JP6780115B2 - Furnace and bottom blowing plug - Google Patents

Description

The present invention relates to a furnace body and a bottom-blown plug provided with a bottom-blown plug in which molten metal such as molten steel is stored and gas is blown into the stored molten metal.

Conventionally, a converter has been used for processing molten steel. The converter stores molten steel inside the furnace body. At the bottom of the converter (furnace bottom), a bottom blowing plug for gas blowing is arranged, which is provided with a plurality of through holes through which gas passes. The bottom-blown plug supplies gas (an inert gas such as argon) to the molten steel from the bottom of the furnace through the through hole to stir the molten steel. By this stirring, the temperature and composition of the molten steel in the furnace are made uniform and cleaned. The same process is performed not only in the converter but also in the furnace body provided with the bottom blowing plug.
As a furnace body for storing molten steel having such a bottom-blown plug, for example, Patent Document 1 (Japanese Unexamined Patent Publication No. 11-217613) is described.
In Patent Document 1 (Japanese Unexamined Patent Publication No. 11-217613), a furnace body iron skin, a refractory brick lined in the furnace body iron skin, and a bottom blowing nozzle (bottom blowing plug) provided on the bottom of the furnace are described. (Also referred to as), and the furnace body provided with.

In general, refractory bricks (also referred to as paving bricks) have a predetermined shape and are arranged on the surface of the iron skin of the furnace body in a radial direction and a circumferential direction at the bottom of the furnace. As a predetermined shape of the refractory brick, a shape in which the outer peripheral shape when the furnace bottom is viewed from the inside of the furnace is a square shape to a substantially trapezoidal shape with a wide outer diameter side can be mentioned.

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

Japanese Unexamined Patent Publication No. 11-217613

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

As described above, in the conventional furnace body, when arranging the bottom blowing nozzle using the main body portion, the adjusting brick is required separately from the refractory brick. The adjusting brick had to have a shape corresponding to the main body, and the outer peripheral shape of the adjusting brick was different, so that the assembling property was deteriorated. As a result, in the conventional furnace body using the adjusting brick, there is a problem that the assembling property of the refractory brick and the bottom blowing plug is lowered.
The present invention has been made in view of the above circumstances, and is an excellent assembling property of a paving brick (refractory brick) and a bottom blowing plug (bottom blowing nozzle), and a bottom blowing having excellent assembling property to the furnace body. The challenge is to provide a plug.

The furnace body of the present invention for solving the above problems is a predetermined furnace body having a circular bottom surface forming the outer shell of a furnace body such as a converter, and arranged on the bottom surface along the radial and circumferential directions. A bottom-blown plug having a paving brick made of a fire-resistant material molded into a shape, a main body made of a fire-resistant material formed larger than the paving brick, and a through hole provided through the main body. The main body has a trapezoidal outer peripheral shape in which the inner diameter side in the radial direction forms the upper bottom and the outer diameter side forms the lower base, and the upper bottom is the outer peripheral surface of the facing paving bricks. It has a smooth arc shape that roughly coincides with the circumscribing circle and is concave on the outer diameter side, and the lower bottom is convex with a corner on the outer diameter side that roughly coincides with the inner peripheral surface of the facing paving brick. It is a feature.

According to this configuration, the upper and lower bases of the trapezoidal main body are deformed to the outer diameter side, and the gap between the bricks located in the radial direction and the radial direction is reduced. And eliminates the need for traditional adjustment bricks. That is, the furnace body can be formed without using the conventional adjusting bricks, and the problem of deterioration of the assembling property caused by using the adjusting bricks does not occur. As a result, the furnace body of the present invention is a furnace body having excellent assembling property of the refractory brick and the bottom blowing plug.

According to the present invention, the main body has a shape in which the upper base has a smooth arc shape and the lower base has corners . By forming each of the upper bottom and the lower bottom in this shape, it is possible to surely reduce the gap (distance between the facing surfaces) with the paving bricks located inward in the radial direction and outward in the radial direction. It is possible to assemble without arranging bricks of a special shape like the adjustment bricks of.

