JP2000119714A - Stave - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain the heat removing quantity to be stably small so that a heat insulating layer is not exposed to the outer part by forming the main body of a stave with copper or a copper alloy and arranging the heat insulating layer between a passage for coolant and the front surface at the inside of a furnace. SOLUTION: The main body 1 of the rectangular plate-like stave is formed with copper or a copper alloy. The heat insulating refractories 15 are set between the cooling water passage 3 in the inner part of the stave main body 1 and the front surface of the main body 1. This heat insulating refractory 15 is composed of a rectangular bar-like body having a fixed width and thickness, and a plurality of heat insulating refractories are set by vertically arranging in the width direction of the main body 1 apart with each fixed interval. Then, the heat insulating layer composed of the heat insulating refractories 15 and copper, etc., is formed in the width direction of the main body 1. The area ratio of the copper part (main heat conducting cross sectional area) in the heat insulating layer is desirably about 35-40%. The front surface at the inside of the furnace on the front surface copper part of the stave 1 is made flat at the contacting surface with packing materials in the furnace. The thickness of the front surface copper part of the stave main body 1 is made as thinner as possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a copper or copper alloy stave.

[0002]

2. Description of the Related Art A stave cooling method is known as a method of cooling a furnace body in a blast furnace. Conventional staves are generally made of cast iron.However, under the conditions of repeated heat fluctuations in the furnace, the material inside is cast iron. Progress, or warpage occurs due to thermal stress, thereby hindering the profile inside the furnace, or causing cracks in the stave itself, thus shortening the life of the furnace.

Therefore, a stave using copper or a copper alloy, which is superior in physical properties such as thermal conductivity and ductility, has recently been developed. By using copper or a copper alloy, the stave body has a uniform temperature distribution at a lower temperature, thereby suppressing the generated thermal stress and reducing the amount of deformation. Therefore, damage to the stave body is reduced, and the life of the furnace can be extended. However, when the material of the stave is changed from cast iron to copper, the effect of cooling the contents by the stave is increased due to the excellent thermal conductivity of copper. For this reason, depending on where the stave is attached, the amount of heat removal may be excessive, and the furnace charge may be cooled more than necessary, resulting in a problem that the fuel ratio increases.

[0004] In order to solve such a problem, for example, there is an invention of a cooling plate for a vertical furnace disclosed in Japanese Patent Publication No. 63-56283. FIG. 10 is a rear view of the stave disclosed in the publication, and FIG. 11 is a view taken along a line AA in FIG.
It is sectional drawing. In this specification, the back surface of the stave refers to a surface facing the outside of the furnace (steel shell) when the stave is installed in the furnace body, and the front surface refers to a surface facing the inside of the furnace.

The configuration of a conventional stave will be described with reference to FIGS. Reference numeral 50 denotes a rectangular plate-shaped stave made of copper or a copper alloy, in which a cooling water passage 53 is formed. Reference numeral 55 denotes an inlet / outlet pipe connected to the cooling water passage 53 and connected to a cooling water supply side (not shown). In addition, on the back of the stave, an unillustrated mounting bolt for fixing the stave body to the iron shell is provided. Reference numeral 57 denotes a plurality of horizontal grooves formed on the front surface of the stave.
7, a refractory material (not shown) is attached. Therefore, the stave front has a configuration in which copper and refractory material are alternately arranged.

In the above conventional stave,
By reducing the copper area on the front side of the stave, the amount of heat removed can be reduced.

[0007]

However, in the conventional stave as described above, since the refractory material is installed in a bare state inside the furnace, the stave is caused by contact abrasion or cracking with the filling in the furnace. The volume of the refractory material on the front surface decreases, the exposed copper area increases over time, and the amount of heat removed gradually increases. For this reason, even though the amount of heat removal can be suppressed to some extent at first, there is a problem that the amount of heat removal increases due to the volume reduction of the refractory material due to aging.

[0008] In order to suppress the above-mentioned aging, the refractory material to be installed on the front of the stave is as follows.
Since it is necessary to select a material that has thermal shock and is difficult to crack, it is not possible to simply select a material with low thermal conductivity, and it is necessary to adopt a limited and expensive refractory material. It is a fact. For this reason, the heat transfer rate from the cooling layer of the stave (the layer with the water channel) to the front surface increases not only due to aging but also in the initial stage, and there is a problem that the amount of heat removal becomes excessive.

