JP2021161502A - Tilting trough - Google Patents

Abstract

To provide a tilting trough having standard bricks embedded in a castable manner and excellent in durability in the vicinity of the standard bricks which are subjected to hot metal.SOLUTION: A tilting trough 1 includes: a tiltable shallow bottom-container-like tilting trough body 2; a castable layer 5 composed of a castable material formed on the inner surface of the tilting trough body 2; and a hot metal part 3 buried in the castable layer 5 with the upper surface 30 exposed and subjected to the poured hot metal on the upper surface 30. The hot metal part 3 of the tilting trough 1 has a brick body part 31 composed of a standard brick made of a prescribed material which is subjected to the poured hot metal, and an outer peripheral block part 35 composed of a frame-like precast block made of a prescribed material in which the hot metal flows along the upper surface 36 and the brick body part 31 is fitted inside.SELECTED DRAWING: Figure 2

Description

The present invention relates to a tilting gutter.

For some time, a tilting gutter that receives the hot metal that has been tapped through the tapping gutter that extends from the blast furnace has been proposed. The tilting gutter tilts after receiving the hot metal, so that the received hot metal is put into a transport container such as a torpedo car or a hot metal pot.

The tilting gutter is formed by pouring a fluid castable material on site.

The tilting gutter is located lower than the outlet of the tapping gutter. Therefore, when the hot metal shifts to the tilting gutter, the part of the tilting gutter (hereinafter referred to as the "hot water contact part") on which the hot metal that has fallen from the ironing gutter lands is a castable material due to the heat of the hot metal or the impact of the falling hot metal. Damage is significant. As a result, the life of the tilting gutter is shortened, so that the hot water contact portion is required to have not only corrosion resistance but also wear resistance.

In response to this problem, Patent Document 1 discloses a tilting gutter in which a hot water contact portion that receives hot metal is made of a standard brick and the other portion is a castable material. That is, Patent Document 1 describes a tilting gutter in which a standard brick is embedded in a castable material.

Utility model registration No. 3197534

However, with the conventional tilting gutter, it has been difficult to increase the size of the standard brick due to manufacturing problems. In other words, it was difficult to protect the tilting gutter by forming the damaged area of the hot water contact part only with standard bricks.
Therefore, in the conventional tilting gutter, the castable material around the hot water contact portion is damaged in advance. When the castable material around the standard brick was damaged, the standard brick was heated from multiple surfaces by the hot metal and became fragile, and the damage was accelerated and the life of the tilting gutter was not significantly improved.
Not only that, the hot metal can be easily inserted into the contact portion (joint) between the castable material and the standard brick, and the hot metal can easily wrap around to the lower surface side of the standard brick.

Specifically, the hot metal hits the standard brick (hot water contact portion) and then flows from the upper surface of the standard brick along the upper surface of the castable material. If the hot metal continues to flow, the upper surface of the standard brick and castable material will wear.
The amount of wear is greater for materials with higher porosity. Since the castable material has a higher porosity than the standard brick, the castable material wears with a larger amount of wear than the standard brick. Due to this wear, the upper surface of the castable material is scooped out. As the castable material wears, the sides of the standard brick are exposed. The hot metal flowing in the tilting gutter in this state flows along the surface (upper surface and side surface) of the standard brick, and the hot metal invades the joints of the standard brick and the castable material. The hot metal that has entered the joint flows along the side surface of the standard brick and wraps around to the lower surface side of the standard brick. Then, the standard bricks will be lifted by the hot metal that wraps around. As a result, the standard bricks come off from the tilting gutter, leading to damage to the tilting gutter.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a gutter having excellent durability in the vicinity of a gutter that receives hot metal in a gutter in which a fixed brick is embedded in a castable.

The tilting gutter of the present invention that solves the above problems has a tiltable shallow-bottomed container-shaped tilting gutter main body, a castable layer made of a castable material formed on the inner surface of the tilting gutter main body, and a state in which the upper surface is exposed. It is a tilting gutter that is embedded in the castable layer and has a hot water contact part that receives the hot metal to be poured on the upper surface, and the hot water contact part is an alumina-magnesia-carbon system, alumina-silicon carbide- A brick body made of standard bricks made of either magnesia-carbon or alumina-silicon carbide-waxite-carbon, and hot metal flows along the upper surface and the brick body fits inside. It is characterized by having an outer peripheral block portion made of a frame-shaped precast block made of an alumina-spinel-silicon carbide-based material.

The tilting gutter of the present invention has an outer peripheral block portion made of a precast block having a higher porosity than the brick main body but a lower porosity than the castable material on the outer periphery of the brick main body to which the hot metal to be poured hits. With this configuration, damage to the joints between the brick main body and the outer peripheral block can be reduced, and insertion of the hot metal into the joints can be reduced, and the floating of the brick main body can be suppressed. As a result, damage to the hot water contact portion is reduced, and the durability of the tilting gutter is improved.

