WO2019012601A1

WO2019012601A1 - Furnace body and bottom-blowing plug

Info

Publication number: WO2019012601A1
Application number: PCT/JP2017/025253
Authority: WO
Inventors: 邦博小出; 智裕津田
Original assignee: 東京窯業株式会社
Priority date: 2017-07-11
Filing date: 2017-07-11
Publication date: 2019-01-17
Also published as: JP6780115B2; JPWO2019012601A1

Abstract

Provided are: a furnace body in which assembly of refractory bricks and bottom-blowing plugs is excellent; and a bottom-blowing plug. This furnace body 1 comprises: an iron furnace body shell 2 with a round bottom surface that forms the outer shell of a furnace body 1 of a converter furnace, etc.; floor bricks 3 disposed on the bottom surface in the radial direction and the circumferential direction and made of refractory material molded in specified shapes; and bottom-blowing plugs 4 with a main body part 40 that is made of refractory material formed to be larger than the floor bricks 3 and a through hole 41 provided so as to pass through the main body part 40. The main body parts 40 have trapezoidal peripheral shapes in which the radially inward side forms an upper bottom surface 40a and the outward side forms a lower bottom surface 40b, the upper bottom surface 40a being concave to the outward side and the lower bottom surface 40b being convex to the outward side. The bottom-blowing plug 4 of the present invention has said main body section 40.

Description

Furnace body and bottom blow plug

The present invention relates to a furnace body and a bottom-blowing plug provided with a bottom-blowing plug for storing molten metal such as molten steel inside and blowing gas to the stored molten metal.

Conventionally, a converter is used to process molten steel. The converter stores molten steel inside the furnace body. At the bottom (furnace bottom) of the converter, a bottom-blowing plug for gas injection provided with a plurality of through holes through which gas passes is disposed. The bottom blowing plug supplies gas (inert gas such as argon) to the molten steel from the furnace bottom through the through holes, and stirs the molten steel. By this stirring, the temperature / components of the molten steel in the furnace are homogenized and cleaned. Similar treatment takes place not only in the converter but also in the furnace body provided with the bottom-blowing plug.
A furnace body for storing molten steel having such a bottom-blowing plug is described, for example, in Patent Document 1 (Japanese Patent Application Laid-Open No. 11-217613).
In Patent Document 1 (Japanese Patent Laid-Open No. 11-217613), a furnace shell, a refractory brick lined and disposed inside the furnace shell, and a bottom-blowing nozzle (bottom-blowing plug provided on the furnace bottom) A furnace body is described which is also referred to as

In general, refractory bricks (also referred to as laying bricks) have a predetermined shape, and are arranged in the radial and circumferential directions on the surface of the furnace shell at the furnace bottom. As the predetermined shape of the refractory material brick, the outer peripheral shape when looking at the furnace bottom from inside the furnace can be a rectangular shape or a substantially trapezoidal shape whose outer diameter side is wide.

The bottom blowing nozzle has a configuration in which a through hole is opened in a main body made of a refractory brick larger than the refractory brick, and the gas is blown into the molten steel by supplying the gas through the through hole. The main body portion has a shape larger than that of the other refractory bricks (a shape having a large outer peripheral shape when the furnace bottom is viewed from the inside of the furnace). For example, the main body has a length in the radial direction and circumferential direction of three other refractory bricks.

JP-A-11-217613

However, the main body portion used in the conventional furnace body has a trapezoidal outer peripheral shape whose outer peripheral shape is a lower base whose outer diameter side is wide. The main body portion is formed such that an upper base located on the inner diameter side and a lower base located on the outer diameter side extend in a direction perpendicular to the radial direction and in parallel with each other. In this configuration, each of the surface on the inner diameter side and the surface on the outer diameter side of the main body portion creates a large gap between the ordinary refractory bricks. In order to eliminate this gap, the adjustment brick corresponding to the shape of the main body was used.

