JP3633519B2 - Stave cooler for metallurgical furnace and its mounting method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a stave cooler for a metallurgical furnace for cooling and protecting a furnace body of a metallurgical furnace such as a blast furnace and a method for mounting the same.
[0002]
[Prior art]
As is well known, the blast furnace is equipped with a high shaft and a bottom of the furnace, and ore and coke are charged from the top of the furnace and hot air is blown into the furnace from the tuyere at the pool. It is a metallurgical furnace that burns coke to reduce ore ore and is widely used as the most efficient pig iron production equipment. At present, the furnace body of blast furnaces in Japan is so-called that the core of the blast furnace is supported by several pillars and the load at the top of the furnace is supported by a steel frame as the size of the blast furnace increases. A steel-frame type is used. This iron skin is mainly made of welded structural steel (SM material), and is constructed by welding a large number of small pieces having a plate thickness of about 60 to 120 mm. On the inner surface side of the iron skin, heat-resistant bricks are stacked and arranged in order to reduce the heat load.
[0003]
Thus, the side wall of the furnace body composed of the iron shell and a large number of heat-resistant bricks is from the viewpoint of extending the life of the side wall brick and protecting the iron skin. (1) About 30 to 50 steps in the height direction of the furnace. Cooling plate method in which cooling plates of 36 to 52 steps are arranged in a staggered manner, (2) Sprinkling cooling method to sprinkle the furnace body, (3) Jacket cooling method using a cooling water flow path arranged around the furnace body, Furthermore, it is cooled by the stave cooler system etc. which arrange | position many stave coolers which have a cooling water flow path in (4) inside between an iron skin and a heat-resistant brick.
[0004]
Of these cooling methods, the stave cooler used in the stave cooler method generally has an early life due to wear and wear due to heat load caused by a direct high-heat atmosphere, and damage to the cooling pipe due to thermal expansion and warping of the main body. Many inventions for improving the durability of the stave cooler have been disclosed so far.
[0005]
FIG. 4 is an explanatory view showing a cast iron stave cooler 1 disclosed as a third generation stave cooler by the pamphlet “Nippon Steel Stave Cooler”. FIG. 4 (a) is a front view, and FIG. 4 (b) is a front view. It is a side view. As shown in FIGS. 4 (a) and 4 (b), the main body 2 of the stave cooler 1 is made of cast iron, and a total of ten cooling pipes 3 that are bent in advance are cast in the main body 2 thereof. Placed and placed. The stave cooler 1 has a life of 10 years or longer by changing the material of the main body 2 or improving the density of the cooling pipe 3.
[0006]
On the other hand, FIG. 5 is explanatory drawing which shows the attachment structure to the iron skin 6 of the cast iron stave cooler 4 disclosed by Unexamined-Japanese-Patent No. 8-85808. As illustrated in FIG. 5, the main body 5 cast inside using the cooling pipe 7 bent in advance as a cooling water supply and discharge water channel is disposed inside the iron skin 6. The end of the cooling pipe 7 penetrates the through-hole provided in the iron skin 6 and is guided to the outside of the iron skin 6, and the exposed end of the cooling pipe 7 is protected by a protective pipe 8 arranged around the end. Protected. The protective tube 8 is attached to the iron skin 6 through a gas seal plate 9. The main body 5 of the stave cooler 4 is fixed to the iron shell 6 by mounting bolts 10a and 10b, washers 11a and 11b, and nuts 12a and 12b embedded in the main body 5 having a square head. Generally, the cast iron stave cooler 4 is attached to the iron shell 6 at two different height positions in the height direction of the blast furnace.
[0007]
However, if the cooling pipes 3 and 7 shown in FIG. 4 and FIG. 5 are used, the piping around the outside of the furnace becomes complicated, and the main bodies 2 and 5 need to be enlarged and the water supply equipment (not shown) must have a large capacity. For this reason, it cannot be used as a stave cooler for repair that needs to be replaced in a short time during operation.
[0008]
Further, in the mounting method shown in FIG. 5, since the mounting bolts 10a and 10b penetrate to the furnace inner surface, the mounting is performed before the loss of the cooling function of the main body 5 due to wear or wear due to long-term use. The support function of the bolts 10a and 10b is lost. As a result, all loads due to thermal expansion and warpage of the main body 5 are applied to the protective pipe 8 of the cooling pipe 7, so that a great amount of stress acts on the cooling pipe 7, causing crack damage, often in the blast furnace. There is a risk of serious accidents such as leakage of cooling water.
[0009]
FIG. 6 is an explanatory view showing another known attachment structure of the stave cooler 13 to the iron skin 14. In the mounting structure shown in FIG. 6, the cooling pipe 16 is attached to the iron skin 14 via an expansion tube 17 that is a gas seal hardware. According to this mounting structure, although the cooling pipe 16 cast into the main body 15 of the stave cooler 13 can be moved, the mounting for mounting the main body 15 on the iron skin 14 is similar to the mounting structure shown in FIG. Since the bolt 18 penetrates into the furnace, the support function of the mounting bolt 18 is lost prior to the loss of the cooling function of the main body 15, and the support function of the main body 15 is almost lost except for the telescopic tube 17. In the worst case, the telescopic tube 17 is damaged or the main body 15 is dropped.