It is a top view of the tilting gutter of the embodiment. It is a cross-sectional view taken along the line II-II in FIG. It is a cross-sectional view taken along the line III-III in FIG. It is a top view which shows the hot water contact part of the tilting gutter of Embodiment 1. It is a cross-sectional view taken along the line VV in FIG. It is a cross-sectional view taken along the line VI-VI in FIG. It is a figure which shows the structure in the case where the tilting gutter of an embodiment is used for a blast furnace. It is an enlarged cross-sectional view which shows the vicinity of the hot water contact part of the conventional tilting gutter. It is an enlarged cross-sectional view which shows the vicinity of the hot water contact part of the conventional tilting gutter.

Hereinafter, the tilting gutter of the present invention will be specifically described using the embodiments. It should be noted that the embodiment shows one embodiment for specifically explaining the present invention, and the present invention is not limited to the embodiment.

[Embodiment]
The tilting gutter 1 of this embodiment has the configuration shown in FIGS. 1 to 7. FIG. 1 is a top view of the tilting gutter 1 of the present embodiment. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. FIG. 4 is a top view of the hot water contact portion. FIG. 5 is a cross-sectional view taken along the line VV in FIG. FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. FIG. 7 is a schematic configuration diagram when the tilting gutter 1 of this embodiment receives hot metal from a blast furnace.

In the tilting gutter 1 of the first embodiment, as shown in FIG. 7, the hot metal ejected from the blast furnace 60 functioning as a blast furnace 60 passes through the large gutter 61 and the middle gutter 62 as the tapping gutter, and the tip outlet 63 of the middle gutter 62. Pour from and receive the poured hot metal. The tilting gutter 1 that has received the hot metal transfers the hot metal to a desired hot metal pan 64, a torpedo car (not shown), or the like by tilting the left and right ends of FIG. 7. The tilting gutter 1 is arranged so as to receive the hot metal poured from the tip outlet 63 of the middle gutter 62.

As shown in FIGS. 1 to 3, the tilting gutter 1 of the present embodiment includes a tilting gutter main body portion 2, a hot water contact portion 3, and a castable layer 5.

The tilting gutter main body 2 forms the outer peripheral shape of the tilting gutter 1. The tilting gutter main body 2 is made of an iron (heat-resistant metal) member (also referred to as an iron skin) having a bottom surface and forming a shallow container shape. The shallow-bottomed container shape having a bottom surface means a substantially tank-like shape with an opening at the top. The tilting gutter main body 2 has a shape extending in the longitudinal direction (left-right direction in FIG. 1).

The tilting gutter main body 2 is provided with a castable layer 5 in substantially the entire area of the inner surface of the tank. The tilting gutter main body 2 includes an inclined surface portion 20 and 21 whose surface rises and inclines toward the tip in the longitudinal direction, and a horizontal surface portion 22 located between the two inclined surface portions 20 and 21 and extending in the horizontal direction. Is formed. As shown in FIG. 3, the tilting gutter main body 2 has an inner peripheral shape in which the cross section in a plane perpendicular to the longitudinal direction is recessed in a substantially U shape (or a substantially concave shape) capable of forming the castable layer 5. And has an outer peripheral shape.

As shown in FIG. 2, the tilting gutter main body 2 has hot metal discharge ports 25 formed at both ends 23 and 24 in the longitudinal direction. The tilting gutter main body 2 is provided so that one end 23 can be tilted in the directions of arrows A1 and A2 and the other end 24 can be tilted in the directions of arrows B1 and B2.

The tilting gutter main body 2 is connected to and fixed to a moving means (not shown) and moves to a predetermined position. The moving means of this embodiment also serves as a tilting means for tilting both end portions 23 and 24 of the tilting gutter main body portion 2.

The castable layer 5 is a member made of a castable material formed on the inner surface of the tilting gutter main body 2. The castable layer 5 is formed by casting and molding a fluid castable material containing a refractory as a main component. The castable layer 5 partitions the flow path 50 (substantially groove-shaped flow path) through which the hot metal flows in the tilting gutter 1.

As shown in FIG. 2, the flow path 50 is partitioned on both ends in the longitudinal direction by inclined surfaces 51 and 52 that are inclined corresponding to the inclined surfaces 20 and 21 of the tilting gutter main body 2. The inclined surfaces 51 and 52 are surfaces whose surfaces rise toward the hot metal discharge port 25. Tip surfaces 54 and 55 are formed on the tip sides of the inclined surfaces 51 and 52, respectively, whose surfaces descend toward the hot metal discharge port 25 and incline. The inclined surface 51 is connected to the tip surface 54, and the inclined surface 52 is connected to the tip surface 55. At the central portion in the longitudinal direction, a horizontal plane 53 extending in the horizontal direction is formed corresponding to the horizontal plane portion 22 of the tilting gutter main body portion 2.
As shown in FIG. 3, the flow path 50 has an inner peripheral surface of the castable layer 5 formed so as to form a substantially concave shape in which the upper portion opens wider than the bottom portion in a cross section perpendicular to the longitudinal direction. The flow path 50 is partitioned from a bottom surface and a pair of side surfaces, and each surface is a flat surface.