As described above, in the conventional furnace body, when arranging the bottom blowing nozzle using the main body, an adjustment brick is required separately from the refractory material brick. The adjustment bricks had to have a shape corresponding to the main body, and the outer peripheral shape of the adjustment brick was different, and the assemblability was reduced. As a result, in the conventional furnace body using adjustment brick, there existed a problem that the assemblability of a refractory material brick and a bottom blow plug fell.
The present invention has been made in view of the above-mentioned circumstances, and is a furnace body excellent in the assemblability of the laying brick (refractory brick) and the bottom blowing plug (bottom blowing nozzle) and a bottom blowing excellent in the assembling property to the furnace. The task is to provide a plug.

The furnace body of the present invention for solving the above problems is a furnace body having a circular bottom surface which forms the outer shell of a furnace body such as a converter, and a predetermined number arranged in the bottom surface along the radial and circumferential directions. A bottom-blowing plug including a laying brick made of a fire-resistant material molded into a shape, a main body made of a fire-resistant material formed to be larger than the laying brick, and a through hole provided through the body; A furnace body having a trapezoidal outer shape in which the inner diameter side in the radial direction is an upper base and the outer diameter side is a lower base, and the upper base is concaved to the outer diameter side; Is convex on the outer diameter side.

According to this configuration, the upper and lower bases of the trapezoidal main body portion are deformed to the outer diameter side, and the gap between the radially inward and the radially outward located laying bricks is reduced. It is possible to eliminate the need to use conventional adjustment bricks. That is, the furnace body can be formed without using the conventional adjustment brick, and the problem of the decrease in the assemblability caused by using the adjustment brick does not occur. As a result, the furnace body of the present invention is a furnace body excellent in the assemblability of the refractory brick and the bottom blow plug.

According to the present invention, it is preferable that the upper and lower bases of the main body have either a smooth arc shape or a shape having corners.
When the upper and lower bases of the main body portion have these shapes, it is possible to reliably reduce the gap (the distance between the facing surfaces) with the laying bricks positioned radially inward and radially outward. The assembly can be performed without arranging a specially shaped brick like the conventional adjustment brick.

According to the present invention, it is preferable that the main body portion has a smooth arc shape on the upper base and a lower base having a corner. With each of the upper and lower bases having this shape, the gap with the laying brick can be reliably reduced.

The bottom-blown plug according to the present invention for solving the above-mentioned problems has a bed made of a refractory material molded in a predetermined shape, arranged along the radial and circumferential directions on the bottom of a furnace having a circular bottom such as a converter. A bottom-blowing plug to be installed between bricks, the bottom-blowing plug comprising: a main body portion made of a refractory material formed to be larger than the laying brick; and a through hole provided through the main body portion The body portion has a trapezoidal outer shape in which the inner diameter side in the radial direction is the upper base and the outer diameter side is the lower base, the upper base is concaved to the outer diameter side, and the lower base is convex to the outer diameter side It is characterized by being.

According to this configuration, the upper and lower bases of the trapezoidal main body portion are deformed to the outer diameter side, and the gap with the laying bricks disposed radially inward and radially outward is small. It is possible to do without using the conventional adjustment bricks. That is, it can assemble | attach to a furnace body, without using the conventional adjustment brick, and the problem of the fall of the assemblability which arises by having used the adjustment brick does not arise. As a result, the bottom-blown plug of the present invention is excellent in the assemblability to the furnace body.

According to the present invention, it is preferable that the upper bottom and the lower bottom of the main body have a shape that substantially matches the inscribed circle or the circumscribed circle of the facing surface of the laying brick facing in the radial direction. According to this configuration, when the bottom-blowing brick is assembled, the gap between the laying bricks located on the inner diameter side and the outer diameter side can be reliably reduced.

According to the present invention, it is preferable that the upper and lower bases of the main body have either a smooth arc shape or a shape having corners. When the upper and lower bases of the main body portion have these shapes, it is possible to reliably reduce the gap (the distance between the facing surfaces) with the laying bricks positioned radially inward and radially outward. The assembly to the furnace body can be performed without arranging the specially shaped brick like the conventional adjustment brick.

