JPH0548071Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for discharging molten material from the spout of a melting furnace formed at the bottom of the melting furnace. This relates to the structure of a device that closes an outlet.

[Prior Art] Generally known metal melting furnaces include arc furnaces, which mainly melt and refine scrap, and converters, which refine hot metal tapped in blast furnaces.

In recent years, a bottom tapping type arc furnace 5 as shown in FIG. 2 has been adopted. As shown in the figure, the bottom tapping type arc furnace 5 similarly has a furnace body 2 and a furnace lid 3 made of steel plates and refractory bricks, and a part of the spherical furnace bottom 6 is radially outward. A tapping section 7 is provided extending from the tap section 7, and a tap hole 8 is formed in the tapping section 7. This hot water outlet 8 is provided with an opening/closing gate 9 for closing it from below, and a ladle 10 is installed directly below the opening/closing gate 9. This bottom tapping type arc furnace 5 requires only a small inclination angle of the furnace body 2 due to the tilting device 11 provided on the furnace body 2, and since steel is tapped from the furnace bottom 2, slag does not get mixed into the ladle 11. It's difficult.

The opening/closing gate 9 that closes the hot water outlet 8 includes:
Rotating flapper gate 1 as shown in Figure 3
2 and a horizontally movable slide gate 13 as shown in FIG. The structure of the hot water outlet 8 is such that a cylindrical through hole is formed by penetrating the steel plate and refractory bricks of the hearth bottom 2, and a graphite block 14 is placed inside the hole so that the opening shape is cylindrical. Ta.

The tap 8 was closed by filling the tap 8 with sand 15 from inside the furnace after closing the opening/closing gate 9.

In tapping the bottom tapping type arc furnace 5 with the tap 8 closed in this way, the sand 15 is removed from below the tap 8 and the molten steel is discharged after the opening/closing gate 9 is opened.

[Problems to be solved by the invention] By the way, the structure of the conventional melting furnace has the following problems.

During tapping, the graphite block 14 installed in the tap hole 8 is worn out due to erosion, oxidation, etc.
There was a problem in that the operation of the furnace 5 had to be stopped while this was replaced.

Further, after the opening/closing gate 9 is closed, the sand 15 is filled into the spout 8 from inside the furnace, so there is a problem that a sand 15 filling machine (not shown) is required.

Furthermore, there was a problem that it took time to fill the sand 15.

In particular, in the case of a melting furnace such as a converter (not shown) which is vertical and has thick bricks at the bottom, there is a problem in that it is difficult to fill the sand 15 from inside the furnace.

In view of the above-mentioned problems, the present invention can prevent wear and tear of the graphite block installed in the spout provided at the bottom of the furnace, and also makes it possible to easily fill the spout with sand in a short time. Another object of the present invention is to provide a bottom discharge device that can easily and reliably discharge the molten material from the bottom of a melting furnace.

[Means for Solving the Problem] In order to achieve the above object, in the bottom discharge device for a melting furnace of the present invention, the structure of the spout is such that the inside of the spout formed at the bottom of the melting furnace is opened. It is made of graphite or a refractory block so that it has a truncated conical shape, and an inner cylinder in the shape of a truncated conical cylinder made of graphite or a refractory is removably attached to the spout. It is.

The inner cylinder is filled with sand and is removably installed in the spout, which is lined with graphite or refractory blocks.

[Operation] A cylindrical through hole is formed in the bottom of the melting furnace, and a block made of graphite or refractory is formed on the inner wall thereof so that the opening shape is a truncated cone. Then, an inner cylinder in the shape of a truncated conical cylinder is formed of graphite or refractory material and is dimensioned to fit into the spout formed of graphite or refractory block. By removably installing the inner cylinder formed in this way in the spout which is equipped with the above-mentioned graphite or refractory block, the inner cylinder is free from wear and tear due to melting and oxidation when discharging the melt. The graphite or refractory block forming the spout will be protected. Since the worn inner cylinder is removably provided, it can be replaced with a new inner cylinder in the next process.

In addition, because this inner cylinder is filled with sand in advance and inserted into the spout that is lined with graphite or refractory material, the spout can be easily and reliably blocked in a short time after discharging the molten material. The water will be filled into the spout.

[Example] The structure of the spout of the melting furnace of the present invention will be described below in detail based on the accompanying drawings.

As shown in FIG. 1, the furnace body of the melting furnace 20 has a steel plate 2
1 and firebrick 22. 1st
The figure shows the main part of the furnace bottom 23, and a tap hole 24 is formed in the furnace bottom 23 for discharging the molten material contained in the furnace. The hot water outlet 24 is formed by inserting a graphite block 2 into a cylindrical through hole 25 that penetrates the steel plate 21 and the firebrick 22 so that the opening shape is a truncated cone.
6 inside. That is, the inner diameter of the graphite block 26 housed in the spout 24 is formed to gradually increase in diameter from the top to the bottom, and the relationship is such that the inner diameter d at the top<the inner diameter D at the bottom.