As shown in FIGS. 1 and 2, the hot water contact portion 3 has an upper surface 30 thereof in a central region in the longitudinal direction of the tilting gutter main body portion 2 (specifically, a region corresponding to the horizontal plane 53 of the castable layer 5). It is integrally embedded in the castable layer 5 in an exposed state. The hot water contact portion 3 is located between the inclined surfaces 51 and 52. The upper surface 30 of the hot water contact portion 3 has the same plane as the horizontal plane 53 of the castable layer 5.
As shown in FIGS. 4 to 6, the hot water contact portion 3 includes a brick main body portion 31 and an outer peripheral block portion 35. The outer peripheral shape of the hot water contact portion 3 is formed by the outer peripheral block portion 35.

The brick body 31 is made of a standard brick. A standard brick is a brick formed by compression molding and firing a material. The shape of the standard brick forming the brick body 31 is not limited. In this embodiment, as shown in FIGS. 4 to 6, the upper surface 32 to which the hot metal hits has a frustum shape (a substantially rectangular plate shape as a whole, a substantially square pyramid shape) smaller than the lower surface 33. The brick main body 31 is partitioned by an upper surface 32 to which the hot metal to be poured hits, a lower surface 33 facing the upper surface 32, and four side surfaces 34 connecting the upper surface 32 and the lower surface 33. In this embodiment, the upper surface 32 and the lower surface 33 form parallel planes at positions where the centers (centers of gravity) overlap. Further, the area of the lower surface 33 is larger than the area of the upper surface 32. That is, the brick main body 31 has a cross section along the plate thickness direction (cross-sectional shape shown in FIGS. 5 to 6) and is formed so as to form a substantially trapezoidal shape. At this time, the four side surfaces 34 form inclined surfaces inclined with respect to the plate thickness direction so as to connect the upper surface 32 and the lower surface 33.
The specific dimensions of the brick body 31 (for example, the shape and area of the upper surface 32 and the lower surface 33, and the plate-like plate thickness) are not limited. Any shape may be used as long as it can form an upper surface 32 capable of receiving the hot metal poured into the tilting gutter 1.

The shapes of the upper surface 32 and the lower surface 33 are not limited, and a circular shape, an elliptical shape, or a polygonal shape can be given as a whole, and a square shape is preferable. Further, in the case of a shape having corners, it is preferable that each corner is rounded.

In this embodiment, the upper surface 32 and the lower surface 33 have a square shape. The length of one side of the upper surface 32 is 90% of the length of one side of the lower surface 33. The square corners of the upper surface 32 and the lower surface 33 have an R shape (rounded) in order to suppress damage during thermal expansion and contraction. The distance between the upper surface 32 and the lower surface 33 (thickness of the hot water contact portion 3) is 50% of the length of one side of the lower surface 33. The square shape of the lower surface 33 has rounded corners, and forms an R shape with a radius of curvature of 10% of the length of one side.

As shown in FIGS. 4 to 6, the outer peripheral block portion 35 is made of a frame-shaped (annular) precast block into which the brick main body portion 31 is fitted. A precast block is a block formed by compression molding a material. The frame-shaped shape of the outer peripheral block portion 35 indicates that the shape is an annular shape as a whole (a shape in which the ring is not cut in the circumferential direction). The outer peripheral block portion 35 has an upper surface 36 that contacts the flowing hot metal, a lower surface 37 that faces the upper surface 36, outer peripheral surfaces 39 and 40 that connect the upper surface 36 and the lower surface 37, and an inner circumference that connects the upper surface 36 and the lower surface 37. It has a surface 38 and.

As shown in FIGS. 5 to 6, the outer peripheral block portion 35 has a shape in which the frame-shaped (annular) inner peripheral surface 38 coincides with the side surface 34 of the brick main body portion 31. That is, the outer peripheral block portion 35 has four inner peripheral surfaces 38 that are in close contact with the four side surfaces 34 of the brick main body portion 31. The inner peripheral surface 38 of the outer peripheral block portion 35 is in close contact with the side surface 34 of the brick main body portion 31 without a gap.

As shown in FIG. 4, the outer peripheral block portion 35 of this embodiment has a substantially rectangular shape as a whole when the upper surface 36 is viewed from above (a substantially rectangular shape having a long side in the longitudinal direction of the tilting gutter main body portion 2). ) Is in a ring.
The frame-shaped upper surface 36 and lower surface 37 (both end surfaces in the annular axial direction) of the outer peripheral block portion 35 form parallel planes. When the brick body portion 31 is fitted inside the outer peripheral block portion 35 (the axial center of the ring) to form the hot water contact portion 3, the upper surface 36 is formed so that the upper surface 30 of the hot water contact portion 3 forms a flat surface. ing. That is, the upper surface 36 of the outer peripheral block portion 35 is located on a plane that coincides with the upper surface 32 of the brick main body portion 31 that fits inside. The lower surface 37 of the outer peripheral block portion 35 may or may not be formed in the same plane as the lower surface 33 of the brick main body portion 31. It is preferable that the two lower surfaces 33 and 37 form a flat surface.