According to the present invention, it is preferable that the main body portion has a smooth arc shape on the upper base and a lower base having a corner. When each of the upper and lower bases has this shape, the gap between the upper and lower bases can be reliably reduced when assembled to the furnace body.

It is a sectional view showing composition of a furnace of an embodiment. It is a top view which shows the bottom of the furnace body of embodiment. It is a top view which shows the structure of the bottom blowing plug vicinity in the furnace body of embodiment. It is a top view which shows the structure of the bottom blowing plug of embodiment. It is a top view which shows the structure of the bottom blowing plug in another form of embodiment.

Hereinafter, the present invention will be specifically described using embodiments.
[Embodiment]
The present embodiment is a furnace body provided with a bottom blow plug 4 at the furnace bottom. The furnace body 1 of the present embodiment is used for a converter.
The furnace body 1 of the present embodiment has a furnace body shell 2, a laying brick 3, and a bottom blowing plug 4, as shown in a sectional view in FIG.
The furnace shell 2 forms the outer shell of the furnace 1 as shown in FIG. The furnace shell 2 has a circular bottom 2a. The furnace shell 2 can have the same configuration as that of a shell used in a conventional furnace.

The laying brick 3 divides the space in the furnace of the converter for storing molten metal such as molten steel.
The laying bricks 3 are molded into a predetermined shape. The predetermined shape of the laying brick 3 is a columnar shape having a constant outer peripheral shape in the axial direction. The laying brick 3 has an end face shape (also referred to as an outer peripheral shape) having a trapezoidal shape in which the inner diameter side is an upper base and the outer diameter is a lower base, as shown in FIGS. The trapezoidal shape of the laying brick 3 is such that the upper and lower bases are parallel. In addition, in FIG. 2, the state in which the laying bricks 3 were arranged in the circumferential direction is shown by the concentric circle. In FIG. 3, the circumferential direction in which the laying bricks 3 are arranged in the circumferential direction is indicated by a broken line. The cross-sectional view of FIG. 1 corresponds to a cross-sectional view taken along the line II in FIG.
The laying bricks 3 are arranged on the bottom surface 2 a of the furnace shell 2 along the radial direction and the circumferential direction. As shown in FIGS. 2 to 3, the upper base is arranged on the inner diameter side and the lower base is arranged on the outer diameter side. 2 to 3 schematically show that the laying bricks 3 are arranged along the circumferential direction, and the boundary of the laying bricks 3 is omitted.
The material of the laying brick 3 is not limited. The same material as the laying bricks used for the conventional converter can be used. For example, a highly durable magnesia-carbon material can be used.

The bottom blowing plug 4 is provided with a main body 40 made of a refractory material formed to be larger than the laying brick 3 and a through hole 41 provided through the main body 40. The main body portion 40 has an outer peripheral shape having a trapezoidal shape in which the inner diameter side in the radial direction is the upper base and the outer diameter side is the lower base. The outer peripheral shape is an outer peripheral shape when the end face of the bottom blowing plug 4 is viewed in the axial direction of the through hole 41, and is an outer peripheral shape when the bottom blowing plug 4 is viewed from above the furnace body 1. The upper bottom surface 40a corresponding to the upper bottom of the trapezoidal shape is concave toward the outer diameter side, and the lower bottom surface 40b corresponding to the lower bottom of the trapezoidal shape is convex toward the outer diameter side. The upper bottom surface 40a and the lower bottom surface 40b are connected by a pair of

side surface

40c, 40c corresponding to the side connecting the upper and lower bases of the trapezoidal shape. The pair of

side surfaces

40c, 40c are flat so that the corresponding trapezoidal shape is linear. The trapezoidal shape which is the outer peripheral shape of the main body portion 40 includes a substantially trapezoidal shape in which the upper bottom surface 40 a and the lower bottom surface 40 b are not parallel. The bottom blowing plug 4 blows the gas from the outside into the molten metal stored in the furnace body 1 through the through hole 41.

