JPS5836047B2 - Continuous steel manufacturing method - Google Patents

Description

[Detailed description of the invention] The present invention moves the furnace body within a set range, and repairs and inspects the refractories in the furnace, supplies raw materials, melts and smelts, and takes out molten steel at a predetermined position. This invention relates to an improvement in a continuous steel manufacturing method in which the electric furnace is moved in the order of each step to carry out the process continuously.

In the conventional steelmaking method, raw materials (such as iron scraps) are put into an electric furnace that is tilted at the same position, a lid is placed on the furnace body, and an electrode is inserted through the lid. After electricity is applied to melt the raw materials and further smelting, the furnace body is tilted to transfer the molten steel into a ladle.The ladle is then transferred to an ingot production plant using a crane, etc., where it is made into the desired ingot. are doing.

Therefore, this method has drawbacks such as poor utilization efficiency of the electric furnace, and moreover, a plurality of mechanisms are required since the furnace body is tilted with the electrodes provided thereon.

The present invention has been made in view of this.

The present invention will be explained below based on examples.

That is, the present invention performs repair and inspection of the refractories in the furnace at a predetermined position within the movement range in which a plurality of electric furnaces are moved in a loop,
In addition, there is a raw material supply position A where raw materials (iron scraps, etc.) are fed into the electric furnace, a position B where the lid is closed for melting and scouring, and a position B where the molten steel is opened and the lid is tilted, and the molten steel is placed in a preheated and waiting ladle. A take-out position C is provided, and by moving the electric furnace between these positions, one step of each of the above steps is completed and the required steel production is performed.

Each of these steps will be explained in detail below.

At the raw material supply position A, the electric furnace 1 is stopped at a position below the hopper that stores a certain amount of raw materials by a moving crane or a belt conveyor, and after inspection and repair of the refractories, the open-top A required amount of raw materials such as iron scraps is supplied into the furnace body, and then the electric furnace is suspended from a crane or the like and transferred to the next process of melting and scouring position B.

The raw material in the electric furnace 1 is preheated to a certain temperature at this person's position, or it is preheated during the transition from position A to position B.

This transition of the electric furnace can also be carried out automatically by installing the electric furnace on a cart with running wheels and introducing a computer that sets the time for stopping each furnace body at each process position.

Next, when the electric furnace 1 reaches the melting/scouring position B, the electrode 3 with a lid connected to a power source is lowered, inserted into the electric furnace, and the lid is closed, followed by energization.

In the initial stage, this current is applied with high power to melt the raw material, and then the power is switched to low power to perform scouring for a certain period of time.

In this manner, after the completion of the refining, the electrodes are pulled up and the electric furnace is suspended and moved to the next molten steel extraction position C using a crane or the like.

A tilting device 5 in which the molten steel melted and refined here is installed in an electric furnace.
The molten steel is tilted with the lid closed through the molten steel outlet 4 to wait at a position below the extraction position C, and then poured into a preheated ladle.

When the furnace is tilted, the fulcrum of the tilting is placed near the tapping port so that the tapping port does not move much even when the furnace is tilted, making it easier to pour steel into the ladle. It is.

After discharging the molten steel, the emptied electric furnace 1 is moved to the next raw material supply position, where the interior of the furnace is cleaned, refractories are repaired, etc., and raw materials for the next process are supplied.

As the electric furnace goes around each position A, B, and C, it completes the process from supplying raw materials to melting, smelting, and tapping, and when two or three electric furnaces are installed at the same time, The same operation is repeated one after another to produce steel continuously.

Therefore, according to the present invention, (1) Preheating of the ladle can be performed at the place receiving the molten steel, so heat loss is extremely small, and there is no need to raise the tapping temperature, compared to the conventional tapping temperature of 1650°C. The one that was 1620-30
Even if the steel is tapped at ℃, no problems will occur in the subsequent steps, and therefore the wear and tear of the refractories in the furnace is extremely reduced, and the amount of electricity used is also reduced.

(2) Since the electrode does not need to be tilted together with the furnace, the structure of the furnace and its surroundings is simplified, which not only reduces equipment costs but also reduces the chance of failure.

(3) Since different operations such as melting (scouring), tilting (steel tapping), raw material input, preheating, etc. are not performed in the same place, but each work is performed in a dedicated place, efficiency is improved and productivity is improved.

(4) The electric furnace is tilted during tapping, but since it is done with a fulcrum near the tapping port, there is very little movement of the tapping port due to the tilting, so the ladle can be moved while receiving the S molten steel. There is no need for special skill, and there are no accidents in this regard.

It has many advantages such as

Additional related original invention patent No. 864562 (Japanese Patent Publication No. 51-33496
) is an electric furnace that runs on a loop-shaped rail to locate the raw material supply position, preheating position, melting position, scouring position, casting position,
In contrast to systems that move the electric furnace sequentially between standby positions, the present invention simplifies each work process, moves the electric furnace between each process by suspending it with a crane, etc., and pours the molten steel into the waiting ladle. This is done by tilting the electric furnace.

[Brief explanation of drawings]

Fig. 1 is a plan view showing the outline of the present invention, Fig. 2 is a cross-sectional explanatory view of the electric furnace at the raw material supply position, Fig. 3 at the melting and smelting position, and Fig. 4 at the molten steel extraction position. . 1... Electric furnace, 2... Lid, 3...
...Electrode, 4... Molten steel outlet, 5...
Electric furnace tilting device, 6...Ladle, A...
Raw material supply position, B... Melting and scouring position, C...
...Position for taking out molten steel.

Claims (1)

[Claims] 1. A raw material supply position where the refractories in the furnace are repaired and inspected and raw materials are supplied, and a melting and scouring position where the electric furnace is closed and melted and smelted.
The electric furnace with its lid opened is tilted to tap the molten steel.Three positions for taking out molten steel are arranged in a loop, each of which performs a different operation, and a plurality of electric furnaces are sequentially moved between the above-mentioned positions. A continuous steel manufacturing method characterized by continuous steel manufacturing.