The bottom-blown plug of the present invention for solving the above problems is a laying made of a fire-resistant material molded into a predetermined shape arranged along the radial and circumferential directions on the bottom surface of a furnace body having a circular bottom surface such as a converter. It is a bottom-blown plug installed between bricks, and the bottom-blown plug is provided with a main body made of a fireproof material formed larger than the laid brick and a through hole provided through the main body. The main body has a trapezoidal outer peripheral shape with the inner diameter side in the radial direction forming the upper bottom and the outer diameter side forming the lower base, and the upper bottom is smooth so as to substantially match the circumscribed circle on the outer peripheral surface of the facing paving brick. It is characterized in that it is arcuate and concave on the outer diameter side, and the lower bottom is convex in a shape having a corner on the outer diameter side that substantially coincides with the inner peripheral surface of the facing paving brick .

According to this configuration, the upper and lower bases of the trapezoidal main body are deformed to the outer diameter side, and the gap between the bricks arranged in the radial direction and the radial direction is small. It can be done and it is not necessary to use conventional adjusting bricks. That is, it can be assembled to the furnace body without using the conventional adjusting bricks, and the problem of deterioration of the assembling property caused by using the adjusting bricks does not occur. As a result, the bottom-blown plug of the present invention is excellent in assembling property to the furnace body.

According to the present invention, the upper base and the lower base of the main body portion have a shape that substantially coincides with the inscribed circle or the circumscribed circle of the facing surfaces of the paving bricks facing each other in the radial direction . According to this configuration, when the bottom blowing plug is assembled, the gap between the inner diameter side and the paving bricks located on the outer diameter side can be surely reduced.

According to the present invention, the main body has a shape in which the upper base has a smooth arc shape and the lower base has corners . By forming each of the upper bottom and the lower bottom in this shape, it is possible to surely reduce the gap (distance between the facing surfaces) with the paving bricks located inward in the radial direction and outward in the radial direction. It is possible to assemble to the furnace body without arranging bricks with a special shape like the adjustment bricks.

It is sectional drawing which shows the structure of the furnace body of an embodiment. It is a top view which shows the bottom surface of the furnace body of an embodiment. It is a top view which shows the structure of the vicinity of the bottom blowing plug in the furnace body of an embodiment. It is a top view which shows the structure of the bottom blowing plug of an 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 with reference to embodiments.
[Embodiment]
This embodiment is a furnace body provided with a bottom blowing plug 4 on the bottom of the furnace. The furnace body 1 of this embodiment is used for a converter.
As shown in the cross-sectional view of FIG. 1, the furnace body 1 of this embodiment has a furnace body iron skin 2, a paving brick 3, and a bottom-blown plug 4.
As shown in FIG. 1, the furnace body iron skin 2 forms the outer shell of the furnace body 1. The furnace body iron skin 2 has a circular bottom surface 2a. The furnace body iron skin 2 can have the same structure as the iron skin used in the conventional furnace body.

The paving brick 3 partitions the space inside the converter for storing molten metal such as molten steel.
The paving brick 3 is molded into a predetermined shape. The predetermined shape of the paving brick 3 is a columnar shape having a constant outer peripheral shape in the axial direction. As shown in FIGS. 2 to 3, the paving brick 3 has a trapezoidal end face shape (also referred to as an outer peripheral shape) in which the inner diameter side is the upper bottom and the outer diameter is the lower bottom. In the trapezoidal shape of the paving brick 3, the upper base and the lower base are parallel to each other. In FIG. 2, the state in which the paving bricks 3 are arranged in the circumferential direction is shown by concentric circles. In FIG. 3, the circumferential direction in which the paving bricks 3 are arranged in the circumferential direction is shown by a broken line. The cross-sectional view of FIG. 1 corresponds to the cross-sectional view taken along the line II in FIG.
The paving bricks 3 are arranged on the bottom surface 2a of the furnace body iron skin 2 along the radial direction and the circumferential direction. As shown in FIGS. 2 to 3, the arrangement is performed with the upper base located on the inner diameter side and the lower base located on the outer diameter side. Note that FIGS. 2 to 3 schematically show that the paving bricks 3 are arranged along the circumferential direction, and the boundaries of the paving bricks 3 are omitted.
The material of the paving brick 3 is not limited. The same material as the paving bricks used in conventional converters can be used. For example, a highly durable magnesia-carbon material can be used.