In the outer peripheral block portion 35, the upper surface 36 and the lower surface 37 having a frame shape are connected by an inner peripheral surface 38 and an outer peripheral surface. The outer peripheral surface is composed of a side surface 39 corresponding to a rectangular long side and a side surface 40 corresponding to a short side.
In the outer peripheral block portion 35, the side surface 39 connecting the upper surface 36 and the lower surface 37 has an inclined surface inclined with respect to the vertical direction, similarly to the inner peripheral surface 38. The side surface 39 is inclined in the same direction as the inner peripheral surface 38 of the outer peripheral block portion 35.

In the outer peripheral block portion 35, the side surface 40 connecting the upper surface 36 and the lower surface 37 is provided with a step portion. The stepped portion includes surfaces 41 and 42 parallel to the upper surface 36 and the lower surface 37 (or at least one surface of the upper surface 36 and the lower surface 37, preferably the upper surface 36) in a cross section along the vertical direction. A portion where the side surfaces 43, 44, and 45 extending in the direction intersect to form an angle is shown. If at least one of the intersecting faces is curved, it indicates the intersection of tangents.
As shown in FIG. 5, the side surface 40 of the outer peripheral block portion 35 (that is, the hot water contact portion 3) has a substantially stepped cross-sectional shape. The broken line in FIG. 5 indicates the outer peripheral shape assumed when the shape is not substantially stepped. That is, the outer peripheral block portion 35 of the present embodiment has a shape that is missing from the assumed shape shown by the broken line.
Although this embodiment has two steps, the number of steps is not limited. It may be one stage or three or more stages. Two or more steps are preferable because the infiltration can be further suppressed when the hot metal invades the interface.

When the number of steps is two or more, the distance between the surfaces 41 and 42 substantially parallel to the upper surface 36 and the lower surface 37 and the width of the respective surfaces 41 and 42 may be the same or different. , Either way. When the number of steps is one or more, the distance between the respective surfaces 41 and 42 and the upper surface 36 and the lower surface 37 (distance between the surfaces in the vertical direction) is not limited.

The specific shape of the side surfaces 43, 44, 45 of the step portion is also not limited. In this embodiment, of the side surfaces 43, 44, 45 of the step portion, the side surface 45 connected to the lower surface forms an inclined surface. The side surface 43 connecting the upper surface 36 and the side surface 44 connecting the surfaces 41 and 42 form a plane extending in the vertical direction.

In the present embodiment, the hot water contact portion 3 in the state where the brick main body portion 31 is fitted to the outer peripheral block portion 35 has a substantially rectangular shape on the upper surface 30 and the lower surface, respectively. Specifically, the lower surfaces (lower surface 33 and lower surface 37) of the hot water contact portion 3 are 10% larger on both sides (20% in total length) than the brick main body portion 31 in the shape shown in FIG. In the shape shown in FIG. 5, it is 30% larger on both sides (60% in total length). The corners of the lower surface have an R shape rounded with a radius of curvature of 20% of the length of one side of the lower surface of the brick body 31.

The upper surface 30 (upper surface 32 and upper surface 36) of the hot water contact portion 3 is 10% larger on both sides (20% in total length) than the brick main body portion 31 in the shape shown in FIG. In the shape shown in FIG. 5, the upper surface 30 is 10% larger on both sides (20% in total length) than the brick main body 31.
The distance (thickness in the vertical direction) between the upper surface 36 and the lower surface 37 of the outer peripheral block portion 35 is formed to be the same as that of the brick main body portion 31.

The outer peripheral block portion 35 is provided with two step portions (two step portions) at both ends in the longitudinal direction. The substantially parallel surfaces 41 and 42 forming the two steps are each formed with a length in the longitudinal direction of 10% of one side of the lower surface of the brick body 31. The substantially parallel surfaces 41 and 42 are formed at positions of 1/3 (upper surface 32 to 1/3) and further 1/3 (upper surface 32 to 2/3) of the thickness of the hot water contact portion 3.

In the present embodiment, the step portion is formed only on the side surface 40 of the outer peripheral surface connecting the upper surface 36 and the lower surface 37, but may also be formed on the side surface 39. When the hot metal flows through the tilting gutter 1, the step portion is preferably formed on a side surface located downstream in the flow direction (a side surface extending along a direction intersecting the flow direction).