For this reason, the life of the furnace can be extended by adopting a copper stave. However, depending on the adopted portion, the amount of heat removal can be reduced due to a change in the use condition due to the material and furthermore, the aging. However, there is a problem that the fuel ratio increases due to the increase in the fuel ratio. In addition, since the refractory material is exposed, there is also a problem in workability that it is necessary to consider that no external force acts on the refractory material during installation.

The present invention has been made in order to solve such a problem, and an object of the present invention is to provide a stave made of copper or a copper alloy and capable of stably reducing the amount of heat removal. .

[0011]

A stave according to the present invention is made of copper or a copper alloy, and is characterized in that a heat insulating layer is provided between a passage for a cooling medium and a front surface inside the furnace. .

Further, the heat insulating layer is characterized by having a structure filled with a heat insulating refractory.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 1 is a side view of Embodiment 1 of the present invention, FIG. 2 is a plan view, FIG. 3 is a rear view in FIG. 1, and FIG. 4 is a sectional view taken along the line AA in FIG. Hereinafter, the configuration of the first embodiment will be described with reference to FIGS. Reference numeral 1 denotes a main body of a rectangular plate-shaped stave, which is formed of copper or a copper alloy (hereinafter, referred to as “copper or the like”). Reference numeral 3 denotes a cooling water passage formed on the back side inside the main body 1, and reference numerals 5 to 11 denote inlet / outlet pipes through which cooling water connected to the cooling water passage 3 enters and exits. In addition, on the back of the stave, mounting bolts (not shown) for fixing the main body 1 to the steel shell are provided.

Reference numeral 15 denotes a heat-insulating refractory provided between the cooling water passage 3 inside the main body 1 and the front of the main body. As shown in FIGS. 2 and 4, the heat-insulating refractory 15 is formed of a rectangular rod having a certain width and thickness, and a plurality of the heat-insulating refractories are arranged vertically in the width direction of the main body 1 at certain intervals. . Therefore, as shown in FIG. 4, in the cross section where the heat insulating refractory 15 is installed, a heat insulating layer made of the heat insulating refractory 15 and copper or the like is formed in the width direction of the main body 1.

Here, the area ratio of copper or the like in the heat insulating layer will be described. From the viewpoint of suppressing the heat removal,
It is desirable to reduce the area ratio of copper etc.
If the area ratio of copper or the like is too small, the copper part on the front side of the stave (the part closer to the front side from the heat insulating layer in the main body 1) located in front of the heat insulating layer is overheated by the heat in the furnace, and the original shape cannot be maintained. It is feared that it will. Therefore, it is desirable to increase the area ratio of copper or the like from the viewpoint of protection of the copper portion of the stave front surface. Therefore, the present inventors have studied whether the area ratio of copper or the like should be reduced to suppress the heat removal and protect the copper portion on the front side of the stave. As a result, the copper portion in the heat insulating layer (the main heat passage section) It was found that the area ratio of is preferably about 35% to 40%.

Next, the shape and the like of the copper portion of the stave front surface of the stave will be described. The front side of the furnace inside the copper part of the stave front surface is made flat so that the contact surface with the furnace filling is flat to maintain the furnace inside profile. In addition, the thickness of the copper part of the stave front surface is made as thin as possible.

The thickness is made as small as possible so that the distance between the front side of the furnace and the cooling water passage 3 is made as short as possible, and the front side of the furnace is not overheated by exerting a cooling effect on the front side of the furnace. It is. Thus, by preventing the furnace front surface from overheating, the shape of the furnace front surface can be maintained and the furnace inside profile can be maintained.

In this embodiment constructed as described above, copper and the like formed inside the stave and the heat-insulating refractory material 1 are used.
The heat removal amount is suppressed by the heat insulating layer made of 5 restricting the heat passage, and the deterioration of the fuel ratio due to the excessive heat removal amount can be prevented. FIG. 5 is a graph illustrating the effect of the present embodiment, and shows a comparison of the heat transmittance at the front of the stave. In the drawing, graph B shows the heat transfer rate in the initial state of the conventional copper stave shown in FIGS. 10 to 12, and graph A shows the conventional stave in which the refractory material peeled off and the copper surface was fully exposed over time. , And the graph C shows the heat transmittance of the present embodiment. In each of the graphs, the heat transmittance in the initial state in the conventional example shown in the graph B is set to 1, and the others are shown as comparisons with this.