The bottom-blown plug 4 includes a main body 40 made of a refractory material formed larger than the paving brick 3 and a through hole 41 provided so as to penetrate the main body 40. The main body 40 has a trapezoidal outer peripheral shape in which the inner diameter side in the radial direction forms the upper bottom and the outer diameter side forms the lower bottom. This outer peripheral shape is the outer peripheral shape when the end surface of the bottom blowing plug 4 is viewed in the axial direction of the through hole 41, and is the 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 trapezoidal upper bottom is concave on the outer diameter side, and the lower bottom surface 40b corresponding to the trapezoidal lower bottom is convex on the outer diameter side. The upper bottom surface 40a and the lower bottom surface 40b are connected by a pair of side surface surfaces 40c and 40c corresponding to the side surfaces connecting the trapezoidal upper bottom surface and the lower bottom surface. The pair of side surfaces 40c and 40c are flat so that the corresponding trapezoidal shapes are linear. The trapezoidal shape that is the outer peripheral shape of the main body 40 includes a substantially trapezoidal shape in which the upper bottom surface 40a and the lower bottom surface 40b are not parallel to each other. In the bottom blowing plug 4, gas from the outside is blown into the molten metal stored in the furnace body 1 through the through hole 41.

The main body 40 of the bottom blowing plug 4 is made of a refractory material formed larger than the paving brick 3. The term "larger than the paving brick 3" in the main body 40 means that the trapezoidal shape of the outer peripheral shape of the main body 40 is larger than the trapezoidal shape of the paving brick 3.

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

The main body 40 has an upper bottom surface 40a facing the outer peripheral surface 3b of two (one or more, a plurality) bricks 3. The upper bottom surface 40a of the main body 40 has a shape that is concave outward in the radial direction, and more specifically, the upper bottom surface of the corresponding trapezoidal shape is formed so as to form a smooth arc shape. The arc shape of the upper bottom surface 40a is an arc shape that substantially coincides with the circumscribed circle of the outer peripheral surface 3b of the two paving bricks 3 facing the upper bottom surface 40a.

The main body 40 faces the inner peripheral surface 3a of the paving brick 3 having four lower bottom surfaces 40b (a plurality of numbers larger than the upper bottom surface 40a). 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 corners (specifically, a shape having three corners). .. The curved shape of the lower bottom surface 40b is a shape that substantially coincides with the inner peripheral surface 3a of the four paving bricks 3 facing the lower bottom surface 40b. The circumscribed circle of the lower bottom surface 40b coincides with the inscribed circle of the inner peripheral surface 3a of the four paving bricks 3 facing the lower bottom surface 40b.

The pair of linear side surfaces 40c, 40c form a linear shape that coincides with similar side surfaces 3c, 3c of the trapezoidal paving brick 3. In the present embodiment, the lengths of the pair of linear side faces 40c and 40c coincide with the length of the three paving bricks 3 arranged in the radial direction.

The through hole 41 is formed through the main body 40. In the through hole 41, the gas when the gas from the outside is blown into the inside of the furnace body 1 flows 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 hole 41 is formed in the same manner as the through hole through which gas flows in the conventional bottom blowing plug 4. That is, the through hole 41 is not limited to a specific configuration. It can have the same form as the conventional bottom blowing plug 4. In this embodiment, it is formed (partitioned) by a pipeline (pipe) buried in a state of penetrating the main body 40. The pipeline may penetrate the main body 40 and project to the inside of the furnace body 1.
The through hole 41 is preferably provided in the central portion 42 of the main body portion 40.