[0010]
Therefore, Japanese Patent Laid-Open No. 52-8553 discloses a structure for cooling the mounting bolt 18 embedded in the main body 15 by the cooling water supplied from the cooling pipe 19, as shown in FIG. . However, this mounting structure requires the cooling pipe 19 and its water supply / drainage equipment. Usually, about 400 to 500 stave coolers are installed in one metallurgical furnace, so that the installation cost of the cooling pipe 19 and incidental facilities becomes enormous.
[0011]
In addition, as shown in FIG. 8, the structure which attaches the attachment bolt 18 by processing the tap hole 20 in the main body 15 of the stave cooler 13 is also considered. However, generally, the cast iron main body 15 is liable to crack due to thermal stress, and the bolt hole is particularly prone to stress concentration. For this reason, the mounting structure shown in FIG. 8 cannot be adopted.
[0012]
On the other hand, when constructing a new blast furnace or replacing a stave cooler when operation is interrupted for a long period of time, there is a growing demand for further extension of the life of the stave cooler itself and reduction of installation costs due to the extension of the blast furnace operating years. Such a request cannot be handled by a cast iron stave cooler. For this reason, a copper and copper alloy stave cooler having a long life and a simplified structure due to less wear, damage, thermal expansion and warping of the main body than a cast iron stave cooler is disclosed in No. 55-122810 and JP-A-11-293312.
[0013]
FIG. 9 is a plan view of a stave cooler 21 made of copper and a copper alloy disclosed in Japanese Patent Application Laid-Open No. 55-122810. A cooling water channel 23 is provided inside the main body 22 of the stave cooler 21 by machining. Further, the pipe member 24 for introducing and leading out the cooling water to the main body 22 is fixed to the main body 22 by welding.
[0014]
FIG. 10 is a plan view of a stave cooler 25 made of copper and a copper alloy disclosed in Japanese Patent Application Laid-Open No. 11-293312. The cooling water channel 27 in the main body 26 of the stave cooler 25 is integrally cast using a core when the main body 26 is manufactured. Further, the pipe material 28 for introducing and deriving the cooling water to and from the main body 26 is fixed to the main body 26 by welding similarly to the stave cooler 21 shown in FIG.
[0015]
9 and 10, the stave coolers 21 and 25 made of copper and copper alloy are less likely to be deformed due to cracks, wear, warpage, etc. of the main body and have a long life. In addition, considering the prevention of the occurrence of galvanic corrosion (corrosion between different metals), it is desirable that the materials of the pipe members 24 and 28 for introducing and deriving the cooling water into the main body are the same copper and copper alloy as the main bodies 22 and 26. . Further, when the pipe members 24 and 28 are made of copper and a copper alloy, they are inferior in strength compared to carbon steel. For the attachment, a method in which stress is not applied to the pipe members 24 and 28 by using the telescopic tube 17 illustrated in FIG. 6 is widely adopted.
[0016]
[Problems to be solved by the invention]
Since the copper and copper alloy stave coolers 21 and 25 as shown in FIGS. 9 and 10 are less likely to crack, providing the tap hole 20 in the main body 15 as shown in FIG. It is also desirable to prevent wear and tear. However, since the mounting bolt 18 as shown in FIG. 8 cannot intentionally be provided with the main body, the main bodies 21 and 25 of FIGS. Therefore, depending on the generated thermal stress, the metal fatigue progresses and the main bodies 21 and 25 are cracked. In addition, since cracks are fatigued, this problem may become more apparent in recent situations where the blast furnace service period tends to be prolonged.
[0017]
Some of the stave coolers attached to the blast furnace (for example, the stave cooler attached to the regular conical shaft portion) may be replaced in a short time during operation. However, when the copper and copper alloy stave coolers 21 and 25 as shown in FIGS. 9 and 10 are used as repair / replacement stave coolers, the repair / replacement stave cooler main body does not interfere with the existing stave cooler. It is necessary to hang from the furnace port part to the substantially central part in the furnace at the position and draw it in the substantially horizontal direction to the inner wall surface of the shaft part. For this reason, it is necessary to arrange a hanging tool on the inner surface of the furnace. At this time, since the slope between the suspended stave cooler and the iron skin is greatly different, there is a problem that it is difficult to draw the stave cooler to the iron skin, resulting in an increase in working time. Moreover, if the pipe material joined to the main body is made of copper and a copper alloy, the problem becomes more serious, and the strength is inferior to that of carbon steel, so there is a possibility that the pipe material may be bent or damaged. Sometimes it comes.
[0018]
The first object of the present invention is to provide a metallurgical furnace, such as a blast furnace, which can suppress or eliminate such problems of the prior art, that is, the occurrence of cracks caused by metal fatigue due to the generated thermal stress. The object is to provide a copper or copper alloy stave cooler for a metallurgical furnace for cooling and protecting the body, and a method for mounting the same.
