metal sucked up from the siphon pipe 12 to the connecting pipe 24 is held in the molten metal holding section 28, and is discharged again by the next ventilation. Thus, the molten metal holding section 28
The replacement of the molten metal is repeated at regular intervals, and the connecting pipe 2
4, solidification of the molten metal is reliably prevented.

In addition, in the case where a substance having a different mass is mixed into the molten metal during the tapping, the molten metal sucked up from the siphon pipe 12 may be at the height of the connecting pipe 24,
That is, when pushed up to the second pipe 26, the safety device 31 is activated. That is, when the high-temperature molten metal enters the second pipe 26 and comes into contact with the plug member 33 that closes the ventilation hole 32, the plug member 33 is instantaneously melted and the ventilation hole 32 is opened. The opening of the ventilation hole 32 allows the inside of the ventilation pipe 24 to be ventilated, and the decompression inside the ventilation pipe 24 immediately stops the suction of the molten metal. This ensures safety and prevents the expensive vacuum pump 40 and the vacuum tank 39 constituting the pressure reducing mechanism 37 from being damaged.

As described above, according to the above embodiment, since the molten metal is discharged by the siphon effect using the siphon pipe 12, the connecting pipe 24, the vacuum pump 40 and the like, the furnace body is tilted as in the conventional case. As compared with the mechanism, it is possible to realize a simple device configuration with a smaller number of parts, and it is installed separately from and independent of the electric furnace 1, and the siphon tube 12 is inserted into the furnace main body 2 when tapping. From
It is possible to reduce the influence of high heat from the furnace, and to perform maintenance such as inspection and repair easily and reliably.

Further, the connecting pipe 24 is piped at a predetermined height upward from the siphon pipe 12, and a part of the first pipe 25 of the connecting pipe 24 has a diameter larger than the diameter of the first pipe 25. Alternatively, since the large-sized molten metal holding portion 28 is provided to increase the holding capacity of the molten metal and increase the heat capacity, the molten metal sucked up by the molten metal holding portion 28 during tapping can be hardly cooled and hardened. . In addition to this, a ventilation pipe 29 that instantaneously ventilates the inside of the connecting pipe 24 at predetermined time intervals and its on-off valve 30 are connected on the second pipe 26, and the inside of the ventilation pipe 24 is periodically depressurized instantaneously. As a result, the molten metal is reliably dropped from the molten metal holding portion 28 on the connecting pipe 24 before being solidified,
It can be discharged through the siphon tube 12.

Further, since the connecting pipe 24 is provided at a predetermined height (H) which is at least not lower than the limit height at which the molten metal is pushed up by the siphon effect, the connecting pipe 24 is sucked by the siphon pipe 12. Even if the molten metal is pushed up to the connecting pipe 24, it can be stopped in the middle of the connecting pipe 24, ensuring safety and preventing damage to the pressure reducing mechanism 37 and the like.

The connecting pipe 24 is formed by a first pipe 25 connected to the siphon pipe 12 in a substantially vertical direction and a second pipe 26 connected to the first pipe 25 in a substantially horizontal direction. The second pipe 26 is divided into a siphon pipe 12 side and a decompression mechanism 37 side, and the two pipes are connected by a flexible pipe 27. Can be easily piped and the siphon pipe 1
2 can be easily inserted into the furnace. Further, since the flexible pipe 27 is provided in an inverted U shape between the divided pipes of the second pipe 26, and the flexible pipe 27 is made higher than the height of the connecting pipe 24, the rise of the molten metal is reliably prevented. be able to. Further, the siphon pipe 12 and the connecting pipe 24 on the siphon pipe 12 side are separated from the other part (the connecting pipe 24 on the decompression mechanism 37 side), and this is moved up and down by the elevating device 36. Insertion into the main body 2 can be easily performed.

Further, a safety device 31 is provided on the connecting pipe 24 so that when the molten metal is pushed up beyond a predetermined range of the connecting pipe 24 due to the siphon effect, the siphon pipe 12 automatically stops sucking up the molten metal. Because
Safety can be ensured, and the pressure reducing mechanism 37
Such damage can be reliably prevented. Further, the safety device 31 is provided with a vent hole 32 on the wall surface of the second pipe 26 and closed with a plug member 33 which can be melted by the heat of the molten metal. Since the configuration is provided by providing the accommodating portion 35, the cost can be reduced with a simple device configuration.

