JPWO2011105346A1 - Stave and blast furnace - Google Patents

Abstract

The shaft stave is a stave provided on the inner periphery of the shaft portion of the blast furnace, and a stave body having a reference surface facing the internal space of the blast furnace; from the reference surface toward the inside of the blast furnace A plurality of protruding protrusions;

Description

  This application claims priority in 2010/02/23 based on Japanese Patent Application No. 2010-036841 for which it applied to Japan, and uses the content for it here.

  In existing blast furnaces, a structure is often used in which a stave is installed inside the iron skin and a refractory brick is installed inside. The inner surface of the blast furnace is subjected to mechanical wear by being exposed to the charge descending in the furnace while receiving high heat in the furnace. Then, after a certain period of time has passed and the refractory bricks are worn, the surface of the stave is worn. In order to cope with such wear, a structure has been developed in which a recess is formed on the surface of the stave inside the furnace, and a refractory is fitted in the recess (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2001-49316

  In the blast furnace, in the shaft part (from the middle part of the shaft to the upper part), the charge is layered granular coke and iron ore (sintered, lump ore, etc.), and the stave in this part is charged particles. Subjected to mechanical wear. With respect to such mechanical wear, the above-mentioned fitted refractory cannot be said to have sufficient durability.

  An object of the present invention is to provide a stave and a blast furnace capable of obtaining sufficient durability against mechanical wear caused by charged particles.

  The present invention is based on the knowledge obtained as a result of diligent research by the present inventors, that is, mechanical wear due to the particles of the charge depends on the shape and hardness of the charge particles and the descending speed. It is based on the knowledge that wear can be remarkably reduced by suppressing the speed of the charge on the surface of the steel (forming a stagnant layer). The present invention suppresses the speed of the charge on the surface of the stave based on the aforementioned knowledge. As a structure for forming the stagnant layer, protrusions were formed on the surface of the stave inside the blast furnace to make it easy to generate a stagnant layer of the charge covering the stave surface. The specific configuration is as follows.

The present invention employs the following means in order to solve the above problems and achieve the object.
That is,
(1) A stave according to an aspect of the present invention is a stave provided on the inner periphery of a shaft portion of a blast furnace, and a stave body having a reference surface facing the internal space of the blast furnace; A plurality of protrusions protruding toward the inside of the blast furnace.
According to the stave described in (1) above, the inner surface of the blast furnace is constituted by the reference surface of the stave body, and the charge descending in the furnace is decelerated by the protrusion protruding from the reference surface to the inside of the furnace. Thus, a stagnant layer is formed along the reference plane. The stagnant layer has a lower relative speed with respect to the reference surface of the stave body, reducing mechanical wear of the reference surface of the stave body due to the particles of the charge, resulting in a granular charge that descends the shaft part of the blast furnace. Also, sufficient durability can be obtained.

(2) In the stave described in (1) above, it is preferable that the protrusion dimension of the protrusion is 50 to 150 mm; and the interval between the adjacent protrusions is 200 to 700 mm.
According to the stave described in (2) above, since the protrusions (projection dimensions: 50 to 150 mm, intervals: 200 to 700 mm) are formed, the charge is decelerated, and in particular, part of the charge The movement is stopped by the protrusion, and a stagnant layer is formed.
As a result of the occurrence of such a stagnant layer, the plane is covered with the stagnant layer, so that the deceleration effect on the charge is enhanced.
In addition, in the present stave, in general, a general charge, that is, an ore-based charge having a particle size of about 8 to 25 mm and a coke-based charge having a particle size of about 20 to 55 mm are alternately charged. For objects, a stagnant layer is likely to be formed along the reference plane of the stave body. Thereby, the speed | rate of the charge particle | grains in the surface of a protrusion part front-end | tip can be suppressed, and the wear mitigation effect of the whole stave can be exhibited. If the distance is smaller than 200 mm, the recess formed by the adjacent protrusions along the reference surface of the stave body becomes ineffective, and the charge is not easily caught. On the other hand, if the interval is larger than 700 mm, the interval between the stagnant layers opens, and the covering effect does not sufficiently appear.

(3) As for the stave as described in said (1), it is desirable for the said projection part to be provided continuously or intermittently along the circumferential direction of the said blast furnace.
According to the stave described in the above (3), it is easy to properly maintain the circumferential balance in the furnace by the projections continuous in the entire circumference in the furnace circumferential direction, and to maintain a good operational record. Can do.
Moreover, the protrusion part may be arrange | positioned intermittently (intermittently) in the furnace circumferential direction. In this case, various geometric patterns such as a lattice shape and a zigzag shape can be adopted, but it is always preferable to adopt a point-symmetric arrangement considering the circumferential balance.

(4) As for the stave as described in said (1), it is desirable for the surface of the said projection part to be formed with a high-hardness material.
According to the stave described in (4) above, it is possible to prevent the protrusions themselves from being worn. In the stave of one aspect of the present invention, the reference surface of the stave body is reduced in wear by formation of a stagnant layer (cell flying) guided by the protrusion, but the protrusion itself is exposed from the stagnant layer to the inside of the furnace. In some cases, wear from particles of the undecelerated charge may continue to occur. In this case, by forming the surface of the protrusion with a high hardness material, wear of the protrusion can be suppressed, and a stagnant layer induced by the protrusion can be formed. Thereby, the wear reduction of the reference surface of the stave body by the stagnant layer can be stably maintained over a long period of time.

(5) The stave described in the above (4) has a recess formed in the stave body;
The protrusion is a block embedded in the recess and protruding from the reference surface;
The block is preferably made of a high hardness material.
According to the stave described in (5) above, the protrusion is provided in the recess formed in the stave body, that is, the stave body and the protrusion are separate, and therefore the material of the stave body is different. The protrusion of the high hardness material can be easily formed.
Alternatively, (6) in the stave described in the above (4), it is preferable that the protrusion is formed integrally with the stave body.
According to the stave described in (6) above, it is possible to easily implement the surface of the protruding portion made of the above-described high-hardness material, and because the protruding portion is formed integrally with the stave body, it is easy to manufacture. . In particular, when cooling pipes are also passed through the protrusions, it is very useful in processing that the protrusions and the stave body are integrated.