In the present embodiment, the hot water contact portion 3 has a residual dimensional change rate of 0.1% or more at 1400 ° C. × 5 hours under the reducing atmosphere of the brick main body portion 31 and the outer peripheral block portion 35, and the brick main body portion 31 has a residual dimensional change rate of 0.1% or more. The absolute value of the difference between the residual dimensional change rate and the residual dimensional change rate of the outer peripheral block portion 35 is 0.5% or less. The absolute value of the difference is more preferably 0.4% or less, and further preferably 0.3% or less.
The residual dimensional change rate indicates the rate of change in dimensions before and after heating to a predetermined temperature and then allowing to cool. The residual dimensional change rate is set to a predetermined temperature by placing a sample processed to 30 mm × 30 mm × 100 mm in a container filled with carbon-based powder and raising the temperature at 3 ° C. per minute using an electric furnace. The test is carried out by allowing it to cool, and the dimensions of the 100 mm portion before and after the test are measured.

When the residual dimensional change rate is 0.1% or more, even if both the brick main body 31 and the outer peripheral block 35 are allowed to cool after receiving heat, they expand more than before heating. As a result, the spread of the joints between the brick main body 31 and the outer peripheral block 35 is suppressed even after cooling, and even if the hot metal is received again, the infiltration of the hot metal into the joints can be suppressed.

If there is a difference in the rate of change in the remaining dimensions between the brick body 31 and the outer peripheral block 35, there will be a difference in the expanded dimensions of both 31 and 35 after heating and cooling, resulting in widening of joints and cracking of refractories. Causes damage due to. When the residual dimensional change rate of the outer peripheral block portion 35 is larger than that of the brick main body portion 31, if there is a difference in the residual expansion change rate, the outer peripheral block portion 35 has a larger dimension after heating and cooling, and the joint with the brick main body portion 31. Spreads. As a result, the hot metal easily penetrates into the joint. On the contrary, when the residual dimensional change rate of the outer peripheral block portion 35 is smaller than that of the brick main body portion 31, if there is a difference in the residual expansion change rate, the brick main body portion 31 has a larger dimension, so that the outer peripheral block portion 35 is pushed. The brick body 31 may crack and be damaged, or the brick body 31 may crack and peel off due to the binding force of the outer peripheral block 35. As a result, the expected durability cannot be obtained. Therefore, the absolute value of the difference in the residual dimensional change rate is preferably 0.5% or less.

The specific value of the residual dimensional change rate of each of the brick main body portion 31 and the outer peripheral block portion 35 is not limited. The residual dimensional change rate of the brick body 31 is preferably 0.1 to 1.0%, more preferably 0.4 to 0.6%. The residual dimensional change rate of the outer peripheral block portion 35 is preferably 0.1 to 1.0%, more preferably 0.4 to 0.7%.

The brick main body 31 of the hot water contact portion 3 is made of a material having the above-mentioned characteristics of the residual dimensional change rate. This material is any one of alumina-magnesia-carbon type, alumina-silicon carbide-magnesia-carbon type, and alumina-silicon carbide-godite-carbon type.
The outer peripheral block portion 35 of the hot water contact portion 3 is made of a material having the above-mentioned characteristics of the residual dimensional change rate. This material is an alumina-spinel-silicon carbide based material.
These materials constituting the brick main body portion 31 and the outer peripheral block portion 35 have low reactivity with hot metal and have high corrosion resistance to hot metal. As a result, damage due to corrosion of the brick main body 31 and the outer peripheral block 35 is suppressed.

The brick body 31 is more preferably an alumina-silicon carbide-magnesia-carbon refractory. The alumina-silicon carbide-magnesia-carbon refractory has higher strength than the magnesia-carbon refractory and can exhibit high wear resistance. Alumina-silicon carbide-magnesia-carbon refractories are 70 to 80% alumina, 5.0 to 7.5% silicon carbide, 7.5 to 10.5% carbon, and 4 magnesia by mass ratio. It is preferably contained in an amount of 10%. Table 1 shows a composition example of the composition of the alumina-silicon carbide-magnesia-carbon refractory. In addition, in the compounding example shown in Table 1, a conventionally known additive is further included. “After heat reduction” in Table 1 indicates a state after heat treatment (1400 ° C. × 5 hours) in a reducing atmosphere for measuring the residual dimensional change rate. Porosity, bulk specific gravity, and compressive strength were each measured using a conventionally known measuring device.
As shown in Table 1, it is an alumina-silicon carbide-magnesia-carbon refractory, and the ratios of alumina, silicon carbide, magnesia, and carbon are within the above ranges. In Formulation Examples 10 to 12, the residual dimensional change rate is within a preferable range of 0.1 to 1.0%. In addition, compounding examples 1 and 9 are examples which deviate from the above range and compounding.

When the brick body 31 is an alumina-silicon carbide-godite-carbon refractory, the mass ratio is 65 to 74% for alumina, 5.0 to 7.5% for silicon carbide, and 5 for _{silica (SiO 2).} It is preferably contained in an amount of ~ 15% and carbon at 7.5 to 10.5%. Table 1 shows a composition example of the composition of the alumina-silicon carbide-godite-carbon refractory. Rouseki is a compound containing a silicate mineral, and is shown by the chemical composition ratio in Table 1. The formulation examples shown in Table 1 further contain conventionally known additives.
As shown in Table 1, compounding examples 5 to 5 which are alumina-silicon carbide-godite-carbon refractories in which the respective ratios of alumina, silicon carbide, pyrophyllite, and carbon are within the above ranges. In No. 8, the residual dimensional change rate is within a preferable range of 0.1 to 1.0%. In addition, compounding examples 1 and 9 are examples which deviate from the above range and compounding.

