JP2001255067A - Facility for melting cold iron source and melting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent cold iron source form being hung in a preliminary heating chamber in the case that the cold iron source is melted under application of an arc melting facility having a shaft-type preliminary heating chamber directly connected to an upper segment of a melting chamber. SOLUTION: There is provided a melting facility 1 for cold iron source comprising a melting chamber 2 for melting cold iron source 18; a shaft-type preliminary heating chamber 3 directly connected to an upper part of one side of the melting chamber to perform a pre-heating of the cold iron source; arc generating electrodes 7, 8 for melting the cold iron source in the melting chamber; a cold iron source supplying means 17 for supplying the cold iron source either continuously or intermittently to keep a state that the cold iron source is present continuously with the melting chamber and the preliminary heating chamber; and molten metal discharging port 15 arranged at the melting chamber. The cold iron source in the melting chamber is melted by arc 21, and the molten metal is discharged under a state that the cold iron source is present in the melting chamber and the preliminary heating chamber when a predetermined amount of molten metal 19 is accumulated in the melting chamber. A wall surface 3A of the preliminary heating chamber where the cold iron source in the preliminary heating chamber is supplied to the melting chamber has a downward diverging state at an angle corresponding to an angle of repose.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a melting apparatus and a melting method for melting a cold iron source such as iron scrap or direct reduced iron by arc heat.

[0002]

2. Description of the Related Art In an arc melting equipment for steelmaking, a cold iron source such as iron scrap or direct reduced iron is heated and melted by arc heat generated from an electrode for arc generation and refined to produce molten steel. In order to consume power, a method of preheating a cold iron source using high-temperature exhaust gas generated from the melting chamber of the arc melting equipment during melting and melting the preheated cold iron source to reduce power consumption Many have been proposed.

For example, Japanese Patent Publication No. 6-46145 (hereinafter referred to as "prior art 1") has a shaft-type preheating chamber directly connected to a melting chamber, and a cooling chamber for one heat is provided between the melting chamber and the preheating chamber. An equipment is disclosed in which an iron source is charged for each melting, and the cold iron source is melted while being preheated by exhaust gas. In the prior art 1, since the preheating chamber is directly connected to the melting chamber, there is no need for a facility for holding and transporting the cold iron source. Since the preheating temperature of the source can be raised, the power saving effect is excellent, but every time the amount of molten steel for one heat is melted, all the cold iron sources in the preheating chamber are melted, hot water is melted, and the cold iron source is melted again. In order to restart melting by charging the chamber and preheating chamber,
Approximately 50% of the cold iron source that is melted is not preheated and is not sufficient in terms of effective utilization of exhaust gas.

[0004] To solve this problem, Japanese Patent Laid-Open No. 10-29 is disclosed.
No. 2990 (hereinafter referred to as “prior art 2”) and Japanese Patent Application Laid-Open No. 11-241889 (hereinafter referred to as “prior art 3”) have been proposed by the present inventors.

[0005] The melting method according to Prior Art 2 uses an arc melting equipment provided with a shaft-type preheating chamber directly connected to the upper part of the melting chamber, and a state in which a cold iron source is continuously present in the melting chamber and the preheating chamber. The cold iron source in the melting chamber is melted by an arc while supplying the cold iron source to the preheating chamber to maintain it, and when a predetermined amount of molten steel has accumulated in the melting chamber, there is a cold iron source in the melting chamber and the preheating chamber. It is a method of tapping molten steel in a state where it is heated. In this melting method, a cold iron source always exists in the preheating chamber and the melting chamber,
In the second and subsequent heats, all the cold iron sources to be melted are preheated by the high-temperature exhaust gas generated in the melting chamber, so that a significant reduction in power consumption can be achieved.

The arc melting equipment according to the prior art 3 is an arc melting equipment provided with a shaft type preheating chamber directly connected to the upper part of one side of the melting chamber, and a tapping section projecting from the melting chamber and having a tap hole. The cold iron source in the preheating chamber is supplied from one side where the preheating chamber of the melting chamber is provided to the other side, and the tapping section is provided in a direction different from the supply direction of the cold iron source, Further, between the portion of the melting chamber where the preheating chamber is provided and the portion where the tapping section is provided, it is possible to prevent the cold iron source from flowing into the tapping section when the melting chamber is tilted toward the tapping section. The equipment has a separation part as possible. In this arc melting equipment, the contact area between the molten steel and the cold iron source can be adjusted by tilting the melting chamber, ensuring the degree of superheating of the molten steel, and reducing the power consumption equivalent to that of the prior art 2. Can be achieved.

[0007]

However, Prior Art 2 and Prior Art 3 also have the following problems. That is, in the prior arts 2 and 3, when the cold iron source is continuously supplied from the preheating chamber to the molten metal in the melting chamber, the cold iron source preheated to a high temperature can be constantly melted. Although the power consumption can be reduced, the cold iron source is hung below or below the preheating chamber, and the cold iron source remains in the molten metal despite the space in front of the cold iron source. It may not fall and the melting of the cold iron source may stagnate. This phenomenon does not cause any trouble, but if such a phenomenon occurs, the melting time is prolonged, the temperature of the molten metal is increased, and the stable operation is hindered.

Further, in the prior art 3, the contact area between the cold iron source and the molten metal can be greatly reduced by tilting the melting chamber, but the cold iron source and the molten metal are completely separated. It is not done, therefore, even if the temperature of the molten metal is raised while the melting chamber is tilted, the cold iron source in contact with the molten metal begins to melt, and the temperature of the molten metal cannot be raised sufficiently, or In addition, the amount of molten metal increases due to melting of the cold iron source, the contact area between the cold iron source and the molten metal increases, and only the melting of the cold iron source may proceed without giving a degree of superheat to the molten metal.

The present invention has been made in view of the above circumstances,
The first object is to prevent the cold iron source from being suspended in the preheating chamber when melting the cold iron source using an arc melting facility having a shaft type preheating chamber directly connected to the upper part of the melting chamber. In addition, it is an object of the present invention to provide a melting equipment for a cold iron source capable of constantly performing a stable operation. A second object is to provide an arc melting equipment having a shaft type preheating chamber directly connected to an upper part of the melting chamber. It is an object of the present invention to provide a melting facility and a melting method for a cold iron source capable of giving a sufficient degree of superheat to a molten metal when the cold iron source is melted using the method.

[0010]

According to a first aspect of the present invention, there is provided a melting apparatus for a cold iron source for melting a cold iron source, and a melting chamber for melting the cold iron source, which is directly connected to an upper portion of one side to preheat the cold iron source. Shaft-type preheating chamber, an electrode for arc generation for melting the cold iron source in the melting chamber, and cold iron into the preheating chamber so that the cold iron source is continuously present in the melting chamber and the preheating chamber. It has a cold iron source supply means for continuously or intermittently supplying a source, and a tap hole provided in the melting chamber, and melts the cold iron source in the melting chamber by an arc, and a predetermined amount of molten metal is melted in the melting chamber. A melting facility for a cold iron source that discharges molten metal in a state where a cold iron source is present in the melting chamber and the preheating chamber at the time of accumulation, and the preheating chamber on the side where the cold iron source in the preheating chamber is supplied to the melting chamber. The wall surface extends downward at an angle corresponding to the angle of repose of the cold iron source.

