JPH0238511A - Tuyere for bottom blowing converter and charging method thereof - Google Patents

Abstract

PURPOSE:To shorten changing time of tuyere by filling up monolithic refractory into a metallic frame having reverse tapered-shape downward at outer circumference forming preliminary tuyere and fitting/removing to opening part of the tuyere through supporting metal arranging at lower part of the metallic frame. CONSTITUTION:The monolithic refractory 3 is filled up into the metallic frame 2 forming with the outer circumferential part 2a having reverse tapered-shape downward and closed bottom part 2b from the upper opening part to constitute the preliminary tuyere 1 and the supporting metal 2c is arranged at lower end part of the metallic frame 2. At the time of fitting the preliminary tuyere 1, the outer circumferential part 2a of the metallic frame 2 is inserted in the opening part 6a of the tuyere, and after fitting a fitting holes 2d arranging to the supporting metal 2c into a fixed metal 2 on iron shell 4 at furnace bottom, cotters 8 are driven in to support the opening part 6a of the tuyere and the outer circumferential part 2a of the metal 2 are supported under closely contacting condition. At the time of removing the preliminary tuyere 1, this can be easily removed out of the furnace integratedly with a pulling-out device through the supporting metal 2c.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a bottom-blowing converter blade, which has a plurality of tuyeres provided at the bottom of the bottom-blowing converter furnace and is capable of replacing the blades. It concerns the mouth and how to replace it.

<Prior art> In an oxygen bottom-blown converter or a top-bottom blown converter, a refining gas blowing blade I is provided at the bottom of the furnace, and oxygen, propane gas, or an inert gas is injected through the tuyere. The steelmaking efficiency is improved by stirring the molten steel.

By the way, when refining gas is injected through the tuyere, the tuyere and its surrounding refractories are locally subjected to large II scratches due to the strong stirring of molten steel and slag accompanying the steelmaking reaction. Conventionally, in order to maintain the balance of melting loss of the entire converter refractory, measures have been taken such as making the bottom part of the furnace, which suffers a lot of wear, replaceable.

However, the wear rate of the tuyeres and surrounding refractories is generally more than twice as high as that of other parts of the hearth bottom, and therefore the hearth bottom must be replaced every time the tuyeres are locally worn. Not only was this economically disadvantageous, but it also led to a significant drop in operating rates.

In this respect, if only the tuyeres could be repaired, the above problems would be alleviated considerably, and in order to repair only the tuyeres, various methods have been proposed to repair or replace the tuyeres that have been melted down. ing.

For example, as a means of repairing only the tuyeres, there is
158240 and Japanese Patent Application Laid-Open No. 58-39719, a new tuyere is installed in the opening after the melted tuyere has been removed, and a monolithic refractory is filled between the opening and the new tuyere. A method for repairing the problem is disclosed.

Furthermore, in Japanese Patent Application Laid-Open No. 59-41414, the opening after removing the damaged tuyere is filled with monolithic refractory material, a hole is drilled in the monolithic refractory material using a drill, etc., and a new tuyere is installed. ” has been disclosed, and a similar one is disclosed in Japanese Unexamined Patent Publication No. 5
7-54527, a working tuyere and a spare tuyere are provided, and the spare tuyere is filled with monolithic refractory, and when the working tuyere is melted, the monolithic refractory of the spare tuyere is replaced. A method is disclosed in which a new tuyere is installed by drilling a hole with a drill or the like.

As a means for replacing the tuyeres, for example, Japanese Patent Application Laid-Open No. 5913640
Publication No. 8 discloses that an attachment is attached to the rear end of the gas blowing pipe to the tuyere, a pulling tool is connected to this attachment, and by pulling out this pipe, the tuyere brick, wind box, and base can be pulled out at the same time. In addition, in Japanese Patent Application Laid-Open No. 59-129710, a locking part for connecting the tuyere holding hardware and a sleeve brick is formed, and the tuyere is inserted by a melted shell. A repair is disclosed in which only the sleeve brick is replaced.

<Problems to be Solved by the Invention> Among the conventional techniques described above, those in which monolithic refractories are filled between the tuyere opening and the new tuyere for repair, the filling of monolithic refractories is insufficient. Not only is this part prone to melting and damage, but it also takes a long time to work.

In addition, when installing new tuyeres by drilling holes in monolithic refractories, it is difficult to form the drilled surface accurately, and the tuyere inserted after drilling does not fit properly. There is a problem in that it takes a long time to output the data.

If the tuyere brick, wind box, and base are pulled out at the same time through an attachment attached to the rear end of the gas blowing pipe, the tuyere brick may break and a portion of the tuyere brick may fall into the tuyere opening. It tends to remain and it takes a long time to remove the remaining bricks. Similarly, when the tuyere holding hardware and the sleeve brick are connected at their respective connecting locking portions, the locking portions of the sleeve brick tend to break when the damaged tuyere is removed, and some of the sleeve bricks are attached to the tuyere opening. There is a problem that bricks remain and it takes time to remove them.

The present invention solves the above-mentioned problems of the prior art, and provides a tuyere for a bottom-blowing converter with good workability and a method for replacing the same, which can shorten the time required to switch from a damaged tuyere to a new one. The purpose is to

<Means for Solving the Problems> In order to achieve the above object, the tuyere of the bottom blowing converter of the present invention has a plurality of tuyere openings arranged at the bottom of the converter, an operating tuyere and a spare tuyere. In the tuyere of a bottom-blown converter equipped with a tuyere, the preliminary tuyere has a metal frame whose outer periphery is tapered to widen downward, and is open at the top and closed at the bottom, and a monolithic refractory filled in the metal frame. and a support metal fitting provided at the lower end of the metal frame, and the spare tuyere is detachably attached to the tuyere opening in the bottom of the converter via the support metal fitting. It is something to do.