(7) As for the stave as described in said (1), it is desirable that the said stave main body is copper or a copper alloy.
According to the stave as described in said (7), the cooling efficiency as a stave used for a shaft part can be improved. Although the cooling performance of the copper or copper alloy stave is high, the stave layer according to one embodiment of the present invention can alleviate the wear of the stave body, although it is susceptible to wear due to charged particles. Furthermore, high cooling performance can be maintained over a long period of time.

(8) In the stave described in (1), it is preferable that a pipe line for cooling the protrusion is provided inside the protrusion.
According to the stave described in the above (8), in addition to the normal cooling conduit provided in the stave body, it can be directly cooled by the conduit that cools the protrusion, so the surface hardness of the protrusion can be reduced. It can be maintained high, and the anti-wear effect can be maintained over a long period of time.

(9) The stave described in the above (1) is an angle formed by a side surface on the lower side of the projecting portion and a reference surface among two opposing side surfaces of the projecting portion provided on both ends of the reference surface. Is preferably less than 90 degrees.
According to the stave described in (9) above, since the angle formed between the side surface on the lower side of the protrusion and the reference surface is less than 90 degrees, the charged object can be easily supported by the inclined protrusion. Thereby, since it can suppress further that a charging material falls below, sufficient durability is obtained also with respect to mechanical abrasion.

(10) A blast furnace according to an aspect of the present invention includes the stave according to any one of (1) to (9).
Here, it is desirable that the stave according to one aspect of the present invention be installed in a portion where the charged material falls in a granular state in the shaft portion of the blast furnace and its periphery.
In such a stave, even if there is a charge that falls in a granular form, a stagnant layer is formed by the protrusions of the stave, and wear on the reference surface of the stave body is reduced. In the shaft part of the blast furnace, wear due to the granular charge progresses, which makes it difficult to operate as a blast furnace, but by installing a wear-resistant stave in this part, the operation becomes It can be performed stably and the life as a blast furnace can be extended.

It is a mimetic diagram showing the blast furnace of a 1st embodiment of the present invention. It is sectional drawing which shows the stave of the said 1st Embodiment. It is a front view which shows the stave. It is a perspective sectional view showing the stave. It is a perspective sectional view showing the modification of the stave. It is a rear view which shows the stave. It is a schematic diagram which shows the effect | action of the said 1st Embodiment. It is a schematic diagram which shows the effect | action of the comparative example of the said 1st Embodiment. It is a schematic diagram which shows the effect | action of the comparative example of the said 1st Embodiment. It is a graph which shows the test result of the said 1st Embodiment. It is a graph which shows the test result of the said 1st Embodiment. It is sectional drawing which shows the stave of 2nd Embodiment of this invention. It is a front view which shows the stave. It is a rear view which shows the stave. It is sectional drawing which shows the stave of 3rd Embodiment of this invention. It is a front view which shows the stave. It is a rear view which shows the stave. It is sectional drawing which shows the stave of 4th Embodiment of this invention. It is a front view which shows the stave. It is a rear view which shows the stave.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
In FIG. 1, a blast furnace 1 has a cylindrical furnace body 2 constructed on a foundation ground.
The furnace body 2 has a cylindrical shape, and is sequentially divided into an upper gas collecting mantel 3 into a furnace mouth part S1, a shaft part S2, a furnace belly part S3, a morning glory part S4, a tuyere part S5, and a furnace bottom part S6. Generally, the inner diameter of the shaft portion S2 expands downward, the inner diameter of the furnace belly portion S3 is the maximum diameter, and the inner diameter of the morning glory portion S4 decreases downward.

In the furnace body 2, a charging device is usually installed in the gas collection mantel 3, and a granular charge 4 is charged into the blast furnace 1 from this charging device. As the charge 4, an ore-based charge having a particle size of about 8 to 25 mm and a coke-based charge having a particle size of about 20 to 55 mm are alternately charged. As a result, a massive band 4A in which iron ore and coke are alternately layered is formed in the furnace port portion S1 and the shaft portion S2 in the furnace.
The furnace body 2 is provided with a tuyere 5 above the furnace bottom S6, and hot air 5A is blown from here. The hot air 5A gradually raises the temperature of the coke in the block 4A as it descends in the furnace. A space with a high porosity in which the coke is fluidized is formed. Due to the high heat of the raceway 5B, the iron ore in the block 4A is melted.

The coke combustion and the melting of the iron ore proceed sequentially in the lower part of the massive band 4A, and a substantially conical fusion band 4B is formed in the blast furnace 1 from the morning glory part S4 to the lower part of the shaft part S2. .
The iron 6A melted in the fusion zone 4B passes through the dripping zone 4C, drops toward the furnace bottom S6, and accumulates in the furnace bottom S6 as a molten iron 6B. Coke or the like descends after passing through the dripping zone 4C, accumulates in the furnace bottom S6, and forms a conical furnace core 4D on the hot metal 6B.
In the furnace body 2, a hot iron outlet 6 is installed in the furnace bottom portion S <b> 6, and the hot metal 6 </ b> B accumulated in the furnace bottom portion S <b> 6 is taken out of the blast furnace 1 through the hot iron outlet 6.

The furnace body 2 has an iron skin 2A on the outermost periphery, and a cooling stave and a refractory brick 2D are affixed inside the iron skin 2A.
A stave 2B for the shaft is stretched in a region S7 facing from the upper portion of the shaft portion S2 to the middle lump 4A. In this region S7, since the granular charge 4 contained in the massive band 4A descends sequentially while contacting the surface of the stave 2B, mechanical wear may occur on the surface of the stave 2B.
The morning glory part and the furnace belly stave 2C are attached to the inner periphery of the region S8 including the furnace belly S3 and the morning glory part S4 from the lower part of the shaft part S2. In this region S8, since the high temperature charge 4 (cohesive zone root) included in the cohesive zone 4B descends sequentially while contacting the surface of the stave 2C, wear on the surface of the stave 2C is caused by high temperature. There is.
A heat-resistant brick 2D is stretched on the inner surface of the blast furnace 1 of these staves 2B and 2C as necessary. Further, the heat-resistant brick 2E is thickly stacked on the furnace bottom where hot molten iron is stored.