According to a second aspect of the present invention, there is provided a melting apparatus for melting a cold iron source, a melting chamber for melting the cold iron source, and a shaft type preheating chamber directly connected to an upper portion of one side thereof for preheating the cold iron source. When,
An electrode for arc generation for melting the cold iron source in the melting chamber, and the cold iron source to the preheating chamber continuously or intermittently so that the cold iron source is continuously present in the melting chamber and the preheating chamber. Cold iron source supply means for supplying, a tapping section protruding from the melting chamber and having a tap hole, and tilting means for tilting the melting chamber toward the tapping section side, melting the cold iron source in the melting chamber by an arc. Then, when a predetermined amount of molten metal is accumulated in the melting chamber, a melting facility of a cold iron source that discharges the molten metal in a state where a cold iron source is present in the melting chamber and the preheating chamber, and the cold iron source in the preheating chamber is: During melting, the preheating chamber of the melting chamber is provided from one side to the other side, and the tapping section is provided in a direction different from the supply direction of the cold iron source, and the preheating chamber of the melting chamber is provided. When the melting chamber is tilted toward the tapping section, the cold iron source The wall of the preheating chamber on the side where the cold iron source in the preheating chamber is supplied to the melting chamber is spaced apart so as to be able to prevent the cold iron source from flowing into the melting section, and has an angle corresponding to the angle of repose of the cold iron source. And has a downward spread.

[0012] In a third aspect of the present invention, in the first or second aspect of the present invention, the cold iron source melting facility is arranged such that the angle corresponding to the angle of repose of the cold iron source is in the range of 7 to 15 degrees. It is a feature.

According to a fourth aspect of the present invention, there is provided a melting apparatus for melting a cold iron source, a melting chamber for melting the cold iron source, and a shaft type preheating chamber directly connected to an upper portion of one side thereof for preheating the cold iron source. When,
An electrode for arc generation for melting the cold iron source in the melting chamber, and the cold iron source to the preheating chamber continuously or intermittently so that the cold iron source is continuously present in the melting chamber and the preheating chamber. Cold iron source supply means for supplying, a tapping section protruding from the melting chamber and having a tap hole, and tilting means for tilting the melting chamber toward the tapping section side, melting the cold iron source in the melting chamber by an arc. A melting facility for a cold iron source that discharges the molten metal when a predetermined amount of molten metal has accumulated in the melting chamber.The preheating chamber is configured such that when the melting chamber is tilted toward the tapping portion, the cold iron source is removed from the preheating chamber. It is characterized in that it is provided inclining in the direction of tilt of the melting chamber toward the hot water outlet so as to prevent the falling into the melting chamber.

According to a fifth aspect of the present invention, there is provided a cold iron source melting facility according to the fourth aspect, wherein the cold iron source in the preheating chamber is moved from one side where the preheating chamber of the melting chamber is provided during melting to the other side. The hot water supply section is provided in a direction different from the supply direction of the cold iron source.

According to a sixth aspect of the present invention, in the melting facility for a cold iron source according to the fifth aspect, the tapping section is provided in a direction perpendicular to a direction in which the cold iron source is supplied to the melting chamber. It is a feature.

According to a seventh aspect of the present invention, there is provided a method for melting a cold iron source, wherein the cold iron source melting equipment is connected to a melting chamber and a preheating chamber using any one of the fourth to sixth inventions. When the cold iron source in the melting chamber is melted by the arc while continuously or intermittently supplying the cold iron source to the preheating chamber so as to maintain the existing state, when a predetermined amount of molten metal is accumulated in the melting chamber, the preheating is performed. The melting chamber is tilted toward the tapping section until the cold iron source does not fall down from the chamber to the melting chamber, and in this state, the cold iron source in the melting chamber is melted by an arc to raise the temperature of the molten metal, and then the molten metal is discharged. It is characterized by the following.

In the first invention and the second invention, the wall surface of the preheating chamber on the side where the cold iron source in the preheating chamber is supplied to the melting chamber expands downward at an angle corresponding to the angle of repose of the cold iron source. Because of this, it is possible to reduce the hanging of the cold iron source in the preheating chamber and contribute to a stable operation in an arc melting facility having a shaft type preheating chamber directly connected to the melting chamber.

In the fourth aspect of the present invention, the supply of the cold iron source from the preheating chamber to the melting chamber can be temporarily stopped. A high degree of superheat can be provided, troubles caused by a decrease in the temperature of the molten metal can be avoided, and a stable operation can be achieved in an arc melting facility having a shaft-type preheating chamber directly connected to the melting chamber.

[0019]

Embodiments of the present invention will be described below with reference to the accompanying drawings. First, the first object of the present invention, that is, the prevention of hanging a cold iron source on a shelf in a shaft type preheating chamber will be described. FIG. 1 shows a first example of an arc melting apparatus according to the present invention, which can prevent hanging of a shelf in a shaft type preheating chamber.
It is a longitudinal section schematic diagram showing an embodiment.

The DC arc melting equipment 1 includes a cold iron source 1
A melting chamber 2 for arc-melting 8 and a shaft-type preheating chamber 3 directly connected to an upper portion on one side thereof are provided. At the upper end of the preheating chamber 3, a duct 23 connected to a dust collector (not shown) is provided. The melting chamber 2 and the preheating chamber 3 are charged with a cold iron source 18 such as iron scrap or direct reduced iron. Since the preheating chamber 3 is installed on one side of the melting chamber 2, the cold iron source 18 charged in the preheating chamber 3 is directed from the position where the preheating chamber 3 of the melting chamber 2 is installed to the opposite side. Supplied.

Above the preheating chamber 3, there is provided a supply bucket 17 suspended from a traveling carriage 26. From this supply bucket 17, an openable and closable supply port provided above the preheating chamber 3 is provided. Cold iron source 18 in preheating chamber 3 via 22
Is charged. In this case, the charging of the cold iron source 18 from the supply bucket 17 is performed while the cold iron source 18 is in operation.
And the cold iron source 18 is supplied to the preheating chamber 3 continuously or intermittently so as to keep the state of being continuously present in the preheating chamber 3. At this time, the charging of the cold iron source 18 may be performed based on a recipe set in advance based on the operation results, or a sensor capable of detecting the amount of the cold iron source 18 in the preheating chamber 3 is provided. The supply of the cold iron source 18 by the supply bucket 17 may be controlled based on a signal from this sensor.

