JPH03186187A - Electric furnace spout repair method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for repairing a spout (raw material supply chute) of a three-phase L-type electric furnace.

[Prior art] Figure 4 (al, fbl shows an example of spout arrangement in a three-phase L-type electric furnace, (a) is a plan view, lb)
FIG. 1 is a diagram showing the AA cross section of the ta+ diagram. 10 is an electric furnace body, 11 is a furnace lid, 12 is an electrode, 13 is a t-balance holder, 14 is a spout which is a raw material supply chute into the electric furnace, and a large number of spouts are arranged so as to pass through one soybean 11. There is. Each of these spouts has a raw material input pipe 2.
is connected. The raw material input pipes for supplying raw materials to the center of the furnace must be gathered in a very narrow area surrounded by the three electrodes 12, so these multiple raw material input pipes are connected to the central spout 1. collectively connected.

In order to supply raw materials to the electric furnace, the spout and raw material input pipe are always filled with raw materials, and raw materials are automatically supplied in proportion to the decrease in the raw material level in the furnace. Therefore, the raw material level is always maintained constant. However, during long-term operation, there will be damage to the spout due to high heat and wear, and the damage will start from the lower end, and the dimensions of the spout will gradually become shorter. When the length of the spout becomes shorter (hereinafter referred to as reduction), the raw material level becomes
As shown in FIG. 4 1bl, for example, it changes from I-0 to Ll, and increases as the spout is damaged.

If this state is left as it is, there is a risk that the raw material will come into contact with the electrode holder 13.

For this reason, a spout that has been reduced in size to the limit must be restored to its original length. However, a large number of spouts are arranged on the chivalrous hearth, especially the central spout 1.
Since it is arranged in a very narrow area surrounded by the electrode 12, it is extremely difficult to extract it outside the furnace. Therefore, the damaged part cannot be repaired,
The damaged spout was dropped into the furnace and a new spout was installed and updated. Spout replacement is carried out by removing the furnace lid and inserting a new spout from inside the furnace.

[Problems to be Solved by the Invention] In the above-mentioned prior art, there is a problem in that if the spout is damaged and reduced in size, it cannot be repaired and the entire spout must be renewed. Moreover, when updating,
Since a new spout cannot be inserted or removed from the top of the furnace lid, it is essential to remove the furnace lid and insert a new spout from inside the furnace. Furthermore, in this case,
The temperature inside the furnace must drop to a level that allows workers to enter, so the electric furnace must be shut down for a long period of time (usually about a month) to cool the inside of the furnace, and production has to be halted during this time. be done.

The present invention solves the above problems of the prior art and provides a spout repair method for an electric furnace that can repair a damaged spout without requiring a long-term shutdown of the electric furnace and without replacing the spout. purpose.

[Means and effects for solving the problem] In order to achieve the above object, in the present invention, the connection portion between the reduced spout and the raw material input pipe is separated, and the spout is connected to the same length as the reduced length. A short pipe having a diameter is inserted into the connecting portion, and the reduced spout is restored to the length before the reduction.

As a result, the height of the lower end of the reduced spout in the electric furnace becomes the same as the lower end height of the spout before the reduction,
Raw material level becomes normal.

Since this repair work is performed outside the furnace (on the furnace lid), there is no need for cooling and it is only necessary to stop the electric furnace for a short time.

[Example] Hereinafter, as a representative example of the embodiment of the present invention, a method for repairing a central spout, which is extremely difficult to extract from the furnace, will be described.

FIGS. 3A and 3B are diagrams showing the damaged central spout, the FAT diagram is a side view, and the FBL diagram is a plan view.

A plurality of raw material input pipes 2 are connected to the central spout 1, and the inside thereof is divided into a plurality of parts by a partition plate 3, and the raw materials supplied from each raw material input pipe 2 are divided and charged into the furnace. It looks like this. The connecting portion 4 between the central spout 1 and the raw material input pipe 2 is flange-jointed.

5 is the part that has disappeared due to damage, and this central spout 1 is shorter than its original size by a length g.

FIG. 1 shows one embodiment of the present invention, and is a side view of a state in which the central spout has been repaired. Repair the reduced central spout as follows: First, temporarily stop the electric furnace and disconnect the flange at the connection between the central spout 1 and the raw material input pipe 2 provided on the furnace lid.Next, lower the central spout 1 and connect the central spout 1 and the raw material input pipe 2. A flanged short pipe 6 having the same length 1 as the reduced length of the spout is inserted into the connection part with an interval of . This restores the length of the central spout to the length before the reduction.

FIG. 2 is a plan view showing the interposed short tube. A short pipe partition plate 5 is provided in connection with the partition plate provided on the damaged central spout, so that there is no problem in the division of raw material supply.

The above repair can be completed in a few hours. Therefore, stopping the electric furnace only takes a few hours.

[Effects of the Invention] The present invention repairs a damaged spout while it is still attached to the electric furnace without replacing it, and connects a short pipe with the same length as the reduced length to the spout and material input pipe. According to the method of the present invention, which is a method of restoring the spout to its pre-reduced length by interposing the spout at the connection part with the spout, the repair can be completed in a very short time.

Therefore, in contrast to the prior art, which required a period of over a month to shut down the electric furnace for repair, the present invention requires only a few hours to shut down, which greatly contributes to improved productivity.

[Brief explanation of drawings]

Fig. 1 shows an embodiment of the present invention, and is a side view of the central spout after repair, Fig. 2 is a view showing the intervening short pipe, and Fig. 3
The figure shows a damaged central spout, and FIG. 4 shows an example of spout arrangement in a three-phase L-type electric furnace. 1... Central spout, 2... Raw material input pipe, 3...
Partition plate, 4... Connection part, 5... Portion lost due to damage, 6... Short pipe with flange, 7... Partition plate of short pipe, 10... Electric furnace main body, 11...・Heart cover, 12
...electrode, 13...electrode holder, 14...spout.

Claims (1)

[Claims] In a method for repairing a spout of a three-phase electric furnace that has been reduced in size due to damage, the connection between the reduced spout and the raw material input pipe is cut off, and a short pipe having the same length as the reduced length of the spout is installed. A method for repairing a spout of an electric furnace, which comprises interposing the spout in the connecting portion and restoring the reduced spout to its pre-reduced length.