In this embodiment, the shaft stave 10 shown in FIG. 2 is adopted as the shaft stave 2B shown in FIG.
2, 3, 4 </ b> A, 4 </ b> B, and 5, the shaft stave 10 includes a stave body 11 having a reference surface R facing the internal space of the blast furnace 1, and a blast furnace 1 than the reference surface R. And a plurality of projecting portions 12 projecting inward. In the present embodiment, the protrusion 12 is formed integrally with the stave body 11. The stave body 11 is in the form of a thin plate cut out from a copper or copper alloy plate. The shaft stave 10 may be made of a cast or cast iron made of copper or a copper alloy.
As shown in FIG. 2 and FIG. 3, the protrusions 12 are formed in a plurality of rows on the surface side of the stave body 11 so as to be horizontally continuous. As shown in FIG. 2, a lower plane 13 is formed between the plurality of protrusions 12. One groove 21 is formed in the flat surface 13, and a refractory brick 15 is fitted into the groove 21.
Further, a refractory castable may be used in place of the refractory brick 15. Further, the number and location of the grooves 21 are not limited to this.

As shown in FIG. 4A, a plurality of protrusions 12 are provided horizontally and continuously on the surface side of the stave body 11. FIG. 4A is a diagram in which the groove 21 is omitted.
The flat surface 13 is formed by cutting from the surface of the stave body 11, and the protrusion 12 is formed by being left uncut during the cutting. Here, the flat surface 13 is the reference surface R of the shaft stave 10, and the protrusion 12 protrudes from the reference surface R of the shaft stave 10.

When the shaft stave 10 is affixed in the blast furnace 1, the protrusions 12 are continuously provided along the circumferential direction of the blast furnace 1 as shown in FIG. 4A. The part 12 forms a complete annular shape.
Moreover, the protrusion part 12 may be arrange | positioned intermittently (intermittently) along the circumferential direction in the blast furnace 1, as shown to FIG. 4B. In this case, various geometric patterns such as a lattice shape and a zigzag shape can be adopted, but it is always preferable to adopt a point-symmetric arrangement considering the circumferential balance. FIG. 4B is a view in which the groove 21 is omitted.

Furthermore, of the two side surfaces 12a and 12b of the protrusion 12 provided on both ends of the reference surface R, the angle θ between the lower surface of the protrusion 12, that is, the side surface 12a and the reference surface R is 90 degrees. Is less than. Specifically, when the blast furnace 1 is installed, the side surface 12a is horizontal with respect to the ground of the installation location.
As shown in FIG. 2, a bolt receiving portion 11 </ b> A for mounting on the blast furnace 1 is formed on the back side of the stave body 11.

As shown in FIG. 5, cooling pipe connection ports 16 </ b> A and 17 </ b> A are formed on the back side of the stave body 11, and cooling pipes 16 and 17 are formed inside the stave body 11. .
The pipe line 16 is disposed along the flat surface 13, and the flat surface 13 that is the reference surface R of the shaft stave 10 can be cooled by the cooling water supplied from the connection port 16 </ b> A.
Further, a pipe line 17 for cooling the protrusion 12 is provided inside the protrusion 12. With this configuration, the protrusion 12 can be cooled by the cooling water supplied from the connection port 17A.

It is preferable that the tip surface of the protrusion 12 is coated with a high hardness material such as TiN, TiC, WC, or Ti—Al—N.
As shown in FIG. 2, the protruding portion 12 of the shaft stave 10 has a protrusion amount (protrusion dimension) E from the reference surface R of 50 to 150 mm (approximately 50 mm of the maximum particle size of the coke-based charge having a large average particle size). 1 to 3 times), the thickness T in the height direction is 50 to 150 mm, and the distance D (corresponding to the height direction dimension of the flat surface 13) between other adjacent projections 12 is 200 to 700 mm, preferably 250-350 mm (50 mm before and after 300 mm).

The operation of the shaft stave 10 of this embodiment when the distance D between the adjacent protrusions 12 is 200 to 700 mm, more than 700 mm, and less than 200 mm will be described with reference to FIGS.
FIG. 6 schematically shows a state during operation of the shaft stave 10 of the present embodiment (projection amount E of the projecting portion: 50 to 150 mm, interval D: 200 to 700 mm). The enlarged shape of the shaft stave 10 of the present embodiment is schematically shown in the upper part of the paper surface of FIG. Further, in the lower part of the page of FIG. 6, graphs of the descending speeds V1 and V2 at the transverse position P1 and the transverse position P2 in the upper part of FIG. 6 are shown.
FIG. 7 shows a case where the distance D between the protrusions 12 is extremely large (the distance D between the protrusions 12> 700 mm). The enlarged shape of the shaft stave 10 is schematically shown in the upper part of the drawing of FIG. Further, in the lower part of the page of FIG. 7, graphs of the descending speeds V3 and V4 at the transverse position P3 and the transverse position P4 in the upper part of FIG. 7 are shown.
FIG. 8 shows a case where the distance D between the protrusions 12 is small (the distance D <200 mm between the protrusions). The enlarged shape of the shaft stave 10 is schematically shown in the upper part of the paper surface of FIG. Further, a graph of the lowering speed V5 at the transverse position P5 in the upper part of FIG.

  In each figure, the charge 4 descends inside the blast furnace 1 (see FIG. 1) during operation. The charge 4 in the blast furnace 1 descends at a substantially constant speed. In the vicinity of the surface of the shaft stave 10 (reference surface R), the charge 4 is decelerated due to friction with the shaft stave 10. As a result, a low speed region is generated between the stave 10 and the boundary B in the charge 4 near the shaft stave 10. As a result, the descending speed of the charge 4 is substantially constant (average descending speed V0) inside the furnace from the boundary B, but the descending speed gradually decreases from the boundary B to the reference plane R of the stave 10. The change in the descending speed at this time greatly differs depending on the shape of the reference surface R of the shaft stave 10, that is, the installation state of the protrusion 12.

