JPS642874B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a furnace body structure for an arc furnace for steelmaking, which makes it possible to extend the furnace repair cycle time and shorten the furnace repair time, thereby improving productivity.

The conventional arc furnace furnace body for steelmaking is shown in Figures 1 to 2.
As shown in Figure A, the furnace is mainly composed of a steel shell, a refractory material housed within the steel shell, and a furnace support supporting the steel shell. The above-mentioned iron skin is formed from a single welded steel plate. The refractory material is made by compression molding magnesia powder.

The refractory material of this steelmaking arc furnace body is eroded during operation. As shown in FIG. Pipe 1 for pressurizing material
The filling method has been carried out by a worker through the work door opening 105 via the 06, but this method has the following drawbacks.

(1) The work environment is poor due to the high temperature work, and the work is short-term, making it hard work for the workers, causing great fatigue, and making complete repairs difficult.

(2) In particular, as shown in FIG.
The repair of the blind spot 108 of No. 6 becomes insufficient, which causes an unexpected accident in which the molten steel 103 flows out of the furnace.

(3) It is necessary to incorporate the furnace repair time for the above-mentioned hot repair into the operating time (one cycle from tapping to the next tapping), and this time is uneven.

In the figure, 101 is an iron shell, 102 is a fireproof material,
104 is a slag, and 109 is a refractory material melted portion.

Incidentally, in recent years, the upper part of the furnace wall of an arc furnace body for steelmaking has been formed into a water-cooled block structure in order to prevent melting damage. The lower part of the furnace wall is still made of refractory material, but insulating material has been installed along the steel shell to improve thermal efficiency.

The present invention solves the above-mentioned drawbacks of the conventional furnace body structure, and provides a steelmaking arc furnace furnace body structure that enables extension of the furnace repair cycle time and shortening of the furnace repair time, thereby improving productivity. The gist of this is that in a steelmaking arc furnace furnace body structure in which the furnace wall is a water-cooled structure, a part or most of the furnace shell at the bottom of the furnace wall corresponding to the vicinity of the slag layer is shaped into the furnace shell shape. A furnace body for an arc furnace for steelmaking, characterized in that it has an overhanging structure that overhangs outward along the sides, and an opening for charging a repair refractory material between the upper part of the overhanging structure and the furnace wall of the water-cooled structure. It's in the structure.

Next, the present invention will be explained with reference to the drawings.

FIG. 3 shows a cross-sectional view of one embodiment of the present invention.

In the steelmaking arc furnace body structure of this embodiment, the upper part of the furnace wall is formed of a water-cooled block structure 4, and
The lower part of the furnace wall is formed of a refractory material 6 made of compressed magnesia powder, and is covered with an iron shell 1.
The furnace side wall shell 3 is welded and fixed to a furnace body support (not shown), and a part or most of the furnace shell corresponding to the vicinity of the slag layer 8 at the bottom is shaped like the furnace shell, that is, along the furnace side wall shell 3. An overhanging structure 1a extends outward and is welded and fixed to the furnace support column (not shown).The upper part of the overhanging structure 1a is open, and heat of magnesia powder, etc. Opening 1 for supplying refractory material 2 for temporary repair
This is a configuration that causes 0 to be formed.

FIG. 3 shows the overhang structure 1a and the opening 1.
0 is a cross-sectional view of the portion where 0 is formed, and the other portions, the upper furnace wall of the water-cooled block 4 and the lower furnace wall of the refractory material 6, are integrally formed by the iron shell 1 and the furnace body support.

In the refractory material 6 made of compacted magnesia powder, a heat insulating material (not shown) for improving the thermal efficiency of the furnace body is installed along the shape of the steel shell 1, as in the conventional case, and the overhang structure 1a is The insulation material is not overhanging but is formed by standing straight up in the section.

In this configuration, the lower part of the overhanging structure 1a is integrated with the furnace bottom shell 1 and forms the outer shell of the furnace body 5. This overhanging structure 1a is made of steel plate or has a water-cooled block structure. It goes without saying that the water cooling block 4 is placed at a location where it does not come into contact with the molten steel 7 or the slag layer 8, that is, at a position above the level of the slag layer 8.

The refractory material eroded portion 11 shown in FIG. 3 shows a state where the eroded damage is in progress. As this progresses, the refractory material 6 and the heat insulating material of the overhang structure 1a collapse, and a through hole opens in the refractory material 6 at the opening 10. Even in this state, since the opening 10 is formed above the level of the slag layer 8, slag and molten metal will not leak to the outside. Then, by refilling the hot repair refractory material 2 such as magnesia powder through the through hole,
The above-mentioned through hole is closed as an emergency measure even if the repair shape is not completed during operation of the furnace. The filled hot repair refractory material 2 is fired by the heat of the molten metal.