When the brick body 31 is an alumina-magnesia-carbon refractory, it is preferable that the brick body 31 contains 75 to 81% of alumina, 4 to 10% of magnesia, and 7.5 to 10.5% of carbon in terms of mass ratio. Table 1 shows a composition example of the composition of the alumina-magnesia-carbon refractory. The formulation examples shown in Table 1 further contain conventionally known additives.
As shown in Table 1, in compounding examples 13 to 14, which are alumina-magnesia-carbon refractories in which the ratios of alumina, magnesia, and carbon are within the above ranges, the residual dimensional change rate is high. It is in the preferable range of 0.1 to 1.0%. In addition, compounding examples 1 and 9 are examples which deviate from the above range and compounding.

The outer peripheral block portion 35 is made of an alumina-spinel-silicon carbide-based material. The outer peripheral block portion 35 preferably contains 5.0 to 35% of alumina, 5.0 to 25% of silicon carbide, and 40 to 80% of spinel by mass ratio. Table 2 shows typical composition examples of alumina-spinel-silicon carbide refractories. Spinel (MgAl ₂ O ₄ ) is a compound of alumina (Al ₂ O ₃ ) and magnesia (MgO), and is shown by the chemical composition ratio in Table 2. The formulation examples shown in Table 2 further include conventionally known additives.
As shown in Table 2, in the formulation example 16 which is an alumina-spinel-silicon carbide-based refractory in which the ratios of alumina, spinel (magnesia), and silicon carbide are within the above ranges, the residual dimensions are present. The rate of change is within a preferable range of 0.1 to 1.0%. In addition, compounding example 15 is an example outside the above range.

It is more preferable that the brick main body 31 is made of an alumina-silicon carbide-magnesia-carbon refractory (standard brick), and the outer peripheral block 35 is made of an alumina-spinel-silicon carbide refractory (precast block). Since the brick main body portion 31 and the outer peripheral block portion 35 are made of these materials, the brick main body portion 31 and the outer peripheral block portion 35 have the above-mentioned residual dimensional change rate.
The manufacturing method of the hot water contact portion 3 is not limited. It is possible to manufacture a standard brick having a predetermined shape and to mold a precast block in a state where the manufactured standard brick is arranged in a mold.

For example, alumina, silicon carbide, magnesia, carbon particles and powders, and other conventionally known additives are added and the soil is kneaded. Yes soil is put into a press machine, and the molded product obtained by pressure molding is dried (heat treated at a low temperature of 100 to 500 ° C.) to develop strength and then processed to form a standard brick (brick body 31). ) Is manufactured. The obtained standard brick is placed in a mold having a predetermined cavity, and each particle and powder of alumina, spinel, and silicon carbide and other conventionally known additives are added and kneaded, and the brick is poured into a mold to provide an outer circumference. The block portion 35 is molded. By drying the obtained molded product (heat treatment at a low temperature of 100 to 500 ° C.), the hot water contact portion 3 can be manufactured.
The hot water contact portion 3 is embedded in the castable layer 5 with the upper surface 30 exposed. By embedding the hot water contact portion 3 in the castable layer 5, the hot water contact portion 3 and the castable layer 5 are in close contact with each other without a gap.

The castable layer 5 is not limited to the material of the castable material, and is formed of, for example, an alumina-silicon carbide refractory. The castable layer 5 is more preferably an alumina-silicon carbide-silica refractory, and further preferably an alumina-silicon carbide-silica-carbon refractory. In this refractory, the mass ratio of each component is not limited, and in terms of mass ratio, alumina is 65 to 80%, silicon carbide is 10 to 30%, silica is 3 to 7%, and carbon is 1 to 5%. It is preferable to include it.

(Action and effect of this form)
The tilting gutter 1 of this embodiment is used as follows.
As shown in FIG. 7, hot metal is ejected from the blast furnace 60 located higher than the tilting gutter 1. The hot metal discharged from the blast furnace 60 flows down from the tip outlet 63 to the tilting gutter 1 via the large gutter 61 and the middle gutter 62, and is poured into the gutter 1.
The hot metal that has flowed down from the tip outlet 63 hits the upper surface 30 of the hot water contact portion 3 of the tilting gutter 1. Specifically, it corresponds to the upper surface 32 of the brick main body 31.