As shown in FIG. 6, when the projection 12 (projection amount E: 50 to 150 mm, interval D: 200 to 700 mm) based on the present embodiment is formed, from the boundary B to the reference plane R of the shaft stave 10 In this region, the charge 4 decelerates, and in particular, a part of the charge 4 is stopped by the protrusion 12 to form the stagnant layers 19 and 18.
The stagnant layers 19 and 18 are formed on the upper surface side of the protruding portion 12 of the shaft stave 10 and grow upward along the flat surface 13 as a reference surface. Most of the movement of the stagnation layer 19 on the back side is stopped, and the stagnation layer 18 inside the blast furnace 1 is gradually replaced, and the descending speed of the stagnation layer 18 is very slow.
As a result of the stagnation layers 19 and 18 being formed, the flat surface 13 is covered with the stagnation layers 19 and 18, so that the deceleration effect on the charge 4 is enhanced.

  Looking at the descending speed V1 at the crossing position P1, the average descending speed V01 is substantially constant inside the blast furnace 1. The boundary B is a position at a distance B1 from the reference plane R of the shaft stave 10. The descending speed V1 decreases from the boundary B to the reference plane R, and becomes the descending speed VW1 on the reference plane R. The descending speed VW1 is very slow due to the formation of the stagnant layers 19 and 18, so that the wear of the shaft stave 10 on the stave body 11 is suppressed.

Looking at the descending speed V2 at the crossing position P2, the average descending speed V02 inside the blast furnace 1 is the same as the average descending speed V01 at the transverse position P1, and the descending speed is from the boundary B to the reference plane R of the shaft stave 10. Decrease. At this time, the descending speed V2 and the descending speed V1 are the same. The tip surface R1 of the protrusion 12 has a descending speed VL2. Here, the distance from the reference surface R to the tip surface R1 corresponds to the protrusion dimension E of the protrusion 12.
The descending speed VL2 is the same as the descending speed VL1 at the position corresponding to the front end surface R1 at the crossing position P1. At the crossing position P1, the descending speed VL1 at the tip end surface R1 has a large internal friction between the charge 4 of the stagnant layers 19 and 18 formed by the protrusion 12 and the boundary portion of the charge 4 that descends. The descent speed becomes slower. The descending speed VL2 is affected by the descending speed VL1, and becomes the same descending speed as the descending speed VL1.

As shown in FIG. 7, when the distance D between the protrusions 12 of the shaft stave 10 is very large (protrusion distance D> 700 mm), the boundary B is a position at a distance B3 from the reference plane R of the shaft stave 10. There is a deceleration of the charge 4 in the region from the boundary B to the reference plane R. However, the stagnant layers 19 and 18 formed by the protrusion 12 as shown in FIG. 6 are not formed over the entire range of the height W of the recess, but are formed only at the lower end portion of the height W.
Looking at the descending speed V3 at the crossing position P3, the average descending speed V03 inside the blast furnace 1 is the same as the average descending speed V01 at the transverse position P1, and the descending speed is from the boundary B to the reference plane R of the shaft stave 10. Decrease. At this time, the descending speed decreases like the descending speed V1, but since the distance D between the protrusions 12 is extremely large, the influence of the stagnant layers 19 and 18 on the plane 13 is small, and the descending speed of the plane 13 is the same as that of the plane 13. It becomes the frictional force of the container 4. As a result, when the distance D between the protrusions 12 of the shaft stave 10 is very large, the descending speed is not significantly reduced.

Looking at the descending speed V4 at the crossing position P4, the average descending speed V04 inside the blast furnace 1 is the same as the average descending speed V03 at the transverse position P3, and the descending speed is from the boundary B to the reference plane R of the shaft stave 10. Decrease. At this time, the lowering speed decreases like the lowering speed V3, but at the tip end surface R1 of the protrusion 12, the lowering speed VL4 is reached. Here, the distance from the reference surface R to the tip surface R1 corresponds to the protrusion dimension E of the protrusion 12.
The descending speed VL4 is faster than the descending speed VL3 at the distal end surface R1 at the relative position at the transverse position P3. The cross section at the crossing position P4 is smaller in the cross section from the boundary B of the crossing position P3 to the reference plane R and the cross section from the boundary B to the front end face R1 of the crossing position P4. That is, since the distance from the boundary B of the crossing position P4 to the tip surface R1 is shorter than the distance from the boundary B of the crossing position P3 to the reference plane R, when the same charge 4 passes, the descending speed VL3 Compared to the lowering speed VL4, the lowering speed becomes faster.

In the reference surface R of the shaft stave 10, the lowering speed VW3 at the reference surface R is significantly higher than the lowering speed VW1, and the wear on the flat surface 13 which is the reference surface of the stave body is significantly increased compared to the state of FIG. .
As described above, when the distance D between the protrusions 12 of the stave 10 is very large, the stagnant layers 19 and 18 are formed only at the lower end portion of the height W of the recess, so that the stagnant layers 19 and 18 are formed. In the absence portion (the upper end portion of the height W), the wear on the flat surface 13 which is the reference surface R of the stave body 11 is greatly increased.

  As shown in FIG. 8, when the distance D between the protrusions 12 is small (distance D <200 mm between the protrusions), the boundary B is a position at a distance B5 from the reference plane R of the shaft stave 10, and from the boundary B to the stave In the region up to the reference plane R of the main body, the speed of the charge 4 is reduced. However, since a flat surface is formed at the tip end surface R1 of the protrusion 12, the friction force between the charge 4 and the flat surface is generated, and the deceleration effect described with reference to FIG. 6 cannot be obtained.