A furnace wall 5 having a water-cooled structure is disposed above the melting chamber 2, and a furnace lid 6 that can be opened and closed is provided above the furnace wall 5. The upper electrode 8 is vertically inserted into the upper part 2 from above. In addition, a furnace bottom electrode 7 is provided at a position facing the upper electrode 8 at the bottom of the melting chamber 2.
Is provided. Then, the cold iron source 18 is melted by the arc 21 formed by these electrodes, and the molten metal 1 is melted.
It becomes 9. The molten slag 20 is formed on the molten metal 19, and the arc 21 is formed in the molten slag 20.

In the melting chamber 2, an oxygen blowing lance 1 is provided.
2. A carbon material blowing lance 13 is inserted with its tip facing the molten metal surface, oxygen is blown into the melting chamber 2 from the oxygen blowing lance 12, and air or nitrogen is blown from the carbon material blowing lance 13. Using a gas or the like as a carrier gas, a carbon material such as coke, char, coal, charcoal, graphite or the like is blown into the melting chamber 2.

A tap hole 15 is formed at the bottom of a projecting portion 2A provided on a portion of the melting chamber 2 which is different from the side to which the preheating chamber 3 is directly connected, and a door for opening and closing the tap port 15 is provided. 24 are provided. Further, on the side wall of the protruding portion 2A, a slag port 16 whose outlet side is closed by a door 25 is provided. The tap 15 may be provided on the side wall in the same manner as the tap 16. A burner 14 is inserted into the protruding portion 2A from above, so that the temperature of the molten metal 19 to be discharged can be increased. In this case, another heating means such as an arc electrode may be used instead of the burner 14.

The side wall 3A of the preheating chamber 3 on the side where the cold iron source 18 is supplied from the preheating chamber 3 to the melting chamber 2 has a taper that spreads downward. This taper needs to be an angle corresponding to the angle of repose of the cold iron source 18 to be used. If the taper is smaller than the angle of repose, hanging of the cold iron source 18 in the preheating chamber 3 occurs. On the other hand, if the taper is larger than the angle of repose, no hanging of the shelf occurs. A gap is formed between the cold iron source 18 and the packed bed, and high-temperature exhaust gas generated in the melting chamber 2 is exhausted through the gap, so that the preheating effect of the cold iron source 18 is deteriorated. Cold iron source 1
Although the angle of repose of 8 varies depending on the type of the cold iron source 18 to be used, the angle of repose is in a range of approximately 7 degrees to 15 degrees.

By setting the angle of the taper to an angle corresponding to the angle of repose of the cold iron source 18, the hanging on the shelf can be greatly reduced without deteriorating the preheating effect. In order to further reduce the hanging of the shelves, it is preferable that the other side walls of the preheating chamber 3 are similarly tapered.

In melting the cold iron source 18 in the DC arc melting equipment 1 having the above-described structure, first,
A cold iron source 18 is charged into the melting chamber 2 and the preheating chamber 3,
Is present in the melting chamber 2 and the preheating chamber 3 continuously.
Then, in this state, the arc 21 is formed to melt the cold iron source 18.

At this time, oxygen is supplied from the oxygen blowing lance 12 to assist dissolution of the cold iron source 18. When the molten metal 19 accumulates in the melting chamber 2, the carbon material is blown into the molten slag 20 from the carbon material blowing lance 13 to start slag forming operation, and the tip of the upper electrode 8 is buried in the molten slag 20. , Arc 21 is molten slag 20
To be formed within.

Exhaust gas generated by the melting is discharged through the preheating chamber 3 and the duct 23, and the heat of the exhaust gas preheats the cold iron source 18 in the preheating chamber 3. Melting chamber 2
As the cold iron source 18 melts in the cold iron source 1 of the preheating chamber 3,
8 are sequentially supplied to the melting chamber 2, so that the upper end position of the cold iron source 18 in the preheating chamber 3 is lowered. In this case, cold iron source 1
A cold iron source 18 is supplied from the supply bucket 17 to the preheating chamber 3 so as to maintain a state in which the heating chamber 8 is continuously present in the melting chamber 2 and the preheating chamber 3.
Is supplied continuously or intermittently. As a result, a state in which a certain amount or more of scrap is always present in the melting chamber 2 and the preheating chamber 3 is maintained.

As the melting of the cold iron source 18 progresses, a predetermined amount of the molten metal 19, for example, the molten metal 19 for one heat or more, is placed in the melting chamber 2.
When the molten iron 19 accumulates, if necessary, the components of the molten metal 19 are adjusted, and then, while the melting chamber 2 is tilted, the molten iron 19 is discharged while maintaining the state where the cold iron source 18 is continuously present in the melting chamber 2 and the preheating chamber 3. The door 24 closing the gate 15 is opened, and the molten metal 19 for one heat is discharged from the tap 15 to a molten metal holding container (not shown). At the time of tapping, the tap 15 by solidification of the molten metal 19
The molten metal 19 may be heated by the burner 14 in order to prevent blockage of the molten metal.

After the tapping, if necessary, the molten metal 19 is heated and refined in a ladle refining furnace or the like, and then cast by a continuous casting machine or the like. The molten metal 19 is discharged, and if necessary, the molten slag 2
After discharging 0, the melting chamber 2 is returned to a horizontal position, and after filling the filling hole 15 and the discharging hole 16 with sand or mud material, melting of the next heat is started. At the time of tapping, several to several tens of tons of molten metal 19 may be left in the melting chamber 2 to resume the melting of the next heat. By doing so, the initial dissolution is promoted and the dissolution efficiency is improved.

By melting in this way, the preheating chamber 3
The hanging of the cold iron source 18 in the shelves is reduced and stable operation is enabled, and the cold iron sources used in the second and subsequent heats are all preheated, so that the power consumption can be greatly reduced.

The degree of superheat (ΔT) of the molten metal 19 is determined by the dissolution rate (W) of the cold iron source 18 and the contact area (S) between the molten iron 19 and the cold iron source 18 immersed in the molten metal. There is a relationship shown in equation (1). ΔT∝W / S (1)

Therefore, in order to increase the degree of superheat (ΔT), the contact area (S) must be reduced under the condition that the dissolution rate (W), that is, the power supply amount in the melting chamber 2 and the blowing amounts of oxygen and carbon material are constant. It is effective to make it smaller. For this reason, when a predetermined amount of the molten metal 19 has accumulated in the melting chamber 2, the melting chamber 2 is tilted toward the tap hole 15 side using a tilting device (not shown), and the molten metal 19 and the cold iron source 18 are By reducing the contact area (S), the temperature of the molten metal at the time of tapping can be increased.

When the melting chamber 2 is tilted as described above to reduce the contact area between the molten metal 19 and the cold iron source 18, the above-described DC arc melting equipment 1 is used.
In the hot water outlet 15, the cold iron source 1 from the preheating chamber 3 to the melting chamber 2 is used.
8, when the melting chamber 2 is tilted, the cold iron source 18 falls down in the tilting direction and the molten metal 1 is tilted.
It is difficult to make the contact area (S) of the cold iron 9 and the cold iron source 18 sufficiently small.