The tuyere replacement method for a bottom-blowing converter of the present invention also includes: a metal frame having a tapered outer periphery that widens downward, an open upper part and a closed lower part; a monolithic refractory filled in the metal frame; This method is characterized in that a spare tuyere consisting of a supporting metal fitting provided at the lower part of the metal frame is removed, and a new working tuyere is attached to the tuyere opening from which the spare tuyere has been removed.

<Function> The spare tuyere attached to the tuyere opening at the bottom of the converter hearth has a tapered bottom on the outer periphery of the metal frame, so the spare tuyere can be easily removed from the tuyere opening. is possible.

In addition, after the spare tuyere is removed, the brick surface of the tuyere opening can maintain its normal shape due to the metal frame, making it possible to easily and securely install a new working tuyere. Not only can the working time required for installing the spout be shortened, but also the life of the operating tuyere can be extended.

<Example> Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a preliminary tuyere according to the present invention.

In FIG. 1, reference numeral 1 denotes a preliminary tuyere, and the preliminary tuyere 1 has a metal frame 2 formed by a tapered outer peripheral part 2a and a closed bottom part 2b.
A supporting hardware 2c is provided at the lower end of the metal frame 2.

4 is a hearth bottom shell 15 is a hearth bottom refractory, 6 is a tuyere brick, 6a
7 is a tapered tuyere opening at the bottom of the tuyere brick 6, and 7 is a fixed metal fitting provided on the hearth bottom shell 4.

When installing the spare blade I 2, insert the outer circumferential part 2a of the metal frame 2 into the tuyere opening 6a, and use the mounting hole 2d provided in the support hardware 2c at the lower end to fix the bottom iron shell 4. After fitting into the metal fitting 7, a contour 8 is driven in to connect the tuyere opening 6a and the metal frame 2.
The outer periphery 2a of the holder is supported in close contact with the outer periphery 2a of the holder.

When removing the spare tuyere 1, after pulling out the cotter 8, the spare tuyere 1 can be easily taken out of the furnace as a whole by means of a pulling device (not shown) via the supporting hardware 2C.

FIGS. 2(a) and 2(b) are plan views schematically showing the working tuyeres and spare tuyeres arranged at the bottom of the converter. Two spare tuyeres 1b are shown in each case.

First, in Fig. 2(a), when the operating tuyere 1a is damaged due to blowing in the bottom blowing converter, after removing the operating tuyere 1a, the tuyere opening shown in the second ID (b) is Attach the spare tuyere 1b as shown. If the tuyere opening has an IN scratch or the like and is not suitable for installing the spare tuyere 1b, the tuyere opening is filled with monolithic refractory and closed.

On the other hand, in order to attach the operating tuyere 1a to the spare tuyere 1b in Fig. 2(a), first remove the spare tuyere 1b, and attach the operating tuyere to the tuyere opening as shown in Fig. 2(b). Once the tuyere 1a is installed, the series of replacement work is completed.

In the above example, two working tuyeres and two spare tuyeres are installed at the hearth bottom.
Although we have explained that each tuyere is arranged separately, it is not limited to two each; it is preferable to have the same number of spare tuyeres or a multiple of the number of working tuyeres, and the working tuyere and spare tuyere should be arranged close to each other alternately. It is desirable that

Note that the present invention is applicable to any structure of tuyere, such as a double-tube tuyere, a tuyere consisting of a large number of thin tubes, and a porous plug tuyere.

<Effects of the Invention> As explained above, according to the present invention, it is easy to attach and detach the spare tuyere and subsequently attach the working tuyere, so that replacement work can be carried out in a short time. Furthermore, since the working tuyeres can be fitted accurately into the tuyere openings, it is possible to extend their service life.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing the first tuyere of the present invention;
The figure is a plan view showing the arrangement of the preliminary tuyere and the working blade I of the present invention. 1...Spare feather I, 2...Metal frame, 2
a... Outer periphery having a tapered lower floor, 2b...
Bottom 01;, 2C... support (h hardware, 3...
Irregular i4 refractory, 4... Hearth bottom shell, 5... Hearth bottom refractory, 6... Feather c1 brick, 6a...
Wing n opening, 7... fixed hardware, 8... cock. Special agreement applicant Kawasaki Steel Corporation <a> (b)

Claims (1)

[Scope of Claims] 1. In the tuyeres of a bottom-blowing converter in which a plurality of tuyere openings arranged at the bottom of the converter are equipped with working tuyeres and spare tuyeres, the outer periphery of the spare tuyeres is lower. It is composed of a metal frame that has a widening taper and is open at the top and closed at the bottom, a monolithic refractory filled in the metal frame, and a supporting hardware provided at the lower end of the metal frame. A tuyere for a bottom-blowing converter, characterized in that the spare tuyere is removably attached to the tuyere opening in the bottom of the converter via. 2. It is composed of a metal frame whose outer periphery is tapered downward and whose upper part is open and whose lower part is closed, a monolithic refractory filled in the metal frame, and supporting hardware provided at the bottom of the metal frame. 2. The tuyere replacement method for a bottom-blowing converter according to claim 1, characterized in that the spare tuyere is removed, and a new working tuyere is installed in the tuyere opening from which the spare tuyere was removed.