  Looking at the descending speed V5 at the crossing position P5, it is the average descending speed V05 inside the blast furnace 1, and the descending speed V5 decreases from the boundary B to the reference surface R of the stave body 11, but at the tip end surface R1 of the protrusion 12. The descent speed VL5. From the tip surface R1 to the reference surface R of the stave body, the descent speed is almost zero because of the stagnant layer 19, but since a flat surface is formed at the tip surface R1, there is a difference between the charge 4 and the flat surface. As a result, the lowering speed VL5 becomes faster than the lowering speed VL2.

  Thus, in the shape of FIG. 8, a flat surface is formed on the tip end surface R1 of the protrusion 12, and the deceleration effect as described in FIG. 6 cannot be obtained. The descending speed VL5 with respect to the tip of the protrusion 12 is higher than the descending speed VL2 in FIG.

As described above, in the shaft stave 10 of the present embodiment, the descending speed of the charge 4 that contacts the shaft stave 10 varies depending on the arrangement of the protrusions 12, that is, the interval between the adjacent protrusions 12.
Here, an appropriate range of the interval D of the protrusions 12 will be described based on a test result of a tenth model of the shaft stave 10 of the present embodiment.
FIG. 9 shows that the distance D between the protrusions 12 of the shaft stave 10 is changed from 0 to 120 mm in the configuration shown in FIG. It is the graph which measured the speed | rate of the charge 4 which contacts the plane 13 surface which is a reference plane of a stave main body.
FIG. 10 is a graph obtained by measuring the descending speed VL (that is, the speed of the charge 4 contacting the tip of the protrusion 12) at the tip surface R1 in the configuration of FIG. 6 described above. The thickness T of the protruding portion 12 of the shaft stave 10 was 5 mm, and the protrusion amount E was measured for 5 mm and 10 mm. The horizontal dotted line in the figure is the average descending speed V01 in the blast furnace 1, and was 2.4 mm / sec in this test.

In FIG. 9, the descending speed VW at the reference surface R of the main body of the shaft stave 10 is lower than the average descending speed V0 in all the measured settings, and in particular, when the interval D between the protrusions 12 is 100 mm or less, the descending speed VW. It can be seen that there is a significant decrease. Further, when the protrusion amount E is 15 mm, the lowering speed VW decreases as in the case where the protrusion amount E is 10 mm.
In FIG. 10, the descending speed VL at the tip end surface R1 of the projecting portion 12 of the shaft stave 10 is less than the average descending speed V01 when the interval D of the projecting portion 12 is 80 mm or less, and the interval D is in the range of 20 to 70 mm. In particular, the distance D between the protrusions 12 at the minimum speed of the descending speed VL is 30 mm, and the smallest value is 25 to 35 mm which is 5 mm before and after this 30 mm. Further, when the protrusion amount E is 15 mm, the descent speed VL is the same as when the protrusion amount E is 5 mm and 10 mm.
That is, even when the protrusion amount E is 15 mm, an appropriate deposit layer can be formed inside the blast furnace 1. Therefore, if the protrusion E is 10 mm or more and 15 mm or less, the self-running effect can be obtained, the adhering matter can be properly maintained, the heat load is low, the fuel is low, and the stable operation is achieved. Cheap. As a result, the life of the blast furnace 1 can be significantly extended.
From the above, when the test results of a tenth model are converted into an actual furnace, when the protrusions 12 of the shaft stave 10 are arranged, the interval D between the protrusions 12 is in the range of 200 to 700 mm, more preferably. It can be said that it is desirable to be in the range of 250 to 350 mm.

According to the present embodiment described above, the following effects can be obtained.
In the shaft stave 10, the in-furnace surface of the blast furnace 1 is configured with the flat surface 13 of the stave body 11 as the reference plane R. Therefore, the charge 4 descending in the blast furnace 1 is decelerated and along the reference plane R. As a result, stagnant layers 19 and 18 are formed. Thereby, the relative speed of the stagnant layers 19 and 18 with respect to the reference surface R is reduced, and the mechanical wear of the reference surface R due to the particles of the charge 4 is reduced in the stave body 11. Therefore, by disposing the stave of the present embodiment on the shaft portion S2, which is a portion exposed to the granular charge descending in the blast furnace 1, the granular material descending as a massive band 4A from the upper portion to the middle portion of the shaft portion S2. Sufficient durability can be obtained with respect to the charged material.

  By setting the distance D between the protrusions 12 to 200 to 700 mm, the current general charge 4, that is, an ore charge having a particle size of about 8 to 25 mm and about 20 to 55 mm, which are alternately charged, The stagnant layers 19 and 18 are likely to be formed along the reference plane R with respect to a coke-type charge having a particle size of. As a result, the lowering speed VW at the reference surface R can be reduced, and the lowering speed VL of the particles of the charge 4 at the tip of the protrusion 12 can be suppressed. It can be.

Since the protrusion 12 has a surface coated with a high hardness material, the protrusion 12 itself can be prevented from being worn. Therefore, the stagnation layers 19 and 18 induced by the protrusion 12 and the effect of reducing the wear of the reference surface R can be stably maintained over a long period of time.
Since the protruding portion 12 is formed integrally with the stave body 11, the manufacturing is easy, and the processing for passing the cooling conduit 17 through the protruding portion 12 can be simplified.

Further, in the shaft stave 10 of the present embodiment, the stave body 11 is made of copper or a copper alloy, but may not necessarily be copper or a copper alloy. The stave body 11 is preferably made of copper or a copper alloy because the cooling efficiency of the shaft stave 10 can be increased. By using a stave made of copper or copper alloy, the cooling performance is high, but it is easy to be worn by the particles of the charge 4, but in this embodiment, the stagnant layers 19 and 18 can alleviate the wear. Thereby, high cooling performance can be maintained over a long period of time.
Since the pipe body 16 is provided in the stave body 11 and the pipe line 17 is also provided in the protrusion 17, the surface of the protrusion 12 can be maintained at a high hardness by cooling the protrusion 12, and the effect of preventing wear is prolonged. Can be maintained over a period of time.