Further, a siphon tube 12 is formed in a substantially annular shape, and an inner tube 14 obliquely inserted from the outside of the furnace toward the bottom of the furnace through a hole 5 for tapping of the electric furnace 1, and a substantially inverted L into the inner tube 14. Since it is provided with an external pipe 16 which is continuous in a letter shape and is disposed outside the furnace, only by providing a hole in the furnace main body 2, the suction port 13 of the siphon pipe 12 is placed inside the furnace, and the discharge port 15 is placed outside the furnace. The tapping device 1 can be easily arranged, and the tapping device 1 can be applied to various types of furnaces including an existing furnace. Further, since the cylindrical cover 17 surrounding the periphery of the discharge port 15 is joined to the end side of the discharge port 15 of the siphon tube 12, the discharge port 15 of the siphon tube 12 can be reliably protected.

Further, the cover mechanism 19 is separated from the cover member 20 capable of opening and closing the cover 17 of the siphon tube 12 and the closed position where the cover member 20 can be pressed against the cover 17 of the siphon tube 12 and separated from the cover 17. Of the siphon tube 12 is reliably constituted by the tilting member 21 for tilting and guiding between the open position deviated with respect to the outflow direction and the driving device 22 for driving the tilting member 21. Can be opened and closed. Further, since an air cylinder using the pressure reducing mechanism 37 as a driving source is used as the driving device 22 of the tilting member 21, the cost can be reduced by using common components.

The decompression mechanism 37 is constituted by an on-off valve 38, a vacuum tank 39, and a vacuum pump 40, and the pressure is reduced by evacuating the inside of the siphon tube 12, so that the molten metal can be quickly passed through the siphon tube 12. Can be inhaled and exhaled.

[0027]

As described above, in the present invention, a plurality of pipes and a pressure reducing mechanism such as a vacuum pump are used to discharge the molten metal by a siphon effect. The cost can be reduced. Separate and independent installation for the furnace makes the furnace less susceptible to the heat of the furnace. In addition, maintenance such as inspection and repair can be performed easily and reliably, and reliability is improved. Can be. Further, particularly, the connecting pipe is piped upward at a predetermined height from the siphon pipe to prevent the molten metal from being pushed up beyond a predetermined range of the connecting pipe due to a siphon effect. Provide a molten metal holding part larger than the diameter, or a large size, while holding the molten metal sucked up to the connecting pipe by the siphon effect so that it is hard to cool, and providing a ventilation part that instantaneously ventilates the inside of the connecting pipe at regular intervals, Since the molten metal is periodically discharged from the molten metal holding section, solidification of the molten metal in the connecting pipe can be reliably prevented, and the molten metal can be smoothly and reliably discharged. Further, on the connecting pipe, a ventilation hole formed on the wall surface of the connecting pipe, a plug member formed of a material that can be melted by the heat of the molten metal and capable of closing the ventilation hole, A safety device is constituted by a storage portion provided on the outside and capable of storing the molten metal flowing out from the ventilation hole, and when the molten metal is pushed up beyond a predetermined range of the connecting pipe by a siphon effect, the inside of the siphon pipe is formed. Since the depressurization of the molten metal is automatically canceled and the suction of the molten metal is automatically stopped, safety can be ensured and damage to the expensive depressurizing mechanism can be surely prevented. Still further, the connecting pipe is constituted by a first pipe connected to the siphon pipe in a substantially vertical direction and a second pipe connected to the first pipe in a substantially horizontal direction. The pipe 2 is divided into at least a siphon pipe side and a decompression mechanism side, and the two are connected by a flexible pipe, and the siphon pipe is supported by a lifting device so as to be able to move up and down. An inner pipe on the suction side inserted obliquely from the outside of the furnace toward the bottom of the furnace through the provided hole, and an outer pipe on the discharge side continuous with the inner pipe in a substantially inverted L-shape and arranged outside the furnace; The tapping device can be easily applied to various types of furnaces including an existing furnace only by providing a hole in the peripheral surface or the canopy of the furnace. A siphon tube is provided with a cylindrical cover surrounding the outlet at the outlet end of the siphon tube, and the lid mechanism is provided with a lid member capable of closing the siphon tube cover, a tilting member for driving the lid member to open and close, and a tilting member. Since the outlet of the siphon tube is configured to be opened and closed via the cover with the drive mechanism, the outlet of the siphon tube can be reliably protected.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a furnace tapping device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of an electric furnace equipped with the tapping device.