The main body portion 40 of the bottom blowing plug 4 is made of a refractory material formed to be larger than the laying brick 3. The larger size of the laying brick 3 in the main body 40 indicates that the trapezoidal shape of the outer peripheral shape of the main body 40 is larger in area than the trapezoidal shape of the laying brick 3.

The material of the main body 40 is also not limited. The same material as the main body of the conventional bottom-blowing plug can be used. Moreover, the same material as the material used for the laying brick 3 can be used. The material of the main body 40 and the material used for the laying brick 3 may be the same material or different materials.

The main body portion 40 opposes the outer peripheral surface 3 b of the two (one or more, multiple) laying bricks 3 with the upper bottom surface 40 a. The upper bottom surface 40a of the main body portion 40 is shaped so as to be concave radially outward, and in detail, the upper end of the corresponding trapezoidal shape is formed so as to form a smooth arc shape. The arc-like shape of the upper bottom surface 40a is an arc shape which substantially matches the circumscribed circle of the outer peripheral surface 3b of the two laying bricks 3 opposed to the upper bottom surface 40a.

The main body portion 40 opposes the inner peripheral surface 3 a of the laying brick 3 having four lower bottom surfaces 40 b (a plurality of numbers larger than the upper bottom surfaces 40 a). The lower bottom surface 40b of the main body 40 has a curved shape that is convex outward in the radial direction, and more specifically, has a shape having corner portions (specifically, a shape having three corner portions) . The curved shape of the lower bottom surface 40 b is a shape that substantially matches the inner peripheral surface 3 a of the four laying bricks 3 facing the lower bottom surface 40 b. In addition, the circumscribed circle of the lower bottom surface 40b coincides with the inscribed circle of the inner peripheral surface 3a of the four laying bricks 3 opposed to the lower bottom surface 40b.

A pair of

linear side surface

40c, 40c has a linear shape that coincides with the

similar side surfaces

3c, 3c of the trapezoidal shaped laying brick 3. In the present embodiment, the length of the pair of

linear side surface

40c, 40c matches the length of the three laying bricks 3 aligned in the radial direction.

The through hole 41 can also be received through the main body 40. The through holes 41 allow gas to flow from the outside to the inside of the furnace body 1 in the bottom blowing plug 4. The through hole 41 forms an outlet for blowing out gas on the surface of the main body 40. The through holes 41 are formed in the same manner as the through holes through which the gas flows in the conventional bottom blow plug 4. That is, the through hole 41 is not limited to a specific configuration. It can be made the same form as the conventional bottom blow plug 4. In this embodiment, it is formed (partitioned) by a pipe (pipe) embedded in a state of penetrating the main body 40. The conduit may penetrate through the main body 40 and protrude to the inside of the furnace body 1.
Preferably, the through hole 41 is provided in the central portion 42 of the main body 40.

Even if it is a form which has a plurality of penetration holes 41 in main part 40 (a plurality of penetration holes 41 shown in Drawing 4), a form (a penetration hole shown in Drawing 5) which has one penetration hole 41 41 may be in one form or in any form. Preferably, a plurality of through holes 41 are provided.

When the plurality of through holes 41 are provided, the arrangement of the through holes 41 is not limited. It is preferable to arrange at predetermined intervals (equal intervals). Further, the diameter of each through hole 41 and the like are not limited. The through holes 41 having different diameters may be disposed, or the through holes 41 having the same diameter may be disposed. Preferably it is the same diameter.
(effect)

The furnace body 1 of the present embodiment is formed into a predetermined shape, which is arranged along the radial direction and the circumferential direction on the bottom surface and the furnace shell 2 having a circular bottom that forms the outer shell of the furnace body 1 such as a converter. Bottom-blowing plug 4 provided with a laying brick 3 made of a fireproof material, a main body 40 made of a fireproof material formed larger than the laying brick 3, and a through hole 41 provided penetrating the body 40 And. The body portion 40 has an outer peripheral shape having a trapezoidal shape in which the inner diameter side in the radial direction is an upper base and the outer diameter side is a lower base, the upper base is concave to the outer diameter side, and the lower base is convex to the outer diameter side It has become.