In this embodiment, the blast furnace 1 can improve wear resistance by using the shaft stave 10 based on this embodiment as the shaft stave 2B.
In particular, the shaft stave 10 according to the present invention is installed as the stave 2B in the region S7 of the shaft portion S2 of the blast furnace 1 where the charge 4 descends as a lump 4A in a granular state. Even if there is the entrance 4, the stagnant layers 19 and 18 are formed by the protrusion 12 of the shaft stave 10, and wear from the reference surface R is reduced.

In the shaft portion S <b> 2, wear due to the granular charge 4 progresses, which causes a difficulty in operation as the blast furnace 1. However, in this embodiment, since the wear-resistant shaft stave 10 is installed in this portion, the operation of the blast furnace 1 can be stably performed for a long time, and the life as a blast furnace can be extended.
In the blast furnace 1, since the protruding portions 12 of the shaft stave 10 disposed in the blast furnace 1 are continuous over the entire circumference in the furnace circumferential direction, it is easy to properly maintain the circumferential balance in the blast furnace 1, The operation of the blast furnace 1 can be maintained well.

[Second Embodiment]
11, 12 and 13 show a second embodiment of the present invention.
The shaft stave 20 of the present embodiment is used as a shaft stave 2B in the blast furnace 1 of the first embodiment described above. The structure of the blast furnace 1 is the same as that of the first embodiment described above, and the shaft stave 20 of this embodiment is the same as the shaft stave 10 of the first embodiment described above. Accordingly, the description of the common parts with the stave 10 of the first embodiment described above will be omitted, and different parts will be described below.

  11, 12, and 13, a shaft stave 20 includes a stave body 11, a bolt receiving portion 11 </ b> A, a protruding portion 12, a flat surface 13, a refractory brick 15, similar to the shaft stave 10 of the first embodiment described above. It has a pipe line 16 and a connection port 16A. However, the pipe line 17 and the connection port 17A formed inside the protrusion 12 in the shaft stave 10 of the first embodiment are omitted.

In this embodiment, the same effect as that of the first embodiment described above can be obtained. However, since there is no pipe line 17 formed inside the protrusion 12, local cooling of the protrusion 12 cannot be obtained.
In this respect, local cooling with respect to the protrusion 12 of the shaft stave 10 of the first embodiment described above can be obtained. Thereby, since durability of the projection part 12 can be maintained high, it is most suitable for a part of high load in thermal or wear in the blast furnace 1. On the other hand, the shaft stave 20 according to the present embodiment has a simple structure and can be manufactured at a reduced cost because the pipe 17 is not provided. It can be said that 20 is preferable.

[Third Embodiment]
FIGS. 14, 15 and 16 show a third embodiment of the present invention.
The shaft stave 30 of the present embodiment is used as the shaft stave 2B in the blast furnace 1 of the first embodiment described above. The structure of the blast furnace 1 is the same as that of the first embodiment, and the stave 30 of the present embodiment is the same in basic structure as the shaft stave 10 of the first embodiment. Accordingly, the description of the common parts with the shaft stave 10 of the first embodiment will be omitted, and different parts will be described below.

  14, 15, and 16, the shaft stave 30 includes a stave body 11, a bolt receiving portion 11 </ b> A, a flat surface 13, a refractory brick 15, a pipe line 16, and a connection similar to the shaft stave 10 of the first embodiment. It has a mouth 16A. However, in the shaft stave 30 of the present embodiment, the protruding portion 12 is not integral with the stave body 11 as in the shaft stave 10 of the first embodiment, and inside the protruding portion 12 of the first embodiment. It is different from the pipe line 17 and the connection port 17A. That is, a protrusion 32 and a pipe 37 inside thereof are provided separately from the stave body 11.

The protrusion 32 of the shaft stave 30 is a square bar-like block formed of a high-hardness material such as TiN, TiC, WC, or Ti—Al—N. A block may be formed of copper, a copper alloy, or other material, and the surface thereof may be coated with a high hardness material such as TiN, TiC, WC, or Ti—Al—N.
A groove (concave portion) 32A is formed in the flat surface 13 serving as the reference surface R of the stave body 11, and the protrusion 32 described above is fitted into the groove 32A. With this configuration, the protrusion 32 protrudes from the reference surface R.

A pipe line 37 is passed through some of the protrusions 32. As shown in FIG. 16, the protrusion 32 formed with the pipe 37 is fixed by a bolt 32 </ b> C screwed from the back side of the stave body 11 (outside the blast furnace 1), as shown in FIG. 16. Further, both ends of the pipe line 37 are fixed by the connection ports 37A of the pipe line screwed in the same manner.
As shown in FIGS. 14 and 15, bolts 32 </ b> B are screwed into the other protrusions 32 from the inside of the blast furnace 1, thereby fixing the protrusions 32.
In addition, in the state fitted in the stave main body 11, the space | interval D of the projection part 32, the protrusion amount E, and thickness T are the same as that of 1st Embodiment mentioned above.

In this embodiment, the same effect as that of the first embodiment described above can be obtained.
Furthermore, in the present embodiment, since the protrusion 32 of the shaft stave 30 and the stave body 11 are separate, the protrusion 32 of a high hardness material different from the material of the stave body 11 can be easily formed. Further, the wear resistance of the protrusion 32 can be further enhanced.

[Fourth Embodiment]
17, FIG. 18, and FIG. 19 show a fourth embodiment of the present invention.
The shaft stave 40 of this embodiment is used as the shaft stave 2B in the blast furnace 1 of the first embodiment described above. The structure of the blast furnace 1 is the same as that of the first embodiment, and the basic structure of the shaft stave 40 of this embodiment is the same as that of the shaft stave 10 of the first embodiment. Accordingly, the description of the common parts with the shaft stave 10 of the first embodiment will be omitted, and different parts will be described below.