Hereinafter, another preferred embodiment for solving this problem will be described with reference to FIGS. FIG.
FIG. 3 is a perspective view showing a second embodiment of the arc melting equipment according to the present invention capable of preventing rack hanging in a shaft type preheating chamber, FIG. 3 is a plan view of FIG. 2, and FIG. 4 is an arrow XX ′ of FIG. FIG. 5 is a vertical sectional view taken along the line YY ′ in FIG. 2 and shows a state where the melting chamber is horizontal. FIG. 6 is a vertical sectional view taken along the line YY ′ in FIG.
It is a figure which shows the state where the melting chamber was inclined in the longitudinal cross-sectional view by an arrow.

The DC arc melting equipment 1A includes a melting chamber 2 for arc melting the cold iron source 18 and one side 2 of the melting chamber.
The apparatus includes a shaft-type preheating chamber 3 which is directly connected to the upper part of a and extends upward, and a tapping part 4 provided in the melting chamber 2. At the upper end of the preheating chamber 3, a duct 23 connected to a dust collector (not shown) is provided. A cold iron source 18 is charged into the melting chamber 2 and the preheating chamber 3.

In this DC arc melting apparatus 1A, the cold iron source 18 in the preheating chamber 3 is supplied from the preheating chamber side 2a of the melting chamber 2 to the opposite side 2b.
Is projected from the melting chamber 2 so as to face in a direction orthogonal to the supply direction of the cold iron source 18. The melting chamber 2 can be tilted by a tilting device 9 including a plurality of elevating cylinders 10 so that the tapping part 4 side is lowered.

The portion of the melting chamber 2 where the preheating chamber 3 is provided and the portion where the tapping section 4 is provided are separated by a distance a, and when the melting chamber 2 is tilted toward the tapping section 4 side. The cold iron source 18 is prevented from flowing out to the tapping section 4 by the wall of that portion. In this case, as shown in FIG.
Is preferably longer than the distance of the cold iron source 18 extending at an angle of repose from the preheating chamber 3 to the melting chamber 2. By doing so, it is possible to prevent the cold iron source 18 from flowing out to the tapping section 4 when the melting chamber 2 is tilted toward the tapping section 4 side, and to reduce the contact area between the molten metal 19 and the cold iron source 18. The size can be reliably reduced.

As described above, the side wall 3A of the preheating chamber 3 on the side where the cold iron source 18 is supplied from the preheating chamber 3 to the melting chamber 2 is provided.
Has a taper that extends downward. This taper needs to be an angle corresponding to the angle of repose of the cold iron source 18 to be used. Although the angle of repose of the cold iron source 18 varies depending on the type of the cold iron source 18 to be used, the angle of repose is approximately in a range of 7 degrees to 15 degrees. In order to further reduce the suspension of the cold iron source 18 on the shelf, it is preferable that the other side wall of the preheating chamber 3 is also provided with a similar taper.

A tap 15 is provided at the bottom near the tip of the tap 4.
(See FIG. 5), a door 24 for opening and closing the tap hole 15 is provided, and the exit side of the tap portion 4 is closed with a door 25 on the side surface. Slag port 1
6 are provided. Further, the upper electrode 8 is supported by an electrode tilting device 11, and can be tilted as shown in FIG. In addition, the same parts as those of the arc melting equipment 1 shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

When melting the cold iron source 18 in the DC arc melting equipment 1A configured as described above, first, the cold iron source 18 is charged into the melting chamber 2 and the preheating chamber 3, and the cold iron source 18 It is assumed that the melting chamber 2 and the preheating chamber 3 are continuously present. In this state, an arc 21 is formed to melt the cold iron source 18. At this time, oxygen is supplied from the oxygen blowing lance 12 to assist dissolution of the cold iron source 18.

When the molten metal 19 has accumulated in the melting chamber 2,
A carbon material is blown into the molten slag 20 from the carbon material blowing lance 13 to shift to a slag forming operation, the tip of the upper electrode 8 is buried in the molten slag 20, and an arc 21 is formed in the molten slag 20. I do.

Exhaust gas generated by the melting is discharged through the preheating chamber 3 and the duct 23, and the heat of the exhaust gas preheats the cold iron source 18 in the preheating chamber 3. Melting chamber 2
As the cold iron source 18 melts in the cold iron source 1 of the preheating chamber 3,
8 are sequentially supplied to the melting chamber 2, so that the upper end position of the cold iron source 18 in the preheating chamber 3 is lowered. In this case, cold iron source 1
A cold iron source 18 is supplied from the supply bucket 17 to the preheating chamber 3 so as to maintain a state in which the heating chamber 8 is continuously present in the melting chamber 2 and the preheating chamber 3.
Is supplied continuously or intermittently. As a result, a state in which a certain amount or more of scrap is always present in the melting chamber 2 and the preheating chamber 3 is maintained. The charging of the cold iron source 18 at this time is as follows.
As described above, the processing may be performed based on a recipe set in advance based on the operation results, or the cold iron source 1 in the preheating chamber 3 may be used.
8 is provided with a sensor capable of detecting the quantity of the cold iron source 18 based on the signal from the sensor.
May be controlled.

As the cold iron source 18 melts, the cold iron source 18 and the molten metal 19 coexist in the melting chamber 2 and the temperature of the molten metal 19 is low.
Up to 1550 ° C and only a slight degree of superheating with respect to the solidification temperature of molten steel of 1530 ° C.
Inconveniences such as blockage of No. 5 occur. For this reason, in the present invention, the arc heating is continued by tilting the melting chamber 2 toward the tapping section 4 by the tilting device 9 before tapping as shown in FIG. in this case,
The tapping section 4 is protruded from the melting chamber 2 so as to face in a direction orthogonal to the supply direction of the cold iron source 18 to the melting chamber 2.
In addition, the part of the melting chamber 2 where the preheating chamber 3 is provided and the tapping part 4
Is separated from the portion provided with by the distance a, and the wall of the portion prevents the cold iron source 18 from flowing out to the tapping section 4, so that the molten metal 19 flowing into the tapping section 4 and the cold iron The contact area with the source 18 can be reduced.

Accordingly, the degree of superheating of the molten metal 19 can be increased, and the problem that the temperature of the molten metal 19 discharged is low can be largely avoided. By making the distance a longer than the distance of the cold iron source 18 extending at an angle of repose from the preheating chamber 3 to the melting chamber 2, the flow of the cold iron source 18 into the tapping section 4 is almost completely prevented. And the temperature of the molten metal can be further increased.

When the melting chamber 2 is tilted toward the tapping portion 4, the upper electrode 8 is at the position of the dashed line in FIG. 6 and the arc 21 is not effectively supplied, but the upper electrode 8 is tilted by the electrode tilting device 11. By doing so, the position shown by the solid line in FIG. 6 is reached, and the arc 21 can be effectively supplied to the molten metal 19.