Then, the tilting gutter 1 is tilted by the operation of the tilting means (not shown). One end 23 of the tilting gutter 1 is tilted in the direction of arrow A1. That is, one end 23 is tilted downward and the other end 24 is tilted upward, so that the hot metal that hits the upper surface 32 of the brick main body 31 passes through the upper surface 36 of the outer peripheral block 35. Then, it flows in the flow path 50 toward the one end portion 23 that is lowered downward in the vertical direction from the horizontal plane 53 of the flow path 50 of the castable layer 5. The hot metal that has flowed to one end 23 flows down from one end 23 (tip surface 54) and flows down to a hot metal pan 64 or a torpedo car arranged at a position lower than the tilting gutter 1 (one end 23). Will be transferred.

When the other end 24 is tilted in the direction of arrow B2 so as to be lowered, the hot metal flows down from the other end 24. In this case, the operation is opposite to the case where one of the above ends 23 is tilted in the A1 direction.

In the tilting gutter 1 of the present embodiment, the portion of the hot water contact portion 3 that is exposed to the hot metal to be poured is formed by a brick main body portion 31 made of a standard brick having a low porosity. Therefore, it is possible to suppress physical damage (gouge or chipping) due to the collision of the hot metal falling on the brick body 31 of the hot water contact portion 3.

In the tilting gutter 1 of the present embodiment, the hot water contact portion 3 embedded in the castable layer 5 with the upper surface 30 exposed is provided with the brick main body portion 31 and the outer peripheral block portion 35. The porosities of the brick main body 31 (standard brick), the outer peripheral block 35 (precast block), and the castable layer 5 (castable) have a relationship of brick main body 31 <peripheral block 35 <castable layer 5. Further, it has a relationship of the brick main body 31 << castable layer 5.

Therefore, the amount of damage to the outer peripheral block portion 35 when the hot metal is received is an amount of damage between the brick main body portion 31 and the castable layer 5, and a gentle damage form is shown between the hot water contact portion 3 and the castable layer 5.

On the other hand, as shown in the partially enlarged cross-sectional view of FIG. 8, when the brick main body portion 31 and the castable layer 5 are formed in contact with each other (that is, the hot water contact portion 3 does not have the outer peripheral block portion 35 and is a hexahedron). Since the difference in porosity between the brick main body 31 and the castable layer 5 is large, the castable layer 5 is worn first. This wear increases as the hot metal flows, and as shown in FIG. 9, the side surface 34 of the brick body 31 of the hot water contact portion 3 is exposed. Then, the hot metal invades from the interface between the brick main body 31 and the castable layer 5, and infiltrates into the lower surface 33 side of the brick main body 31. When the hot metal invades the lower surface 33 side of the brick main body 31, a force acts on the brick main body 31 from the lower surface 33 toward the upper surface 32, the brick main body 31 rises from the castable layer 5, and the tilting gutter 1 is damaged.

As described above, the tilting gutter 1 of this embodiment has improved wear resistance to hot metal. As a result, the tilting gutter 1 (long-life tilting gutter) having more excellent durability is obtained.
In the tilting trough 1 of the present embodiment, the residual dimensional change rate of the brick main body 31 and the outer peripheral block 35 is 0.1% or more, and the absolute value of the difference between the residual dimensional change rate of the brick main body 31 and the outer peripheral block 35. Is 0.5% or less.
Specifically, as the material of the brick main body 31 of the hot water contact portion 3 of the tilting gutter 1 of this embodiment, the compounding example 10 in Table 1 having a residual dimensional change rate of 0.5% is used, and the outer peripheral block portion 35 When Formulation Example 16 in Table 2 having a residual expansion coefficient of 0.5% was used as the material, the amount of hot metal treated was 100% of the amount of hot metal treated in the conventional tilting gutter 1 shown in FIGS. 8 to 9. Occasionally, it is 150%, and the amount of hot metal processed is improved by 50%.

Since the residual dimensional change rate of the brick main body 31 and the outer peripheral block 35 of the hot water contact portion 3 is 0.1% or more, both the brick main body 31 and the outer peripheral block 35 are cooled after being exposed to a high temperature. Even if it does, it does not shrink more than before heating. Due to this residual thermal expansion, the occurrence of joint opening at the interface between the brick main body 31 and the outer peripheral block 35 is suppressed when the hot metal flows, and the infiltration (insertion) of the hot metal from the joint is suppressed. Further, at the interface between the hot water contact portion 3 and the castable layer 5, the generation of a gap is similarly suppressed.

Further, since the residual dimensional change rate of the brick main body 31 and the outer peripheral block 35 of the hot water contact portion 3 is 0.1% or more, the hot metal penetrates (inserts) from the joint even when the tilting gutter 1 is repeatedly used. ) Is suppressed. More specifically, the tilting gutter 1 may be allowed to cool and the overall temperature may drop between the time when the hot metal is poured and the time when the next hot metal is poured. In such a case, there is a possibility that a joint opening may occur between the cooled brick main body portion 31 and the outer peripheral block portion 35. Then, if the next hot metal is poured in the state where the joint opening exists, the hot metal may infiltrate from the joint. When the residual dimensional change rate of the brick main body portion 31 and the outer peripheral block portion 35 is 0.1% or more, the occurrence of joint opening during cooling is suppressed.