  17, 18 and 19, the shaft stave 40 includes a stave body 11, a bolt receiving portion 11 </ b> A, a flat surface 13, a refractory brick 15, a pipe line 16 and a connection similar to the shaft stave 10 of the first embodiment. It has a mouth 16A. However, instead of the protruding portion 12 integral with the stave body 11 in the shaft stave 10 of the first embodiment, a protruding portion 32 separate from the stave body 11 similar to the third embodiment described above is provided. . Here, in this embodiment, there is no pipe line 37 and connection port 37A inside the protrusion 32, and all the protrusions 32 are fixed by bolts 32C screwed from the back side of the stave body 11.

In this embodiment, the same effect as that of the third embodiment described above can be obtained. However, since there is no pipe line 37 formed inside the protruding portion 32 of the shaft stave 40, local cooling of the protruding portion 32 cannot be obtained.
In this respect, local cooling with respect to the projecting portion 32 of the shaft stave 30 of the third embodiment described above can be obtained. As a result, the durability of the protrusions 32 can be maintained high, so that the protrusions 32 are optimal for high load sites in the blast furnace 1 due to thermal or wear. On the other hand, the shaft stave 40 of the present embodiment has a simple structure and can be manufactured at a reduced cost because of the absence of the pipe line 37. It can be said that 40 is preferable.

[Modification]
In addition, this invention is not limited to embodiment mentioned above, The deformation | transformation etc. in the range which can achieve the objective of this invention are included.
In the embodiment, when the staves 10 to 40 are arranged in the blast furnace 1, the protrusions 12 and 32 of the shaft staves 10 to 40 are continuously annular in the furnace circumferential direction in the blast furnace 1. However, it may be an annular shape that is discontinuous with each other, may be zigzag arranged at different heights, may be arranged in a spiral shape with the height changing sequentially, and the like. However, circumferential balance is important for the operation of the blast furnace 1, and consideration should be given so that symmetry is obtained with respect to the center of the blast furnace 1.

In the above embodiment, the surface of the protruding portion 12 of the shaft stave 10 to 40 is coated with a high hardness material, or the protruding portion 32 itself is formed of the high hardness material. However, the use of the high hardness material is not essential. . However, since the shaft staves 10 to 40 protrude from the reference surface R of the stave body 11 and are susceptible to wear by the charge 4, it is desirable to ensure wear resistance by a high hardness material.
In addition, the arrangement of the projections 12, the cross-sectional shape, the arrangement of the pipes 16 and 17, the overall shape and dimensions of the shaft staves 10 to 40 may be appropriately selected in the implementation.

DESCRIPTION OF SYMBOLS 1 ... Blast furnace 2 ... Furnace body 2A ... Iron skin 2B, 2C ... Stave 2D, 2E ... Heat-resistant brick 3 ... Gas collection mantel 4 ... Charge 4A ... Lump 4B ... Fusion zone 4C ... Dripping zone 4D ... Core 5 ... tuyere 5A ... hot air 5B ... raceway 6 ... tapping outlet 6A ... iron 6B ... hot metal 10-40 ... stave for shaft 11 ... stave body 11A ... bolt receiving part 12, 32 ... projection 13 ... plane 15 ... fire resistance Brick 16, 17, 37 ... Cooling pipelines 16A, 17A, 37A ... Connection port 19, 18 ... Stagnation layer 32A ... Groove 32B, 32C ... Bolt B ... Boundary D ... Spacing E ... Projection amount R ... Reference plane R1 ... Front end surface S1 ... Furnace port part S2 ... Shaft part S3 ... Furnace belly part S4 ... Morning glory part S6 ... Furnace bottom part S7 ... Installation area of shaft stave S8 ... Installation area of morning glory stave V01-V05 ... Average descending speed V ～V5 ... lowering speed of the falling rate VW～VW3 ... reference surface at a lowering speed VL～VL5 ... projecting tip

[0002]
It is based on the knowledge that the wear can be significantly reduced by suppressing the speed of the charge on the surface of the stave (forming a stagnant layer). The present invention suppresses the speed of the charge on the surface of the stave based on the aforementioned knowledge. As a structure for forming the stagnant layer, protrusions were formed on the surface of the stave inside the blast furnace to make it easy to generate a stagnant layer of charge covering the surface of the stave. The specific configuration is as follows.
[0007]
The present invention employs the following means in order to solve the above problems and achieve the object.
That is,
(1) A stave according to an aspect of the present invention is a stave provided on the inner periphery of a shaft portion of a blast furnace, and a stave body having a reference surface facing the internal space of the blast furnace; A plurality of protrusions protruding toward the inside of the blast furnace, and a groove recessed toward the outside of the blast furnace is formed on the reference surface between the plurality of protrusions of the stave body, Only the groove is provided with a refractory.
According to the stave described in (1) above, the inner surface of the blast furnace is constituted by the reference surface of the stave body, and the charge descending in the furnace is decelerated by the protrusion protruding from the reference surface to the inside of the furnace. Thus, a stagnant layer is formed along the reference plane. The stagnant layer has a lower relative speed with respect to the reference surface of the stave body, reducing mechanical wear of the reference surface of the stave body due to the particles of the charge, resulting in a granular charge that descends the shaft part of the blast furnace. Also, sufficient durability can be obtained.
[0008]
(2) In the stave described in (1) above, it is preferable that the protrusion dimension of the protrusion is 50 to 150 mm; and the interval between the adjacent protrusions is 200 to 700 mm.
According to the stave described in (2) above, since the protrusions (projection dimensions: 50 to 150 mm, intervals: 200 to 700 mm) are formed, the charge is decelerated, and in particular, part of the charge The movement is stopped by the protrusion, and a stagnant layer is formed.
As a result of the occurrence of such a stagnant layer, the plane is covered with the stagnant layer, so that the deceleration effect on the charge is enhanced.