Then, the molten metal 19 is heated by arc heating for a predetermined time.
The appropriate degree of superheat (about 30-100 ° C)
After adjusting the components of the molten metal 19 as necessary, the melting chamber 2 and the preheating chamber 3 are moved while the melting chamber 2 is further tilted toward the tapping section 4 side.
While keeping the state where the cold iron source 18 is continuously present inside,
The door 24 closing the tap hole 15 is opened, and the molten metal 19 for one heat is discharged from the tap port 15 to a molten metal holding container (not shown).

After tapping, if necessary, the molten metal 19 is heated and refined in a ladle refining furnace or the like, and then cast by a continuous casting machine or the like. The molten metal 19 is discharged, and if necessary, the molten slag 2
After draining 0, the melting chamber 2 is returned to a horizontal position by the tilting device 9, and after filling the tap hole 15 and the tap hole 16 with sand or mud material, melting of the next heat is started. At the time of tapping, several tons to several tens of tons of the molten metal 19 may be left in the melting chamber 2 and the melting of the next heat may be resumed. By doing so, the initial dissolution is promoted and the dissolution efficiency is improved.

By melting in this manner, the preheating chamber 3
The hanging of the cold iron source 18 in the shelves is reduced and stable operation is enabled, and the cold iron sources used in the second and subsequent heats are all preheated, so that the power consumption can be greatly reduced. Further, the degree of superheat of the molten metal at the time of tapping can be controlled to an appropriate value, and the temperature of the tap hole 15 due to a decrease in the temperature of the molten metal at the time of tapping can be reduced.
It is possible to avoid operational troubles such as clogging of the vehicle.

Next, the second object of the present invention, that is, an increase in the degree of superheat of the molten metal will be described. 7 is a perspective view showing an example of an embodiment of an arc melting equipment according to the present invention capable of giving a sufficient degree of superheat to a molten metal, FIG. 8 is a plan view of FIG. 7, and FIG. FIG. 10 is a partial vertical sectional view taken along the line XX ′, FIG. 10 is a vertical sectional view taken along the line YY ′ of FIG. 7, and shows a state where the melting chamber is horizontal. FIG. 11 is a view taken along the line YY ′ of FIG. FIG. 5 is a view showing a state in which the melting chamber is tilted in a longitudinal sectional view according to FIG.

The DC arc melting equipment 1B comprises a melting chamber 2 for arc melting the cold iron source 18 and one side 2 of the melting chamber.
The apparatus includes a shaft-type preheating chamber 3 which is directly connected to the upper part of the section a and extends obliquely upward, and a tapping section 4 provided in the melting chamber 2. A dust collector (not shown) is provided at the upper end of the preheating chamber 3.
Is provided with a duct 23 which is connected to. This melting chamber 2
A cold iron source 18 is inserted into the preheating chamber 3.

Above the preheating chamber 3, there is provided a supply bucket 17 suspended from a traveling carriage 26. From this supply bucket 17, an openable and closable supply port provided above the preheating chamber 3 is provided. Cold iron source 18 in preheating chamber 3 via 22
Is charged. In this case, the charging of the cold iron source 18 from the supply bucket 17 is performed while the cold iron source 18 is in operation.
The cold iron source 18 is supplied to the preheating chamber 3 continuously or intermittently so as to maintain the state existing in the preheating chamber 3. At this time, the charging of the cold iron source 18 may be performed based on a recipe set in advance based on the operation results, or a sensor capable of detecting the amount of the cold iron source 18 in the preheating chamber 3 is provided. The supply of the cold iron source 18 by the supply bucket 17 may be controlled based on a signal from this sensor.

The cold iron source 18 in the preheating chamber 3 is supplied in a direction from the preheating chamber side 2a of the melting chamber 2 toward the opposite side 2b. It protrudes from the melting chamber 2 so as to face in a direction perpendicular to the melting chamber 2.
The melting chamber 2 can be tilted by a tilting device 9 including a plurality of elevating cylinders 10 so that the tapping part 4 side is lowered. The tapping section 4 does not need to be installed in a direction perpendicular to the supply direction of the cold iron source 18, but may be in the same direction.

The preheating chamber 3 is installed so as to be tilted in the tilting direction when the melting chamber 2 is tilted to the tapping section 4 side, and the inclination angle is set when the melting chamber 2 is tilted to the tapping section 4 side. The angle must be such that the cold iron source 18 in the preheating chamber 3 does not collapse into the melting chamber 2. In order to prevent the cold iron source 18 in the preheating chamber 3 from falling into the melting chamber 2, as shown in FIG. 11, the preheating chamber on the side that holds the cold iron source 18 when the preheating chamber 3 is tilted. The inclination angle (θ) of the side wall 3 from the vertical direction slightly varies depending on the type of the cold iron source 18 to be used, but it is necessary to be approximately 60 degrees or more from the vertical direction. When the inclination angle of 2 is 15 degrees, the preheating chamber 3 needs to be inclined at least about 45 degrees from the vertical direction in advance. Note that the ZZ ′ line shown in FIG. 11 indicates a vertical line.

A furnace wall 5 having a water-cooled structure is disposed above the melting chamber 2, and a furnace lid 6 that can be opened and closed is provided above the furnace wall 5. The upper electrode 8 is vertically inserted into the upper part 2 from above. In addition, a furnace bottom electrode 7 is provided at a position facing the upper electrode 8 at the bottom of the melting chamber 2.
Is provided. Then, the cold iron source 18 is melted by the arc 21 formed by these electrodes, and the molten metal 1 is melted.
It becomes 9. The molten slag 20 is formed on the molten metal 19, and the arc 21 is formed in the molten slag 20. The upper electrode 8 is supported by an electrode tilting device 11, and can be tilted as shown in FIG.

An oxygen blowing lance 12 and a carbon material blowing lance 13 are inserted into the melting chamber 2 with their ends facing the surface of the molten metal. Oxygen is blown into the melting chamber 2 from the oxygen blowing lance 12, and , Carbon material injection lance 1
From 3, a carbon material such as coke, char, coal, charcoal, graphite, etc. is used as a carrier gas using air or nitrogen gas as a carrier gas.
It is blown in.

At the bottom near the tip of the tapping section 4, a tap 15 is provided.
(See FIG. 10), and a door 24 for opening and closing the tap hole 15 is provided. In addition, hot water 4
A slag port 16 whose exit side is closed by a door 25 is provided on the side surface of the tip portion of the slag.

When melting the cold iron source 18 in the DC arc melting equipment 1B configured as described above, first, the cold iron source 18 is charged into the melting chamber 2 and the preheating chamber 3, and the cold iron source 18 It is assumed that the melting chamber 2 and the preheating chamber 3 are continuously present. In this state, an arc 21 is formed to melt the cold iron source 18. At this time, oxygen is supplied from the oxygen blowing lance 12 to assist dissolution of the cold iron source 18.

When the molten metal 19 has accumulated in the melting chamber 2,
A carbon material is blown into the molten slag 20 from the carbon material blowing lance 13 to shift to a slag forming operation, the tip of the upper electrode 8 is buried in the molten slag 20, and an arc 21 is formed in the molten slag 20. I do.