Even if the main body 40 has a plurality of through holes 41 (a plurality of through holes 41 shown in FIG. 4), a form having one through hole 41 (a through hole shown in FIG. 5). 41 may be one form) or any. A form having a plurality of through holes 41 is preferable.

When having a plurality of through holes 41, the arrangement of each through hole 41 is not limited. It is preferable to arrange them at predetermined intervals (equal intervals). Further, the hole diameter of each through hole 41 is not limited. Through holes 41 having different diameters may be arranged, or through holes 41 having the same diameter may be arranged. It is preferably the same diameter.
(effect)

The furnace body 1 of this embodiment is molded into a predetermined shape, which is arranged on the bottom surface along the radial direction and the circumferential direction with the furnace body iron skin 2 having a circular bottom surface forming the outer shell of the furnace body 1 such as a converter. A bottom-blown plug 4 having a paving brick 3 made of a fire-resistant material, a main body 40 made of a fire-resistant material formed larger than the paving brick 3, and a through hole 41 provided through the main body 40. And have. The main body 40 has a trapezoidal outer peripheral shape in which the inner diameter side in the radial direction forms the upper base and the outer diameter side forms the lower base, the upper bottom is concave on the outer diameter side, and the lower bottom is convex on the outer diameter side. It has become.

According to this configuration, the upper base on the inner diameter side of the inner circumference of the main body 40 in the radial direction and the lower base on the outer peripheral side in the radial direction each have a shape bulging outward in the radial direction and face each surface. The gap between the floor and the brick can be reduced. As a result, it is not necessary to use conventional adjusting bricks. In the furnace body 1 of this embodiment, the conventional adjusting brick is not used, and the furnace body 1 is excellent in assembling property of the paving brick 3 and the bottom blowing plug 4.

According to this 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 corners. By forming the upper bottom surface 40a and the lower bottom surface 40b of the main body portion 40 into these shapes, it is possible to surely reduce the gap between the paving bricks 3 located inward in the radial direction and outward in the radial direction.

According to this embodiment, the main body 40 has a shape in which the upper bottom surface 40a has a smooth arc shape and the lower bottom surface 40b has corners. By forming the upper bottom surface 40a and the lower bottom surface 40b of the main body portion 40 into these shapes, it is possible to surely reduce the gap between the upper bottom surface 40a and the lower bottom surface 40b located outward in the radial direction. In particular, the gap between the lower bottom surface 40b located on the outer side in the radial direction having a large radius of curvature and the paving brick 3 located on the outer side in the radial direction can be surely reduced.

The bottom-blown plug 4 of this embodiment is formed between paving bricks 3 made of fire-resistant material molded into a predetermined shape, arranged along the radial and circumferential directions on the bottom surface of a furnace body 1 having a circular bottom surface such as a converter. The bottom-blown plug 4 to be installed includes a main body 40 made of a fire-resistant material formed larger than the paving brick 3 and a through hole 41 provided through the main body 40. Has a trapezoidal outer peripheral shape in which the inner diameter side in the radial direction forms the upper base and the outer diameter side forms the lower base, the upper bottom is concave on the outer diameter side, and the lower bottom is convex on the outer diameter side. It is characterized by that.

According to this configuration, the upper and lower bases of the trapezoidal main body 40 are deformed to the outer diameter side, and the gap between the trapezoidal main body 40 and the paving bricks 3 arranged in the radial direction and the outer diameter direction is formed. Can be made smaller, eliminating the need for traditional adjustment bricks. That is, it can be assembled to the furnace body 1 without using the conventional adjusting bricks, and the problem of deterioration of the assembling property caused by using the adjusting bricks does not occur. That is, the bottom-blown plug 4 of this embodiment is excellent in assembling property to the furnace body 1.