The present invention employs the following means in order to solve the above problems and achieve the object.
That is,
(1) A stave according to an aspect of the present invention is a stave provided on the inner periphery of a shaft portion of a blast furnace, and a stave body having a reference surface facing the internal space of the blast furnace; A plurality of protrusions protruding toward the inside of the blast furnace, and a groove recessed toward the outside of the blast furnace is formed on the reference surface between the plurality of protrusions of the stave body, A refractory is provided only in the groove, and the stave body is made of copper or a copper alloy .
According to the stave described in (1) above, the inner surface of the blast furnace is constituted by the reference surface of the stave body, and the charge descending in the furnace is decelerated by the protrusion protruding from the reference surface to the inside of the furnace. Thus, a stagnant layer is formed along the reference plane. The stagnant layer has a lower relative speed with respect to the reference surface of the stave body, reducing mechanical wear of the reference surface of the stave body due to the particles of the charge, resulting in a granular charge that descends the shaft part of the blast furnace. Also, sufficient durability can be obtained.
Moreover, according to the stave as described in said (1), the cooling efficiency as a stave used for a shaft part can be improved. Although the cooling performance of the copper or copper alloy stave is high, the stave layer according to one embodiment of the present invention can alleviate the wear of the stave body, although it is susceptible to wear due to charged particles. Furthermore, high cooling performance can be maintained over a long period of time.

(3) As for the stave as described in said (1) or (2) , it is desirable for the said projection part to be provided continuously or intermittently along the circumferential direction of the said blast furnace.
According to the stave described in the above (3), it is easy to properly maintain the circumferential balance in the furnace by the projections continuous in the entire circumference in the furnace circumferential direction, and to maintain a good operational record. Can do.
Moreover, the protrusion part may be arrange | positioned intermittently (intermittently) in the furnace circumferential direction. In this case, various geometric patterns such as a lattice shape and a zigzag shape can be adopted, but it is always preferable to adopt a point-symmetric arrangement considering the circumferential balance.

(4) As for the stave as described in any one of said (1) -(3), it is desirable for the surface of the said projection part to be formed with high hardness material.
According to the stave described in (4) above, it is possible to prevent the protrusions themselves from being worn. In the stave of one aspect of the present invention, the reference surface of the stave body is reduced in wear by formation of a stagnant layer (cell flying) guided by the protrusion, but the protrusion itself is exposed from the stagnant layer to the inside of the furnace. In some cases, wear from particles of the undecelerated charge may continue to occur. In this case, by forming the surface of the protrusion with a high hardness material, wear of the protrusion can be suppressed, and a stagnant layer induced by the protrusion can be formed. Thereby, the wear reduction of the reference surface of the stave body by the stagnant layer can be stably maintained over a long period of time.

(5) The stave according to any one of (1) to (4), wherein a concave portion is formed in the stave body;
The protrusion is a block embedded in the recess and protruding from the reference surface;
The block is preferably made of a high hardness material.
According to the stave described in (5) above, the protrusion is provided in the recess formed in the stave body, that is, the stave body and the protrusion are separate, and therefore the material of the stave body is different. The protrusion of the high hardness material can be easily formed.
Alternatively, (6) in the stave according to any one of (1) to (4) , it is preferable that the protruding portion is formed integrally with the stave body.
According to the stave described in (6) above, it is possible to easily implement the surface of the protruding portion made of the above-described high-hardness material, and because the protruding portion is formed integrally with the stave body, it is easy to manufacture. . In particular, when cooling pipes are also passed through the protrusions, it is very useful in processing that the protrusions and the stave body are integrated.

( 7 ) In the stave according to any one of (1) to (6), it is preferable that a pipe line for cooling the protrusion is provided inside the protrusion.
According to the stave described in the above (8), in addition to the normal cooling conduit provided in the stave body, it can be directly cooled by the conduit that cools the protrusion, so the surface hardness of the protrusion can be reduced. It can be maintained high, and the anti-wear effect can be maintained over a long period of time.

( 8 ) The stave according to any one of the above (1) to (7) is formed by a side surface on the lower side of the protruding portion and a reference surface among two facing side surfaces of the adjacent protruding portion. The angle is preferably less than 90 degrees.
According to the stave described in (9) above, since the angle formed between the side surface on the lower side of the protrusion and the reference surface is less than 90 degrees, the charged object can be easily supported by the inclined protrusion. Thereby, since it can suppress further that a charging material falls below, sufficient durability is obtained also with respect to mechanical abrasion.

( 9 ) A blast furnace according to an aspect of the present invention includes the stave according to any one of (1) to (9 8 ).
Here, it is desirable that the stave according to one aspect of the present invention be installed in a portion where the charged material falls in a granular state in the shaft portion of the blast furnace and its periphery.
In such a stave, even if there is a charge that falls in a granular form, a stagnant layer is formed by the protrusions of the stave, and wear on the reference surface of the stave body is reduced. In the shaft part of the blast furnace, wear due to the granular charge progresses, which makes it difficult to operate as a blast furnace, but by installing a wear-resistant stave in this part, the operation becomes It can be performed stably and the life as a blast furnace can be extended.

Claims (10)

A stave provided on the inner periphery of the shaft portion of the blast furnace,
A stave body having a reference surface facing the internal space of the blast furnace;
A plurality of protrusions protruding toward the inside of the blast furnace from the reference surface;
Stave characterized by comprising. The protrusion dimension of the protrusion is 50 to 150 mm;
An interval between adjacent protrusions is 200 to 700 mm;
The stave according to claim 1, wherein:   The stave according to claim 1, wherein the protrusion is provided continuously or intermittently along the circumferential direction of the blast furnace.   The stave according to claim 1, wherein a surface of the protruding portion is formed of a high hardness material. A recess is formed in the stave body;
The protrusion is a block embedded in the recess and protruding from the reference surface;
The block is formed of a high hardness material;
The stave according to claim 4 characterized by things.   The stave according to claim 4, wherein the protrusion is formed integrally with the stave body.   The stave according to claim 1, wherein the stave body is made of copper or a copper alloy.   The stave according to claim 1, wherein a pipe line for cooling the protrusion is provided inside the protrusion.   The angle formed between the side surface on the lower side of the protrusion and the reference surface among the two opposing side surfaces of the protrusion provided on both ends of the reference surface is less than 90 degrees. Item 1. The stave according to item 1.   A blast furnace comprising the stave according to any one of claims 1 to 9.

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