As shown in the drawings, the present invention further provides that a thermocouple 9 connected to an alarm device (not shown) is attached to a portion of the overhanging structure 1a, and the melting loss of the refractory material near the slag line 8a progresses to a certain thickness. When this happens, an alarm is issued based on the side temperature detected by the thermocouple 9.

This is because if the above-mentioned heat insulating material is damaged, the temperature will rise significantly. When this alarm is issued, even before the through hole is opened in the refractory material 6 of the opening 10, the refractory material 6 can be broken from outside the furnace to forcibly form the through hole. Similarly, repair using hot repair refractory material 2 can be performed.

This makes it possible to perform furnace repair work effectively and more reliably prevent unexpected accidents from occurring.

With this configuration, the hot repair refractory material 2 can be supplied from the outside through the opening 10 as needed without any restrictions on operation, and can be filled into the heavily eroded portion 11 near the slag line 8a. , it is possible to shorten furnace repair work time, thereby improving productivity.

The above-mentioned melting loss near the slag layer 8 is caused by the refractory material being mainly eroded by the slag 8, and the above-mentioned melting damage portion 1
It will be in a state like 1. Since this condition occurs every time the steel is melted, it must be corrected by furnace repair work after steel is tapped. Conventionally, this furnace repair work was difficult to repair, and the work was time consuming and uneven. As a result, the time from one tapping to the next tapping was uneven, which greatly hindered productivity improvement. The invention was able to solve this problem by adopting the above configuration.

In the case of the steelmaking arc furnace furnace body structure of this embodiment, the upper part of the furnace wall, specifically the furnace side wall above the opening 10 of the overhanging structure 1a, is formed of the water-cooled block 4. The inner wall of the upper part of the furnace side wall will not be damaged by sparks from the electrodes. Therefore, since the refractory material 6 below the opening 10 is inevitably damaged, the steelmaking arc furnace furnace body structure of the present invention has an overhanging structure 1a formed at a location where melting damage is likely to occur, such as near the electrode. If you keep it in place, it will be extremely easy to repair.

The effects of the present invention are as follows.

(1) It is possible to shorten the furnace repair time and extend the furnace repair cycle time, thereby improving productivity.

(2) Furnace repairs near the slag line can be easily performed from outside the furnace, resulting in the following effects.

(a) High temperature work is eliminated and the working environment is improved.

(b) Preventive maintenance is possible because the furnace can be repaired while the power is on.

(c) Reliability of reactor modifications is increased and unforeseen accidents are eliminated.

(3) By installing a side heating device connected to an alarm device on the overhanging structure, melting of the refractory material near the slag line can be detected more quickly and furnace repair work can be carried out more effectively. can.

As described above, the present invention provides a steelmaking arc furnace furnace body structure that enables shortening of furnace repair time and extension of furnace repair cycle time, thereby improving productivity, and is extremely useful in steelmaking. It is.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an example of a conventional steelmaking arc furnace body, FIG. 2 is a plan view of the arc furnace body of FIG. 1,
FIG. 2a is a sectional view taken along the line A-A' in FIG. 2, and FIG. 3 is a sectional view of one embodiment of the present invention. In the figure, 1... Furnace bottom shell, 1a... Overhang structure, 2... Repair refractory material, 3... Furnace side wall shell,
4... Water cooling block 5... Furnace body, 6... Refractory material, 7... Molten steel, 8... Slag layer, 8a... Slag line, 9... Thermocouple (temperature measuring device), 101...
...Iron skin, 102...Refractory material, 103... Molten steel, 1
04...Slag, 105...Working door opening,
106...Pumping pipe, 107...Hot repair material pressure feeding tank, 108...Blind area, 109...Refractory material melted part, 110...Steel tapping gutter, 111...Furnace body support, 10...Repair fireproofing Material charging opening, 11...
...Refractory material melted part.

Claims (1)

[Claims] 1. In a steelmaking arc furnace furnace body structure in which the upper part of the furnace wall is formed of a water-cooled structure and the lower part of the furnace wall is formed of a refractory material with a heat insulating material inside, the above-mentioned structure corresponding to the vicinity of the slag layer A part or most of the furnace grain at the bottom of the furnace wall is made into an overhanging structure that extends outward along the shape of the furnace shell, and a repair refractory material is charged between the upper part of the overhanging structure and the furnace wall of the water-cooled structure. A furnace body structure for an arc furnace for steelmaking, characterized by having an opening. 2 In a steelmaking arc furnace furnace body structure in which the upper part of the furnace wall is formed of a water-cooled structure and the lower part of the furnace wall is formed of a refractory material with an internal heat insulating material, the furnace shell of the lower part of the furnace wall corresponding to the vicinity of the slag layer A part or most of the structure is an overhanging structure extending outward along the shape of the furnace shell, and an opening for charging a repair refractory material is provided between the upper part of the overhanging structure and the furnace wall of the water-cooled structure, A steelmaking arc furnace furnace structure, characterized in that a side heating device connected to an alarm device is attached to a portion of the overhanging structure corresponding to the slag line.