According to this embodiment, the upper bottom and the lower bottom of the main body 40 have a shape substantially matching the inscribed circle or the circumscribed circle of the facing surfaces of the paving bricks 3 facing each other in the radial direction. Specifically, the upper bottom (upper bottom surface 40a) of the main body 40 has a shape that substantially coincides with the circumscribed circles of the facing surfaces of the paving bricks 3 facing each other in the radial direction, and the lower bottom (lower bottom surface 40b) of the main body 40. ) Is a shape that substantially coincides with the inscribed circle of the facing surface of the paving brick 3 facing in the radial direction. According to this configuration, when the bottom blowing plug 4 is assembled, the gap between the inner diameter side and the laying brick 3 located on the outer diameter side can be surely reduced.

According to this embodiment, the upper bottom and the lower bottom of the main body 40 of the bottom blowing plug 4 have either a smooth arc shape or a shape having corners. When the upper bottom surface 40a and the lower bottom surface 40b of the main body 40 have these shapes, the gap between the paving bricks 3 located inward in the radial direction and outward in the radial direction can be surely reduced.

According to this embodiment, the main body 40 of the bottom blowing plug 4 has a shape in which the upper bottom has a smooth arc shape and the lower base has corners. By forming the upper bottom surface 40a and the lower bottom surface 40b of the main body portion 40 into these shapes, it is possible to surely reduce the gap between the upper bottom surface 40a and the lower bottom surface 40b located outward in the radial direction. In particular, the gap between the lower bottom surface 40b located on the outer side in the radial direction having a large radius of curvature and the paving brick 3 located on the outer side in the radial direction can be surely reduced.
[Transformed form]

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

Further, when a plurality of bottom blowing plugs 4 are provided, the through holes 41 of the bottom blowing plugs 4 can be arbitrarily set in the same manner. That is, it is formed in each bottom blowing 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, or if there are a plurality of through holes 41 and the number is different for each bottom blowing plug 41, these are combined. There may be.

Further, in the above embodiment, the paving brick 3 and the bottom blowing plug 4 are arranged on the bottom surface 2a of the furnace body iron skin 2, but the paving brick 3 and the bottom blowing plug 4 are joined together. It may be configured by arranging a material (consisting of a standard or irregular refractory material). Similarly, a bonding material (made of a fixed or amorphous refractory material) may be arranged between the paving brick 3 or the bottom blowing plug 4 and the bottom surface 2a of the furnace body iron skin 2.
Further, the paving brick 3 may also have a plurality of layers formed on the bottom surface 2a of the furnace body iron skin 2.

1: Furnace body 2: Furnace body Iron skin 3: Laying brick 4: Bottom blowing plug 40: Main body 41: Through hole

Claims (2)

A furnace body iron skin having a circular bottom surface that forms the outer shell of a furnace body such as a converter,
Brick made of refractory material molded into a predetermined shape arranged along the radial and circumferential directions on the bottom surface, and
A bottom-blown plug having a main body made of a refractory material formed larger than the paving brick and a through hole provided through the main body.
It is a furnace body with
The main body has a trapezoidal outer peripheral shape in which the inner diameter side in the radial direction forms the upper bottom and the outer diameter side forms the lower base.
The upper base has a smooth arc shape that substantially coincides with the circumscribed circle of the outer peripheral surface of the facing brick, and is concave on the outer diameter side, and the lower base substantially coincides with the inner peripheral surface of the facing brick. A furnace body characterized by having a corner on the radial side and being convex. A bottom-blown plug installed between bedding bricks made of refractory material molded into a predetermined shape, arranged along the radial and circumferential directions on the bottom surface of a furnace body having a circular bottom surface such as a converter.
The bottom-blown plug includes a main body made of a refractory material formed larger than the paving brick, and a through hole provided through the main body.
The main body has a trapezoidal outer peripheral shape in which the inner diameter side in the radial direction forms the upper bottom and the outer diameter side forms the lower base.
The upper base has a smooth arc shape that substantially coincides with the circumscribed circle of the outer peripheral surface of the facing brick, and is concave on the outer diameter side, and the lower base substantially coincides with the inner peripheral surface of the facing brick. A bottom-blown plug characterized by having a corner on the radial side and being convex.

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