JPS63131983A - Arc furnace for steel manufacture - 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 application field) This invention relates to an arc furnace for steel making.

(Prior Art) Conventionally, as shown in FIG. 4, an electric arc furnace for steelmaking is constructed by covering a tiltable container-shaped furnace body 31 with a furnace lid 33 through which an electrode 32 passes. A type having a gutter 34 for tapping hot water and a slag outlet 35 on the other side is widely used. 36 is a door that opens and closes the slag outlet 35''. In this arc furnace 37, it is necessary to tilt the furnace body 31 largely toward the gutter 34 side when tapping the metal.
An arc furnace 40 shown in the figure has been proposed. This arc furnace 40 has a tap hole 43 provided at the bottom of a protruding container portion 42 protruding from the side of a furnace body 41, and this tap hole 43 is opened and closed by a bottom cover 44. It is adapted to tilt toward the protruding container portion 42 and toward the opposite side.

(Problems to be Solved by the Invention) However, among the above-mentioned conventional arc furnaces, the arc furnace 37 shown in FIG. The tilting angle of the main body 31 is large, and since the furnace main body 31 is tilted in the opposite direction as shown by the chain line 38 during tapping, the tilting range of the furnace main body 31 is large, and the ladle 24 is moved below the gutter 34 during tapping. During slag tapping, it is necessary to position the slag receiving steel 23 below the slag tapping port 35, which requires a large space below both sides of the furnace body 31. Further, in the arc furnace 40 shown in FIG. 5, the tilting angle of the furnace body 41 during tapping is smaller than that of the arc furnace 37, and the slag can be tapped through the tapping port 43 at the end of the operation. In order to remove slag midway, it is necessary to tilt the furnace body 41 in the opposite direction to the protruding container portion 42 as shown by the chain line 45 and to remove the slag from the operation port 46. The tilting range is large, and like the arc furnace 37, the ladle 24 and the slag receiving ladle 23 are located on both sides below the furnace body 41, so a large space is required.

This invention solves the above-mentioned conventional problems; the tilting range of the furnace body is small, the tilting drive device can be small, and the space required for tapping and tapping the slag around the furnace body is small. The purpose is to provide an arc furnace for steelmaking.

(Means for Solving the Problems) In order to achieve the above object, the steelmaking arc furnace of the present invention is comprised of a tiltable furnace body covered with a furnace lid through which an electrode penetrates. A slag outlet and a door for opening and closing the slag outlet are provided on the side of the furnace body, and a molten metal outlet and a bottom cover for opening and closing the slag outlet are provided at the bottom of the furnace near the slag outlet.

(Function) In the steel-making arc furnace of the present invention, tapping is performed by opening the bottom cover at the bottom of the furnace and allowing molten steel to flow out from the tapping port. Therefore, the tilting angle of the furnace body may be small. Slag removal during operation is performed by opening the door on the side of the furnace body on the same side as the tapping port and letting the slag flow out from the tapping port. Therefore, since the furnace body only needs to be tilted in the same direction as when tapping, the range of tilting of the furnace body is small. Further, since both tapping and slag tapping are performed on the slag tapping side of the furnace body, no space for tapping the steel is required on the side of the furnace body opposite to the slag tapping opening.

(Example) An example of the present invention will be described below with reference to FIGS. 1 and 2.

In the figure, 1 is a container-shaped furnace body, 2 is a furnace lid that is removably placed on the furnace body 1, and 3 is three electrodes that are inserted and removed into the furnace body 1 through the furnace lid 2. It is. A protruding container portion 4 is provided on the side of the furnace body 1 so that substantially the lower half of the furnace body protrudes laterally. The furnace body 1 has a furnace shell 5 made of steel plate.
A water-cooled box 8 is buried on the inner periphery of the furnace wall 6 at a distance of 1 it (typically 400 m) from the slag surface 7, and a water-cooled box 8 is buried in the furnace bottom 9 of the furnace body 1 and The hearth portion of the hearth bottom 10 of the continuous protruding container portion 4 is coated with a stamp layer of magnesia clinker or the like.11
1 is a tap hole drilled in the hearth bottom 10 of the protruding container portion 4, which is lined with a refractory material 12 and has a bottom cover 13 covered with the refractory material pivoted to the hearth bottom 10, and is driven to open and close by an operating cylinder (not shown). It is supposed to be done. Reference numeral 14 denotes a slag outlet that also serves as an operation port and penetrates the protruding end wall 15 of the protruding container portion 4;
A door 16 opens and closes the slag outlet 14, and is driven up and down by an air cylinder 17.