The exhaust gas generated by the melting is discharged through the preheating chamber 3 and the duct 23, and the heat of the exhaust gas preheats the cold iron source 18 in the preheating chamber 3. Melting chamber 2
As the cold iron source 18 melts in the cold iron source 1 of the preheating chamber 3,
8 are sequentially supplied to the melting chamber 2, so that the upper end position of the cold iron source 18 in the preheating chamber 3 is lowered. In this case, cold iron source 1
A cold iron source 18 is supplied from the supply bucket 17 to the preheating chamber 3 so as to maintain a state in which the heating chamber 8 is continuously present in the melting chamber 2 and the preheating chamber 3.
Is supplied continuously or intermittently. As a result, a state in which a certain amount or more of scrap is always present in the melting chamber 2 and the preheating chamber 3 is maintained.

The cold iron source 18 is melted to some extent,
A predetermined amount of molten metal 19, for example, molten metal 1 for one heat or more.
When 9 accumulates, the melting chamber 2 is tilted toward the tapping section 4 by the tilting device 9 to continue the arc heating. Due to this tilt, the preheating chamber 3 directly connected to the melting chamber 2 is tilted by 60 degrees or more from the vertical direction toward the tapping section 4 side, and the cold iron source 18 does not collapse from the preheating chamber 3 to the melting chamber 2.

Therefore, the molten metal 19 and the cold iron source 18 are substantially separated, and when the cold iron source 18 immersed in the molten metal 19 at the time of tilting is melted by the subsequent heating, the molten metal 1
9 is no longer present, and the molten iron 19 is no longer present.
Can be raised to the target temperature, and the problem that the temperature of the molten metal 19 discharged is low can be avoided.

When the melting chamber 2 is tilted toward the tapping portion 4, the upper electrode 8 is at the position of the dashed line in FIG. 11 and the arc 21 is not effectively supplied, but the upper electrode 8 is tilted by the electrode tilting device 11. By doing so, the position shown by the solid line in FIG. 11 is reached, and the arc 21 can be effectively supplied to the molten metal 19.

Then, arc heating is performed for a certain period of time and the molten metal 19 is heated.
The appropriate degree of superheat (about 30-100 ° C)
After adjusting the components of the molten metal 19 as necessary, the outlet 15 is maintained while the cold iron source 18 is present in the preheating chamber 3.
Is opened, and the molten metal 19 for one heat is discharged from the molten metal outlet 15 into a molten metal holding container (not shown).

After tapping, if necessary, the molten metal 19 is refined in a ladle refining furnace or the like, and then cast by a continuous casting machine or the like. Molten 1
After the molten slag 20 is discharged, if necessary, the melting chamber 2 is returned to a horizontal position by the tilting device 9, and the tap hole 1 is discharged.
After filling the filling sand or the mud material into the slag 5 and the slag port 16, the melting of the next heat is started. At the time of tapping, several to several tens of tons of molten metal 19 may be left in the melting chamber 2 to resume the melting of the next heat. By doing so, the initial dissolution is promoted and the dissolution efficiency is improved.

By melting in this manner, the degree of superheat of the molten metal at the time of tapping can be controlled to an appropriate value, and operational troubles such as blockage of tap hole 15 due to a decrease in the temperature of the molten metal at the time of tapping can be avoided. In addition to this, the cold iron sources used in the second and subsequent heats are all preheated, and the power consumption can be greatly reduced.

In the above description, the case of the DC arc melting equipment has been described. However, the present invention can be applied to the AC arc melting equipment without any hindrance. Needless to say, this does not hinder the present invention.

[0069]

[Embodiment 1] Embodiment 1 of the arc melting equipment shown in FIG. 1 will be described. The downward spread angle of the melting chamber (diameter: 7.2 m, height 4 m) and the side wall on the melting chamber side is 10
In the melting room and the preheating room of the DC arc melting equipment directly connected to the preheating room (5 mW x 3 mD),
50 tons were charged, and an arc was formed in a melting chamber with a 28-inch graphite electrode at a maximum power supply capacity of 650 V and 115 kA to melt iron scrap. Further, the acid was fed from an oxygen blowing lance at an amount of 6000 Nm ³ / hr. When molten steel had accumulated in the melting chamber, coke was blown into the slag at 80 kg / min, and the operation was shifted to a slag forming operation, and the tip of a graphite electrode was buried in the forming slag. The voltage and current at this time are 400 V, 90 k
A was set. When the iron scrap in the preheating chamber descends due to the melting of the iron scrap in the melting chamber, iron scrap is supplied from the upper part of the preheating chamber via a supply bucket, and the height of the iron scrap in the preheating chamber is made constant. Held.

As described above, the melting is advanced in a state where the iron scrap is continuously present in the melting chamber and the preheating chamber. When 180 tons of molten steel is generated in the melting chamber, 60 tons are left in the melting chamber and 1 ton is left. 120 tons of molten steel for the heat was poured into the ladle from the tap. The temperature of molten steel at the time of tapping is 156
The temperature was 0 ° C., and the C concentration in the molten steel was 0.1%. The molten steel near the tap was heated by an oxygen-oil burner.

After the tapping of 120 tons, the slag forming operation was performed while supplying acid and coke, and the melting was continued. When the amount of molten steel in the melting chamber reached 180 tons, the tapping of 120 tons was repeated. As a result, the oxygen blowing rate was 33 Nm ³ / t, and the basic unit of coke was 26 k.
Under the operating conditions of g / t, the average time from tapping to 120 tons of molten steel is about 40 minutes, and the power consumption is 175k.
Wh / t. The temperature of the molten steel of 120 tons was raised to 1620 ° C. by a ladle refining furnace (LF), and a billet having a cross section of 175 × 175 mm was produced by continuous casting. The average power consumption of LF is 60 kWh / t on average.
Met.

On the other hand, iron scrap was produced in the same manner as in Example 1 using the same DC arc melting equipment as in Example 1 except that the downward spread angle of the side wall of the preheating chamber on the melting chamber side was 5 degrees. After melting (Comparative Example 1), the unit power consumption and the frequency of occurrence of hanging iron shelves were compared between Example 1 and Comparative Example 1.

Table 1 shows the results of the unit power consumption, and FIG. 12 shows the frequency of trouble occurrence during operation. As shown in Table 1,
As for the power consumption unit, the same result was obtained in Example 1 and Comparative Example 1. However, as shown in FIG. 12, in Example 1, mechanical shelving hardly occurred in the preheating chamber. In some cases, mechanical shelving occurred in the lower part of the preheating chamber, which hindered stable operation.