Further, since the absolute value of the difference in the residual dimensional change rate between the brick main body 31 and the outer peripheral block 35 is 0.5% or less, the difference in the residual dimensional change rate between the brick main body 31 and the outer peripheral block 35 is excessive. It does not become large, and damage to the hot water contact portion 3 is suppressed. If there is a difference in the residual dimensional change rate, there will be a difference in the expanded dimensions of both 31 and 35 after heating and cooling, and the joints will widen. As a result, the hot metal easily invades the joint, which leads to damage to the tilting gutter 1.

In the tilting gutter 1 of this embodiment, the residual dimensional change rate of the brick main body 31 is 0.1 to 1.0%, and the residual dimensional change rate of the outer peripheral block 35 is 0.1 to 1.0%. .. When the residual dimensional change rate of the brick main body portion 31 and the outer peripheral block portion 35 is within this range, it is possible to prevent the residual dimensional change rate of the hot water contact portion 3 from becoming excessively large.

In the tilting gutter 1 of this embodiment, the brick main body 31 has a frustum shape in which the upper surface 32 to which the hot metal hits is smaller than the lower surface 33, and the outer peripheral block portion 35 has a frame shape in which the brick main body 31 is fitted. According to this configuration, the brick main body 31 and the outer peripheral block 35 are in close contact with each other without causing joint opening, and damage (drilling or melting damage) due to hot metal falling on the brick main body 31 of the hot water contact portion 3 can be suppressed. Can be done.

In the tilting gutter 1 of the present embodiment, the outer peripheral block portion 35 faces the outer circumference in the radial direction of the upper surface 36 to which the hot metal hits, the lower surface 37 facing the upper surface 36, and the side surface connecting the upper surface 36 and the lower surface 37. It has a surface 40, and the outer peripheral surface 40 has a plurality of steps where a surface parallel to the upper surface 36 or the lower surface 37 of the frame shape and a surface along the axial direction of the frame shape intersect. According to this configuration, even if the hot metal invades from the upper surface 36 side along the outer peripheral surface 40 of the outer peripheral block portion 36, the hot metal flows along the outer peripheral surface 39. By having a plurality of step portions, the distance through which the hot metal flows becomes long, and it becomes difficult for the hot metal to flow into the lower surface of the hot water contact portion 3. As a result, the floating of the hot water contact portion 3 due to the hot metal is suppressed, and the damage of the tilting gutter 1 is suppressed.

1: Tilt gutter 2: Tilt gutter main body 20, 21 Tilt surface 22: Horizontal plane 23, 24: End 25: Hot metal discharge port 3: Hot water contact part 30: Top surface 31: Brick body part 32: Top surface 33: Bottom surface 34 : Side 35: Outer block 36: Upper surface 37: Lower surface 38: Inner peripheral surface 39, 40: Side surface 5: Castable layer 50: Flow path 51, 52: Inclined surface 53: Horizontal plane 54, 55: Tip surface 60: Blast furnace 61 : Large gutter 62: Middle gutter 63: Middle gutter tip exit 64: Hot metal pot

Claims (5)

A tiltable shallow-bottomed container-shaped tilting gutter body (2) and
A castable layer (5) made of a castable material formed on the inner surface of the main body of the tilting gutter, and
A hot water contact portion (3) embedded in the castable layer in a state where the upper surface (30) is exposed and receiving the molten metal to be poured on the upper surface.
It is a tilting gutter (1) with
The hot water contact portion (3) is made of any one of alumina-magnesia-carbon type, alumina-silicon carbide-magnesia-carbon type, and alumina-silicon carbide-godite-carbon type to which the hot metal is poured. Alumina-spinel-silicon carbide system, alumina-magnesia-silicon carbide that fits the brick body (31) and the hot metal flowing along its upper surface (36) and fitting the brick body inside. A tilting gutter characterized by having an outer peripheral block portion (35) made of a frame-shaped precast block made of a system material. The brick main body portion (31) and the outer peripheral block portion (35) have a residual dimensional change rate of 0.1% or more at 1400 ° C. × 5 hours under a reducing atmosphere.
The tilting gutter according to claim 1, wherein the absolute value of the difference between the residual dimensional change rate of the brick main body portion and the residual dimensional change rate of the outer peripheral block portion is 0.5% or less. The residual dimensional change rate of the brick body is 0.1 to 1.0%.
The tilting gutter according to claim 2, wherein the residual dimensional change rate of the outer peripheral block portion is 0.1 to 1.0%. The tilting gutter according to any one of claims 1 to 3, wherein the brick main body (31) has a frustum shape in which the upper surface (32) to which the hot metal hits is smaller than the lower surface (33). The outer peripheral block portion (35) has an upper surface (36), a lower surface (37), and an outer peripheral surface (39, 40).
The tilting gutter according to any one of claims 1 to 4, wherein the outer peripheral surface (40) has a plurality of step portions.

Images