According to this configuration, the upper bottom on the inner diameter side of the inner circumference in the radial direction of the main body 40 and the lower base on the outer circumference side in the radial direction are respectively expanded radially outward, and are opposed to the respective surfaces It is possible to reduce the gap between the laying bricks. As a result, it is not necessary to use conventional adjustment bricks. In the furnace body 1 of this embodiment, the conventional adjustment brick is not used, and the furnace body 1 is excellent in the assemblability of the laying brick 3 and the bottom blow plug 4.

According to the present embodiment, the upper bottom surface 40a and the lower bottom surface 40b of the main body 40 have either a smooth arc shape or a shape having corner portions. Since the upper bottom surface 40a and the lower bottom surface 40b of the main body 40 have these shapes, it is possible to reliably reduce the gap with the laying brick 3 positioned radially inward and radially outward.

According to the present embodiment, the main body 40 has a shape in which the upper bottom surface 40 a has a smooth arc shape and the lower bottom surface 40 b has a corner. With the upper bottom surface 40a and the lower bottom surface 40b of the main body portion 40 having these shapes, the gap with the laying bricks located radially outward can be reliably reduced. In particular, the gap between the lower bottom surface 40b located radially outward with a large radius of curvature and the laying brick 3 located radially outward can be reliably reduced.

The bottom-blowing plug 4 of this embodiment is disposed between the laying bricks 3 made of a refractory material formed in a predetermined shape and arranged along the radial and circumferential directions on the bottom of the furnace body 1 having a circular bottom such as a converter. A bottom blowing plug 4 to be installed, which is provided with a main body 40 made of a fireproof material formed to be larger than the laying brick 3 and a through hole 41 provided penetrating the main body 40; Has a trapezoidal outer shape in which the inner diameter side in the radial direction is the upper base and the outer diameter side is the lower base, the upper base is concave toward the outer diameter side, and the lower base is convex toward the outer diameter side It is characterized by

According to this configuration, the upper bottom and the lower bottom of the trapezoidal main body 40 are deformed to the outer diameter side, and a gap with the laying brick 3 disposed radially inward and radially outward. Can be made smaller and it is not necessary to use conventional adjustment bricks. That is, it can assemble | attach to the furnace 1 without using the conventional adjustment brick, and the problem of the fall of the assemblability which arises by having used the adjustment brick does not arise. That is, the bottom blowing plug 4 of the present embodiment is excellent in the assemblability to the furnace body 1.

According to the present embodiment, the upper and lower bases of the main body portion 40 have a shape that substantially matches the inscribed circle or the circumscribed circle of the facing surface of the laying brick 3 facing in the radial direction. Specifically, the upper bottom (upper bottom surface 40a) of the main body 40 has a shape substantially corresponding to the circumscribed circle of the facing surface of the laying brick 3 opposite in the radial direction, and the lower bottom (lower bottom surface 40b) of the main body 40 ) Is a shape that substantially matches the inscribed circle of the facing surface of the laying brick 3 facing in the radial direction. According to this configuration, when the bottom blowing plug 4 is assembled, the gap between the laying bricks 3 positioned on the inner diameter side and the outer diameter side can be reliably reduced.

According to the present embodiment, the upper and lower bases of the main body 40 of the bottom blowing plug 4 have either a smooth arc shape or a shape having a corner. Since the upper bottom surface 40a and the lower bottom surface 40b of the main body 40 have these shapes, it is possible to reliably reduce the gap with the laying brick 3 positioned radially inward and radially outward.