[0074]

[Table 1]

[Embodiment 2] Embodiment 2 in the arc melting equipment shown in FIGS. 2 to 6 will be described. Melting chamber (length:
8.5 m, width: 3 m, height: 4 m) and a preheating chamber (3.5 mW × 3) in which the downward spread angle of the side wall on the melting chamber side is 10 degrees.
150 tons of iron scrap was charged into the melting chamber and the preheating chamber of the DC arc melting equipment directly connected to mD), and a maximum of 600 V was applied by a 28-inch graphite electrode in the melting chamber.
An arc was formed with a power capacity of 100 kA to melt the iron scrap. In addition, 6000Nm from oxygen blowing lance
^The acid was fed in an amount of ³ / hr. When molten steel had accumulated in the melting chamber, coke was blown into the slag at a rate of 80 kg / min to start slag forming operation, and the tip of the graphite electrode was buried in the forming slag. The voltage at this time was set to 400V. If the iron scrap in the preheating chamber descends as the iron scrap melts in the melting chamber,
Iron scrap was supplied from the upper part of the preheating chamber via a supply bucket, and the height of the iron scrap in the preheating chamber was maintained at a constant height.

As described above, the melting is advanced in a state where the iron scrap is continuously present in the melting chamber and the preheating chamber, and when the molten steel is sufficiently generated, the melting chamber is tilted by 15 degrees to the tapping part side to melt the molten steel. When the molten steel is heated and heated by reducing the contact area between the steel and the scrap, when the molten steel of 180 tons is generated in the melting chamber, the melting chamber is further tilted, and 60 tons are left in the melting chamber, and the heat is left for one heat. 120 tons of molten steel was poured into the ladle from the tap hole. The temperature of molten steel at the time of tapping is 1575 ° C
And the C concentration in the molten steel was 0.1%.

After the 120 tons of hot water was discharged, the melting chamber was returned to its original horizontal state, and slag forming operation was performed while supplying acid and coke to continue melting. When sufficient molten steel was generated, the melting chamber was tilted again. The molten steel is heated to raise the temperature, and when the amount of molten steel in the melting chamber reaches 180 tons again, 12
Repeated tapping of 0 tons. As a result, the amount of oxygen blown was 33 Nm ³ / t, and the basic unit of coke was 26 kg /
Under the operating conditions of t, the average time from tapping of 120 tons of molten steel to tapping is about 40 minutes, and the power consumption is 187 kWh.
/ T.

The temperature of the discharged 120 tons of molten steel was raised to 1620 ° C. by a ladle refining furnace (LF), and a billet having a cross section of 175 × 175 mm was produced by continuous casting. The average power consumption of LF was 45 kWh / t.

On the other hand, iron scrap was produced in the same manner as in Example 2 using the same DC arc melting equipment as in Example 2 except that the downward spread angle of the side wall of the preheating chamber on the melting chamber side was 5 degrees. After melting (Comparative Example 2), the unit power consumption and the frequency of occurrence of hanging iron shelves were compared between Example 2 and Comparative Example 2.

Table 2 shows the results of the unit power consumption, and FIG. 13 shows the frequency of trouble occurrence during operation. As shown in Table 2,
As for the power consumption unit, the same results were obtained in Example 2 and Comparative Example 2. However, as shown in FIG. 13, in Example 2, mechanical shelving hardly occurred in the preheating chamber. In some cases, mechanical shelving occurred in the lower part of the preheating chamber, which hindered stable operation.

[0081]

[Table 2]

[Third Embodiment] A third embodiment in the arc melting equipment shown in FIGS. 7 to 11 will be described. Melting chamber (length:
8.5m, width: 3m, height: 4m) and a preheating chamber (3mW x 3mD) inclined 45 degrees in the direction of tilt of the tapping part.
150 tons of iron scrap were charged, and an arc was formed in a melting chamber with a 28-inch graphite electrode at a maximum power supply capacity of 600 V and 100 kA to melt the iron scrap.
Further, the acid was fed from an oxygen blowing lance at an amount of 6000 Nm ³ / hr. When molten steel accumulates in the melting chamber, 8
Coke was blown into the slag at 0 kg / min to start slag forming operation, and the tip of the graphite electrode was buried in the forming slag. The voltage at this time is 400
V was set. When the iron scrap in the preheating chamber descends due to the melting of the iron scrap in the melting chamber, iron scrap is supplied from the upper part of the preheating chamber via a supply bucket, and the height of the iron scrap in the preheating chamber is made constant. Held.

As described above, the melting is advanced in a state where the iron scrap is continuously present in the melting chamber and the preheating chamber, and when the molten steel is sufficiently generated, the melting chamber is tilted by 15 degrees to the tapping part side, and the preheating is performed. The steel scrap in the melting chamber was completely melted and the molten steel was heated to prevent the steel scrap from falling from the chamber to the melting chamber, so that the molten steel had a sufficient degree of superheat. After thus producing 180 tons of molten steel in the melting chamber,
With 60 tons left in the melting chamber, 120 tons of molten steel for one heat was poured from the tap into the ladle. The temperature of the molten steel at the time of tapping was 1600 ° C., and the C concentration in the molten steel was 0.1%.

After the 120 tons of hot water was discharged, the melting chamber was returned to its original horizontal state, iron scrap in the preheating chamber was supplied into the melting chamber, and slag forming operation was performed again while performing acid feeding and coke blowing to continue melting. When the molten steel is sufficiently generated, the melting chamber is tilted again to the tapping side to prevent collapse of the iron scrap from the preheating chamber to the melting chamber, dissolve all the iron scrap in the melting chamber, and raise the temperature of the molten steel. The molten steel was allowed to have a sufficient degree of superheat, and tapping of 120 tons was repeated. As a result, the oxygen blowing rate was 33 Nm ³
/ T, operating conditions of coke unit consumption of 26 kg / t, 1
The average time from tapping 20 tons of molten steel to tapping is about 40
In a minute, the power consumption was 200 kWh / t.

The temperature of the molten steel of 120 tons was raised to 1620 ° C. by a ladle refining furnace (LF), and a billet having a cross section of 175 × 175 mm was produced by continuous casting. The average power consumption of LF was 35 kWh / t. On the other hand, using the same device, without continuously supplying iron scrap,
The power consumption per unit was similarly obtained for Comparative Example 3 in which each of the batches was melted by heating.

Table 3 shows the results. As shown in Table 3, in Example 3 in which the amount of oxygen used was almost the same and the power was continuously supplied, the power consumption was about 120 kWh / t lower than that in Comparative Example 3, and the power consumption required in the LF was reduced. Even when included, the power consumption was as low as about 100 kWh / t.

[0087]

[Table 3]

Example 4 The same melting as in Example 3 was performed using the same DC arc melting equipment as in Example 3, except that the oxygen intensity was 45 Nm ³ / t and the coke intensity was 36 kg / t. Carried out. The results are also shown in Table 3 above. The power consumption in Example 4 was as extremely low as 160 kWh / t, the time from tapping to tapping was about 37 minutes, and molten steel having an average temperature of 1600 ° C could be produced.