FIG. 3 is a partially enlarged sectional view of an outlet of a siphon tube used in the tapping device and a lid mechanism for opening and closing the outlet.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric furnace 2 Furnace main body 3 Slag outlet of molten slag 4 Graphite electrode 5 Hole for tapping 6 Cover member 7 Canopy 10 Melt 11 Tapping device 12 Siphon tube 13 Suction port 14 Internal pipe 15 Discharge port 16 External pipe 17 Cover 18 Opening Reference Signs List 19 lid mechanism 20 lid member 21 tilting member 22 drive device (air cylinder) 221 operating rod 23 on-off valve 24 connecting pipe 25 first pipe 26 second pipe 27 flexible pipe 28 molten metal holding part 29 ventilation pipe 30 on-off valve 31 safety Device 32 Ventilation hole 33 Plug member 34 Ventilation part 35 Housing part 36 Elevating device 37 Decompression mechanism 38 On-off valve 39 Vacuum tank 40 Vacuum pump

Claims (14)

[Claims] 1. A siphon tube having an inlet for molten metal disposed in a furnace and an outlet for molten metal disposed outside the furnace, a lid mechanism capable of opening and closing the outlet of the siphon tube, and a connecting tube connected to the siphon tube. And a depressurizing mechanism for depressurizing the inside of the siphon pipe, and discharging the molten metal in the furnace by a siphon effect, wherein the connecting pipe has a predetermined height upward from the siphon pipe. A tapping device for a furnace, which is provided with a molten metal holding portion at a connection end side of a connecting pipe with a siphon pipe, which is piped. 2. The tapping device for a furnace according to claim 1, further comprising a ventilation pipe for ventilating the inside of the connection pipe instantaneously at predetermined time intervals on the connection pipe, and an on-off valve thereof. 3. The furnace tapping device according to claim 1, wherein the predetermined height is set at least at a position not lower than a limit height at which the molten metal is pushed up by the siphon effect. . 4. The connecting pipe comprises a first pipe connected to a middle portion of the siphon pipe in a substantially vertical direction, and a second pipe connected to the first pipe in a substantially horizontal direction. The tapping device for a furnace according to any one of claims 1 to 3, which is configured. 5. The tapping of a furnace according to claim 4, wherein the second pipe of the connecting pipe is divided into at least a siphon pipe side and a pressure reducing mechanism side, and the two are connected by a flexible pipe. apparatus. 6. The tapping device for a furnace according to claim 5, wherein the flexible pipe is provided in a substantially inverted U-shape between the divided pipes of the second pipe. 7. The furnace tapping device according to claim 5, further comprising a lifting device for lifting and lowering the siphon tube. 8. A safety device for automatically releasing pressure reduction inside the siphon tube when the molten metal is pushed up beyond a predetermined range of the connecting tube due to a siphon effect.
A tapping device for a furnace according to any one of claims 1 to 7. 9. A safety device comprising: a ventilation hole provided in a wall surface of a connecting pipe; a plug member formed of a material which can be melted by heat of molten metal; and a plug member capable of closing the ventilation hole; 9. A tapping device for a furnace according to claim 8, further comprising a storage portion provided outside the hole and capable of storing the molten metal flowing out of the ventilation hole. 10. A siphon tube is formed in a substantially inverted L-shape with an inner tube on a suction port side obliquely inserted from the outside of the furnace toward a bottom of the furnace through a hole provided in a peripheral surface of the furnace or a canopy, and an inner tube. 10. The furnace tapping device according to any one of claims 1 to 9, further comprising a discharge port side external pipe that is continuous and disposed outside the furnace. 11. The tapping device for a furnace according to claim 1, further comprising a cylindrical cover joined to a discharge port end side of the siphon tube and surrounding a periphery of the discharge port. 12. A lid mechanism for opening and closing a discharge port of a siphon tube or a cover thereof, and a cover member and a closed position capable of press-contacting the discharge port of the siphon tube or the cover, and separating the cover member from the discharge port or the cover. 12. A tilting member for tilting and guiding between an open position deviated with respect to the outflow direction of the molten metal and a driving device for driving the tilting member.
A tapping device for a furnace according to any one of the above. 13. The furnace tapping device according to claim 12, wherein a cylinder driven by a pressure reducing mechanism as a driving source is used as a driving device of the tilting member. 14. The furnace tapping device according to claim 1, wherein the pressure reducing mechanism includes an on-off valve, a vacuum tank, and a vacuum pump, and these are sequentially connected to the connecting pipe.