Further, an inner cylinder 27 made of graphite and shaped like a truncated conical cylinder is detachably provided in the hot water spout 24 which is housed inside the graphite block 26. That is, the outer diameter of the inner cylinder 27 is formed to gradually increase from the upper part to the lower part. The inner diameter of the inner cylinder 27 may be such that the inner space has a truncated conical shape or a cylindrical shape. The outer peripheral shape and dimensions of this inner cylinder 27 are as follows:
Hot water outlet 24 inside the graphite block 26
The shape and dimensions of the opening are approximately the same as those of the graphite block 26, and the inner cylinder 27 is formed to be inserted into the graphite block 26. That is, the outer diameter of the top of the inner cylinder 27 = d
It is formed so that the outer diameter of the lowermost part=D. Further, the length of the graphite block 26 and the length of the inner cylinder 27 are formed to be approximately equal. Further, an engaging portion 28 such as a threaded portion for engaging with each other is formed at the lower end of the graphite block 26 and the lower end of the inner tube 27 so that the inner tube 26 can be detachably attached to the graphite block 26. ing.

Next, the operation of the above embodiment will be described.

Through hole 25 penetrated through bottom 23 of melting furnace 20
The opening of the graphite block 26 installed in the inner wall of the graphite block 26 has a truncated conical shape. The inner cylinder 27 made of graphite has a truncated conical shape. Further, since the outer peripheral shape and dimensions of the inner tube 27 are formed to be approximately equal to the opening shape and dimensions of the graphite block 26, the inner tube 27 can be inserted into the graphite block 26. Furthermore,
At the lower end of the graphite block 26 and at the lower end of the inner cylinder 27, engaging portions 28 that engage with each other are formed, so that these are detachably provided. In this way, by installing the inner tube 27 made of graphite inside the graphite block 26, the inner tube 27 can be prevented from being worn out first due to melting damage, oxidation, etc. when the molten steel contained in the furnace is tapped. As a result, the graphite block 26 is protected from wear and tear. Since the worn inner cylinder 27 is detachably provided, it can be replaced with a new inner cylinder 27 in the next process. Therefore, a plurality of inner cylinders 27 having the same shape and size may be manufactured in advance.

Further, the inner cylinder 27 is filled with sand 29 in advance on the ground. The inner cylinder 27 filled with this sand 29 is placed on a lifting device 30 provided below the tap 24 and inserted into the graphite block 26. This lifting device 3
0 is formed by, for example, a hydraulic cylinder.
The inner cylinder 27 filled with this sand 29 is
8, it is kept as it is.
In other words, since the inner cylinder 27 has already been filled with sand 29, the same state as when sand 29 is filled into the inner cylinder 27 from inside the furnace can be obtained.

By filling the sand 29 into the inner cylinder 27 in this way, the spout 24 can be easily and reliably filled with the sand 29 in a short time.

In particular, for converters with thick refractory bricks at the bottom of the furnace, the structure of the spout of the present invention is adopted, and the inner cylinder 27 filled with sand 29 allows sand to flow into the spout. By filling the container with , the plugging operation can be performed more efficiently.

To tap the melting furnace 20 which is closed using the spout structure of the present invention, first place a ladle under the spout 24, open the opening/closing gate 31,
This is done in the same manner as in the conventional method, by removing the sand 29 from the spout 24 from below and discharging the molten steel into the ladle.

[Effects of the invention] In summary, the present invention provides the following excellent effects.

In the structure of the spout of the melting furnace according to the first aspect, it is possible to prevent the graphite block installed in the spout from being worn out.

In the structure of the spout of the melting furnace according to claim 2, the spout can be easily filled with sand in a short time.

Furthermore, compared to the conventional structure in which sand is filled from inside the furnace to the spout, sand can be filled more reliably.

Furthermore, even in melting furnaces such as converters that have thick firebricks at the bottom of the furnace, or melting furnaces that have a structure in which the bottom of the furnace extends to the side to form a tapping port, where it is difficult to fill the tapping port with sand from inside the furnace, it is possible to fill the sand very easily.

Furthermore, since sand can be filled into the inner cylinder on the ground, a sand filling machine is not required.

Furthermore, during the melting and refining process, sand can be filled in advance into the inner cylinder for the next process.

[Brief description of the drawings]

Fig. 1 is a schematic diagram of the main parts showing the structure of the tap outlet of the melting furnace of the present invention, Fig. 2 is a schematic diagram showing the bottom tapping type arc furnace, and Figs. 3 and 4 are the conventional structure. It is a principal part schematic diagram for explanation. In the figure, 20 is a melting furnace, 23 is a furnace bottom, 24 is a spout, 26 is a graphite block, 27 is an inner cylinder, and 29 is sand.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. In a bottom discharge device for discharging molten material from a spout formed at the bottom of a melting furnace, the spout is made of graphite or refractory and has a truncated conical opening shape. A molten material bottom discharge device for a melting furnace, characterized in that it is formed of an internal block and that an inner cylinder in the shape of a truncated conical cylinder made of graphite or refractory is detachably provided at the spout. . 2. The molten material bottom discharge device for a melting furnace according to claim 1, wherein the inner cylinder is filled with sand.