[0089]

According to the present invention, in a melting operation of a cold iron source using an arc melting apparatus having a shaft type preheating chamber directly connected to a melting chamber, the power consumption is extremely low.
In addition, it is possible to perform a stable operation in which operation troubles caused by hanging a cold iron source on a shelf or lowering the molten metal temperature are prevented.
An industrially beneficial effect is provided.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view showing a first embodiment of an arc melting equipment capable of preventing hanging from a shelf according to the present invention.

FIG. 2 is a perspective view showing a second embodiment of the arc melting equipment capable of preventing hanging on a shelf according to the present invention.

FIG. 3 is a plan view of FIG. 2;

FIG. 4 is a vertical sectional view taken along the line X-X ′ in FIG. 2;

FIG. 5 is a vertical sectional view taken along the line YY ′ of FIG. 2, showing a horizontal state of the melting chamber.

6 is a longitudinal sectional view taken along the line YY ′ of FIG. 2 and shows a state where the melting chamber is tilted.

FIG. 7 is a perspective view showing an example of an embodiment of an arc melting facility capable of imparting a sufficient degree of superheat according to the present invention.

FIG. 8 is a plan view of FIG. 7;

FIG. 9 is a partial longitudinal sectional view taken along line XX ′ of FIG. 7;

FIG. 10 is a vertical sectional view taken along the line YY ′ of FIG. 7, showing a state where the melting chamber is horizontal.

11 is a longitudinal sectional view taken along the line YY ′ of FIG. 7, showing a state in which the melting chamber is tilted.

FIG. 12 is a diagram showing a trouble occurrence frequency during operation in the first embodiment.

FIG. 13 is a diagram showing a trouble occurrence frequency during operation in the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 DC arc melting equipment 1A DC arc melting equipment 1B DC arc melting equipment 2 Melting room 3 Preheating chamber 4 Hot water outlet 7 Furnace bottom electrode 8 Upper electrode 9 Tilt device 11 Electrode tilt device 15 Tap hole 16 Outlet 17 Supply Bucket 18 Cold iron source 19 Molten metal 20 Slag 21 Arc

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) F27D 17/00 101 F27D 17/00 101G 4K056 // C21B 11/10 C21B 11/10 13/12 13/12 (72) Inventor Tsuyoshi Nakayama 1-2-1, Marunouchi, Chiyoda-ku, Tokyo F-term (reference) 4K001 AA10 BA22 DA05 FA10 FA14 GA16 GB10 4K012 CA09 4K013 CD02 CD08 CF12 4K014 CB01 CB07 CC05 CD07 CD13 4K045 AA04 BA02 DA07 RA01 RA11 RB02 RB22 4K056 AA05 BA01 BA02 BA06 BB08 CA02 DA02 DA33

Claims (7)

[Claims] 1. A melting chamber for melting a cold iron source, a shaft-type preheating chamber directly connected to an upper portion of one side thereof for preheating the cold iron source, and melting the cold iron source in the melting chamber. An electrode for arc generation, and a cold iron source supply means for continuously or intermittently supplying the cold iron source to the preheating chamber so as to keep the cold iron source continuously present in the melting chamber and the preheating chamber, A state where the cold iron source in the melting chamber is melted by an arc, and a predetermined amount of molten metal is accumulated in the melting chamber, and the cold iron source is present in the melting chamber and the preheating chamber having a tap hole provided in the melting chamber. This is a melting facility for a cold iron source that discharges molten metal at a temperature where the wall of the preheating chamber on the side where the cold iron source in the preheating chamber is supplied to the melting chamber extends downward at an angle equivalent to the repose angle of the cold iron source. A melting facility for a cold iron source, comprising: 2. A melting chamber for melting a cold iron source, a shaft type preheating chamber directly connected to an upper portion of one side thereof for preheating the cold iron source, and melting the cold iron source in the melting chamber. An electrode for arc generation, and a cold iron source supply means for continuously or intermittently supplying the cold iron source to the preheating chamber so as to keep the cold iron source continuously present in the melting chamber and the preheating chamber, It has a tapping section protruding from the melting chamber and having a tap hole, and a tilting means for tilting the melting chamber toward the tapping section, melting a cold iron source in the melting chamber by an arc, and supplying a predetermined amount of molten metal to the melting chamber. Is a melting facility of a cold iron source that discharges molten metal in a state where a cold iron source is present in the melting chamber and the preheating chamber at the time of accumulation of the cold iron source in the preheating chamber. It is supplied from one side provided to the other side, and the tapping section is provided in a direction different from the supply direction of the cold iron source. In addition, the part of the melting chamber where the preheating chamber is provided and the part where the tapping section is provided can prevent the cold iron source from flowing out to the tapping section when the melting chamber is tilted toward the tapping section. The walls of the preheating chamber that are spaced apart from each other and on the side where the cold iron source in the preheating chamber is supplied to the melting chamber have a downward spread at an angle corresponding to the angle of repose of the cold iron source. Melting equipment for cold iron sources. 3. An angle corresponding to the angle of repose of the cold iron source is 7
The melting equipment for a cold iron source according to claim 1, wherein the melting temperature is in a range of 15 degrees to 15 degrees. 4. A melting chamber for melting a cold iron source, a shaft-type preheating chamber directly connected to an upper portion of one side thereof for preheating the cold iron source, and melting the cold iron source in the melting chamber. An electrode for arc generation, and a cold iron source supply means for continuously or intermittently supplying the cold iron source to the preheating chamber so as to keep the cold iron source continuously present in the melting chamber and the preheating chamber, It has a tapping section protruding from the melting chamber and having a tap hole, and a tilting means for tilting the melting chamber toward the tapping section, melting a cold iron source in the melting chamber by an arc, and melting a predetermined amount of molten metal into the melting chamber. Is a melting facility for a cold iron source that discharges molten metal at the time of accumulation of the molten metal, and the preheating chamber can prevent the cold iron source from collapsing from the preheating chamber to the melting chamber when the melting chamber is tilted toward the tapping part. Characterized in that the cold iron source is provided so as to be inclined in the direction of tilt of the melting chamber toward the tapping portion as possible. Melting equipment. 5. The cold iron source in the preheating chamber is supplied from one side, in which the preheating chamber of the melting chamber is provided, to the other side during melting, and the tapping part is connected to the supply direction of the cold iron source. The cold iron source melting facility according to claim 4, wherein are provided in different directions. 6. The melting facility for a cold iron source according to claim 5, wherein the tapping section is provided in a direction orthogonal to a direction in which the cold iron source is supplied to the melting chamber. 7. A cooling apparatus for melting a cold iron source according to any one of claims 4 to 6, wherein the cold iron source is cooled to a preheating chamber so as to maintain a state in which the cold iron source continuously exists in the melting chamber and the preheating chamber. While the iron source is continuously or intermittently supplied, the cold iron source in the melting chamber is melted by an arc, and when a predetermined amount of molten metal is accumulated in the melting chamber,
The melting chamber is tilted to the tapping side until the cold iron source does not fall down from the preheating chamber to the melting chamber, and in this state the cold iron source in the melting chamber is melted by an arc to raise the temperature of the molten metal. A method for dissolving a cold iron source.