JPS628487B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for replacing tuyeres at the bottom of a bottom-blown converter or a combined top-blown and bottom-blown converter.

In a bottom-blown converter, the furnace life is dominated by the life of the tuyere bricks. In other words, the life of the tuyere bricks is controlled by the refractory material, the degree of cooling by bottom-blown gas, and the degree of repair effects such as slag coating, but there are limits to this at the current technological level. A method of exchanging is adopted.

However, the conventional method involves the dismantling of the tuyere bricks, etc., so it takes a long time to dismantle and insert the tuyere bricks, and the construction accuracy is also poor.
That is, after removing the tuyere flange iron skin during dismantling, the base must be broken using a brick demolition machine or a breaker. After that, it is necessary to pull out the tuyere bricks or melt down metal fittings such as gas blowing pipes and then break them using a demolition machine and a breaker.The tuyere bricks at this time are sticky and difficult to break due to their high heat. As a result, the bricks around the tuyeres were damaged and dismantling took a long time. Furthermore, when inserting the tuyeres, it took a long time to insert the tuyeres and the base separately and by using a fork or by hand, and the accuracy of construction was also poor. Therefore, this was not necessarily a sufficient method for replacing the tuyere.

The present invention is a method for replacing tuyeres in a short time and with high precision.

That is, the gist of the present invention is to attach an attachment to the rear end of the gas blowing pipe to the tuyere in a converter bottom blowing tuyere having the specific structure shown below, connect a pull-out tool to this attachment, and pull out the pipe. The method involves pulling out the tuyere bricks, wind box, and base at the same time. In addition, the above-mentioned three types can be inserted simultaneously.

According to the present invention, (1) the tuyere brick, the wind box, and the base can be pulled out at the same time, making it possible to replace the tuyere in a short time. (2) Due to the attachment method,
The gas blowing pipe to the tuyere can be reused, and it is easy to connect to the extraction device, and by preparing attachments with different shapes, it can be used depending on the application. (3) The use of brick dismantling machines and breakers is kept to a minimum, and the bricks around the tuyeres are not damaged. (4) Furthermore, since the tuyere bricks, wind box and base can be set in advance before insertion, construction accuracy is also improved. It has excellent effects such as:

Examples of the present invention will be described in detail below.

FIG. 1 is a detailed cross-sectional view of the bottom blowing tuyere that is the object of the present invention. In FIG. 1, 1 is a converter bottom, 2 is an iron shell, 3 is a bottom wear refractory, and 4 is a bottom permanent refractory. Reference numeral 5 indicates a tuyere brick, 6 a retaining brick, and 7 a bottom blowing tuyere inserted into a hole of the tuyere brick 5. This bottom blowing tuyere 7 has a plurality of metal pipes 9 buried therein which penetrate the nozzle refractory 8, and the lower end of each metal pipe 9 is connected to a metal wind box 1.
0 by welding or the like, and a gas supply pipe 11 is connected to the lower surface of this wind box 10.

That is, the desired gas supplied from the gas supply pipe 11 enters the wind box 10, is distributed to each metal pipe 9, and is blown into the molten steel in the furnace from the tip of each metal pipe 9. It's summery. Next, 12 and 13 are the upper and lower base lines, which are 1
It may be one piece. Reference numeral 14 denotes a flange, which is fixed to the iron skin 2 by a bolter 15.

The embodiment of the bottom blowing tuyere to which the present invention is directed is as described above, and next, an embodiment of tuyere replacement will be described with reference to FIGS. 2 and 3.

In FIGS. 2 and 3, reference numeral 16 denotes an attachment that connects the gas supply pipe 11 and the pull-out rod 17. A pull-out rod coupling member 21 that is screwed onto a threaded portion 20 provided in 17.
and a pin 22 for connecting both the connecting members 19 and 21.

The rear end of the above-mentioned pull-out rod 17 is connected to a powerful small stroke hydraulic cylinder 23 as shown in FIG. It is listed on the tower. Note that 26 in the figure indicates a stopper.

The embodiment of the extraction device according to the present invention is as described above, and by operating the small stroke hydraulic cylinder 23 in the state shown in FIG. The reason why the bottom blowing tuyere 7 consisting of the pipe 9, the wind box 10, and the base bricks 12 and 13 can be removed from the hearth bottom at the same time is as follows.

First, as a preparation, the flange 14 is removed. Next, when the gas supply pipe 11 is pulled, the pulling force is
0 and the base bricks 12 and 13 present at the bottom of the wind box 10 are the tuyere bricks 5 and the holding bricks 6
Peel from. On the other hand, a plurality of through pipes 9 are buried under pressure inside the nozzle refractory 8, and the frictional resistance between the through pipe group and the nozzle refractory 8 is sufficiently large. Also peels off from the tuyere brick 5.

By pulling the gas supply pipe 11 in this way, three parts (the bottom tuyere 7, the wind box 10, the base brick 1)
2 and 13) can be removed from the hearth at the same time.

In addition, when setting a new bottom blowing tuyere 7, the inner surfaces of the tuyere bricks 5 and the retaining bricks 6 are cleaned,
After applying mortar, perform the reverse operation of pulling out.

In the embodiments described above, the attachments 16 are connected using a screw type, but the present invention is not limited to this, and it goes without saying that any type of connection, such as a chuck type, can be used.

According to the above replacement method of the present invention, the above-mentioned (1) to (4)
As shown in Figure 2, it has a great effect on workability, applicability, and construction accuracy, and has a great impact on bottom-blowing converter operation.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a cross-sectional view of the bottom blowing tuyere, FIG. 2 is an explanatory view of the extraction device,
FIG. 3 is a detailed sectional view of the attachment. 7; Bottom blowing tuyere, 8; Nozzle refractory, 9; Penetration pipe, 10; Wind box, 11; Gas supply pipe, 16; Attachment, 25; Pull-out trolley.

Claims (1)

[Claims] 1. A wind box for supplying gas to the through pipes is provided at the bottom of the tuyere refractory where a large number of through pipes are installed, a gas supply pipe is connected to this wind box, and a gas supply pipe is connected to the bottom of this wind box. When replacing the bottom blowing tuyere with a base brick installed, attach an attachment to the rear end of the gas supply pipe, connect a pull-out device to this attachment, and pull out the gas supply pipe to remove the bottom blowing tuyere. A method for replacing a converter bottom blowing tuyere characterized by simultaneously removing the mouth, wind box and base brick from the hearth bottom.