In addition, 18 is a furnace stand fixedly installed on the foundation 19, and 20 is a furnace main body 1.
This furnace leg 20 is fixed to the furnace base 18 and moves over the furnace stand 18.
A rocker-type tilting device is formed which engages with the furnace stand 18 and tilts and drives the furnace body 1 by a hydraulic or electric cylinder 21.

In the arc furnace 22 having the above configuration, when removing slag during steelmaking operations, the door 16 is opened and a known slag scraper is used to remove the slag.
If necessary, the furnace body 1 is tilted in the direction in which the protruding container portion 4 descends as shown by the arrow X, and the slag is discharged into the slag receiving w423 located below the slag outlet 14. When tapping, the bottom cover 13 is opened, the furnace body 1 is tilted in the direction of the arrow X as required, and the steel is tapped into a ladle 24 located below the tap 11.

In this way, since the furnace body 1 only needs to be tilted from the horizontal position in the direction of the arrow X, the tilting range of the furnace body 1 is small, and the cylinder 21 may be small.

In addition, the opposing furnace wall portion 6 on the side opposite to the protruding container portion 4 side (steel tapping side)
A does not have an opening like a conventional slag outlet, and the water cooling box 8 can also be installed in this part.Furthermore, since the furnace body 1 does not need to be tilted in the direction opposite to the arrow The water-cooled box 8 near the furnace wall 6a can be provided close to the slag surface 7, and the amount of refractory used for the furnace wall 6 can be reduced, making it easier to repair the refractory. Furthermore, the ladle 24 and the slag receiving pan 2
3 are both located below the protruding container part 4, so there is no need to take space for tapping or tapping the slag on the opposite side of the protruding container part 4, and the working space around the furnace body 1 is small. The layout of corner arc furnace installation becomes easier.

The present invention is not limited to the above-mentioned embodiments, but includes, for example, the shape of the protruding container portion 4, the tap hole 11, and the slag tap port 14.
The shape, the opening/closing drive mechanism of the bottom cover 13 and the door 16, etc. may be other than those described above.

Further, in the above embodiment, the tap hole 11 is provided in the furnace bottom 10 of the protruding container part 4, but if the furnace body 1 does not have the protruding container part 4 as shown in FIG. A slag port 14 may be provided, and a tapping port 11 may be provided at the bottom 9 of the furnace body 1.

In the figure, the same or equivalent parts as in FIG. 1 are given the same reference numerals as in FIG. 1.

(Effects of the Invention) As explained above, according to the present invention, since the tapping port and the slag tapping port are provided in the protruding container part, both tapping and slag can be done by tilting the furnace body toward the protruding container part. The tilting range of the furnace body is small, and the tilting drive device can be small. Further, both tapping and tapping of slag are performed on the side of the protruding container, and no space is required for tapping or tapping the slag on the side opposite to the projecting container, so the space required around the furnace body can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of an arc furnace showing one embodiment of the present invention, Fig. 2 is a sectional view taken along line A-A in Fig. 1, and Fig. 3 is a longitudinal sectional view of an arc furnace showing another embodiment of the invention. 4 and 5 are longitudinal sectional views showing examples of conventional arc furnaces. 1... Furnace body, 2... Furnace lid, 3... Electrode, 4...
・Protruding container part, 6... Furnace wall, 9... Hearth bottom, 10...
・Bottom of hearth, 11... Outlet, 13... Bottom cover, 14.
..., slag opening, 15... protruding end wall, 16... door, 1
7... Air cylinder, 18... Furnace stand, 20... Short leg, 21... Cylinder, 22... Arc furnace.

Claims (1)

[Claims] In an arc furnace for steelmaking, which has a tiltable furnace body covered with a furnace lid through which an electrode passes, a slag outlet and a door for opening and closing the slag outlet are provided on the side of the furnace body, and the slag outlet An electric arc furnace for steel making, characterized in that a tap hole and a bottom cover for opening and closing the tap hole are provided at the bottom of the furnace near the furnace bottom.