As can be seen from the graph, in the case of the conventional stave, the amount of heat removal has increased nearly twice (see graph A) due to aging, whereas in the present embodiment, Maintain the same amount of heat removal as in the initial stage (graph C
reference). Also, as for the heat removal amount in the initial state, the heat removal amount of the present embodiment is smaller than that of the conventional one (see graphs B and C). This is because this embodiment has a structure in which a heat insulating refractory material is provided inside the stave.
This is because the heat insulating material can be simply selected with priority given to the heat insulating property without much consideration of durability or the like.

As described above, in the stave according to the present embodiment, the copper or the like and the heat-insulating refractory 15 are provided between the copper portion in front of the stave in contact with the blast furnace filler and a layer having the cooling water channel 3 inside the stave. Since the heat insulating layer is formed, the thermal resistance on the front surface of the stave increases, and the amount of heat removal can be suppressed. Also,
Since the heat-insulating refractory 15 of the present embodiment has a structure that is confined inside the stave, the heat-insulating refractory 15 does not come into contact with the furnace filling, there is no volume loss due to wear or cracks, and a stable volume Maintenance becomes possible. For this reason, the heat removal amount can be stably suppressed without changing the heat removal amount due to aging as in the conventional example.

Furthermore, since the heat-insulating refractory 15 has a structure that is confined inside the stave, it is possible to simply select a refractory having low thermal conductivity without giving importance to durability, so that the heat removal performance is improved. It can be surely lowered. In addition, a relatively inexpensive insulated refractory can be selected, and the cost can be reduced. Furthermore, since the heat-insulating refractory 15 is inside the stave, handling during installation becomes very easy.

Embodiment 2 FIG. 6 is a side view of Embodiment 2 of the present invention, FIG. 7 is a plan view, FIG. 8 is a rear view in FIG. 1, and FIG. 9 is a sectional view taken along the line AA in FIG. In the figure, the same parts as those in the first embodiment are denoted by the same reference numerals. In the present embodiment, the heat insulating and refractory material 15 is arranged in the horizontal direction. With this arrangement, it is possible to prevent the heat-insulating refractory from falling off. Note that the area ratio of the copper portion is set to about 35% to 40% as in the first embodiment, and it is needless to say that the same effect as in the first embodiment can be obtained.

The heat-insulating refractories 15 and 20 in the first and second embodiments may be formed bricks inserted into a space formed in the main body 1 or may be made of an irregular-shaped refractory. Into a rod-shaped body. In addition, any heat insulating material can be used as long as the heat insulating refractories 15 and 20 can be inserted into the space without independently forming a rod-like body and can form a heat insulating layer.

[0024]

Since the present invention is configured as described above, it has the following effects.

A stave mainly made of copper or a copper alloy, in which a heat insulating layer is provided between the passage for the cooling medium and the front surface inside the furnace, so that the heat insulating layer is not exposed to the outside, and the furnace is filled. Since the destruction of the heat insulation layer due to contact with objects can be prevented,
The amount of heat removal can be stably suppressed. As a result, copper staves can be used without increasing the heat removal over time even in places where excessive heat removal from the furnace body is a concern.As a result, copper staves can be used throughout the furnace. It is possible to extend the life of the furnace significantly.

Further, since the heat insulating layer is configured to be filled with a heat insulating refractory, the refractory is confined in the stave. The heat removal performance can be reliably reduced. In addition, relatively inexpensive refractories can be selected, and costs can be reduced. In addition, the refractory is inside the stave, making handling during installation very easy.

[Brief description of the drawings]

FIG. 1 is a side view of a first embodiment of the present invention.

FIG. 2 is a plan view of the first embodiment of the present invention.

FIG. 3 is a rear view of the first embodiment of the present invention.

FIG. 4 is a sectional view taken along line AA in FIG.

FIG. 5 is a graph illustrating an effect of the first embodiment.

FIG. 6 is a side view of the second embodiment of the present invention.

FIG. 7 is a plan view of a second embodiment of the present invention.

FIG. 8 is a rear view of the second embodiment of the present invention.

9 is a sectional view taken along the line AA in FIG. 6;

FIG. 10 is a rear view of the conventional example.

11 is a sectional view taken along the line AA of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 3 Cooling channel 15 Insulated fireproof material

Claims (2)

[Claims] 1. A stave made of copper or a copper alloy, wherein a heat insulating layer is provided between a passage for a cooling medium and a front surface inside the furnace. 2. The stave according to claim 1, wherein the heat insulating layer is configured to be filled with a heat insulating refractory.