According to the present embodiment, the main body portion 40 of the bottom blowing plug 4 has a shape in which the upper base has a smooth arc shape and the lower base has a corner. With the upper bottom surface 40a and the lower bottom surface 40b of the main body portion 40 having these shapes, the gap with the laying bricks located radially outward can be reliably reduced. In particular, the gap between the lower bottom surface 40b located radially outward with a large radius of curvature and the laying brick 3 located radially outward can be reliably reduced.
[Modified form]

In the above embodiment, one form of the bottom blowing plug 4 is specifically shown, but as shown in FIG. 1 to FIG. 2, in the case where a plurality of bottom blowing plugs 4 are provided, each bottom blowing plug The size of 4 may be different. For example, as shown in FIG. 2, when the radial position is different, the size of the bottom blow plug 4 may be different. The size of the bottom blowing plug 4 corresponds to the size of the main body 40.

In addition, in the case where the plurality of bottom blowing plugs 4 are provided, the through holes 41 of the respective bottom blowing plugs 4 can be set arbitrarily as well. That is, it is formed in each bottom blow plug 4 so that the target gas can be blown into the inside of the furnace body 1. For example, even if the hole diameter of the through hole 41 is different for each bottom blowing plug 41, even if the number of the plurality of through holes 41 is different for each bottom blowing plug 41, these are combined It may be.

Moreover, in said embodiment, although the structure which arranged the laying brick 3 and the bottom blowing plug 4 in the bottom face 2a of the furnace shell 2 was shown, the joining which joins both between the laying brick 3 and the bottom blowing plug 4 It is good also as composition arranged material (composed of fixed form or unshaped form refractory material). Similarly, a bonding material (made of a fixed or unshaped refractory material) may be disposed between the laying brick 3 and the bottom blowing plug 4 and the bottom surface 2 a of the furnace shell 2.
Moreover, a plurality of layers may be formed on the bottom surface 2 a of the furnace shell 2 also for the laying brick 3.

1: furnace body 2: furnace body iron skin 3: laying brick 4: bottom blow plug 40: main body 41: through hole

Claims

A furnace shell having a circular bottom that forms an outer shell of a furnace such as a converter,
A laying brick made of a refractory material molded in a predetermined shape, arranged along the radial direction and the circumferential direction on the bottom surface,
A bottom-blowing plug including a main body made of a refractory material formed larger than the laying brick, and a through hole provided through the main body;
A furnace body having
The main body portion has an outer peripheral shape having a trapezoidal shape in which the inner diameter side in the radial direction is the upper base and the outer diameter side is the lower base,
A furnace body characterized in that the upper base is concave to the outer diameter side and the lower base is convex to the outer diameter side.
The furnace body according to claim 1, wherein the upper bottom and the lower bottom of the main body have either a smooth arc shape or a shape having a corner.
The furnace body according to any one of claims 1 to 2, wherein the main body portion has a shape in which the upper base has a smooth arc shape and the lower base has a corner.
A bottom-blowing plug installed between laying bricks made of a refractory material molded in a predetermined shape, arranged along the radial direction and circumferential direction on the bottom surface of a furnace body having a circular bottom surface such as a converter,
The bottom-blowing plug includes a main body made of a refractory material formed to be larger than the laying brick, and a through hole provided through the main body,
The main body portion has an outer peripheral shape having a trapezoidal shape in which the inner diameter side in the radial direction is the upper base and the outer diameter side is the lower base,
A bottom-blowing plug characterized in that the upper base is concave to the outer diameter side and the lower base is convex to the outer diameter side.
The bottom-blowing plug according to claim 4, wherein the upper bottom and the lower bottom of the main body portion have a shape substantially coinciding with an inscribed circle or a circumscribed circle of the facing surface of the laying brick facing in the radial direction.
The bottom-blowing plug according to any one of claims 4 to 5, wherein the upper bottom and the lower bottom of the main body portion have any of a smooth arc shape and a shape having a corner.
The bottom-blowing plug according to any one of claims 4 to 6, wherein the main body portion has a shape in which the upper base has a smooth arc shape and the lower base has a corner.