[0019]
In addition to the first object, the second object of the present invention is that the replacement work can be performed in a short time even when used as a repair / replacement stave cooler, and further, the pipe material is bent or damaged. There is provided a stave cooler for a metallurgical furnace made of copper or a copper alloy and a method for attaching the same without fear.
[0020]
[Means for Solving the Problems]
The present invention has a main body disposed inside a metallurgical furnace, and the main body is fixedly disposed on an outer wall portion constituting the metallurgical furnace at one height position in the height direction of the metallurgical furnace. The distal end of the fixing member is disposed at a position farther from the main body than the respective distal ends of the cooling liquid supply pipe and the discharge pipe connected to the cooling liquid flow path provided inside the main body. This is a featured metal cooler stave cooler.
[0021]
Moreover, it is illustrated that the main body of the stave cooler for a metallurgical furnace according to the present invention is made of copper or a copper alloy.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a metallurgical furnace stave cooler and its mounting method according to the present invention will be described below in detail with reference to the accompanying drawings. In the following description, the case where the metallurgical furnace is the blast furnace 30 and the metal cooler stave cooler according to the present invention is mounted on the shaft portion of the blast furnace is taken as an example.
[0027]
FIG. 1 is a perspective view showing the shaft portion of the blast furnace 30 in a partially broken and omitted state. FIG. 2 is a cross-sectional view taken along the line AA in FIG.
As shown in FIG. 1, the shaft portion includes an iron skin 31 that forms part of a regular conical slope, and a stave cooler for a metallurgical furnace according to the present embodiment that is circumferentially arranged on the inner surface side of the iron skin 31. It is comprised by the main body 32 and the refractory material 33 with which the inner surface of this main body 32 was mounted | worn.
[0028]
The iron skin 31 constituting the shaft portion is mainly made of welded structural steel (SM material), and is constructed in a regular cone shape by welding a large number of small pieces having a plate thickness of about 30 to 100 mm. The main body 32 is made of copper or a copper alloy, and a cooling water passage (not shown) is provided inside. The arrangement and configuration of the cooling water flow path may be by well-known and conventional means. The main body 32 is arranged away from the inner surface of the iron skin 31 by a certain distance.
[0029]
Further, as shown in FIGS. 1 and 2, a refractory 33 is attached to the concavo-convex portion 34 on the plane on the main body 32 side.
Thus, in this Embodiment, many main bodies 32 with which the refractory material 33 was mounted | stacked are piled up, and the inner wall surface of a shaft part is comprised.
[0030]
In the present embodiment, the main body 32 includes fixing members 36 a and 36 b that are fixedly disposed on the iron shell 31 at one height position B in the height direction of the blast furnace 30. The fixing members 36a and 36b are rod-shaped members, and have sufficient strength to withstand a large external force generated by colliding with the inner surface of the iron shell 31 during mounting, as will be described later. Can be supported. In addition, tow metal fittings 37a and 37b are fixed to the tips of the fixing members 36a and 36b. In the present embodiment, the fixing member 36a, 36b is fixed to the main body 32 by providing a tap hole 38 in the main body 32 and screwing a screw portion provided at the tip of the fixing members 36a, 36b into the tap hole 38. However, it is not limited to such a form, and may be fixed by welding, for example.
[0031]
The fixing member 36 is exposed to the outside of the blast furnace 30 through the through holes 39 a and 39 b provided in the iron shell 31, and the ends to which the metal fittings 37 a and 37 b are fixed are exposed. Although omitted in FIG. 1 in order to prevent complication of the drawing, as shown in FIG. 2, an annular fixing washer 40 is mounted in the through hole 39c to support the fixing members 36a and 36b. At the same time, the through holes 39a and 39b are sealed.
[0032]
In the present embodiment, as shown in FIGS. 1 and 2, two fixing members 36a and 36b are provided at the height position B. Unlike the present embodiment, the blast furnace at the height position B is provided. One or two or more fixing members 36c may be provided in 30 circumferential directions.
[0033]
Further, four cooling water discharge pipes 41, 42, 45, 46 are attached to the upper part of the main body 32, and four cooling water supply pipes 43, 44, 47, 48 are attached to the lower part of the main body 32. . The cooling water discharge pipes 41, 42, 45, 46 and the cooling water supply pipes 43, 44, 47, 48 are all connected to a cooling water flow path (not shown) provided inside the main body 32. The cooling water supplied from the cooling water supply pipes 43, 44, 47, 48 cools the main body 32 by flowing through a cooling water flow path (not shown) provided inside the main body 32, and the cooling water discharge pipes 41, 42. , 45, 46.
[0034]
As shown in FIG. 2, the cooling water discharge pipes 41, 42, 45, 46 pass through the through holes 49 provided in the iron shell 31 and are exposed to the outside of the blast furnace 30. The cooling water supply pipes 43, 44, 47, 48 pass through the through holes 50 provided in the iron shell 31 and are exposed to the outside of the blast furnace 30.
[0035]
A disc-shaped sealing member 51 provided with two through-holes is welded to the through-holes 49, and telescopic tubes 52 are attached to the inner edges of these two through-holes. The ends of the telescopic pipes 52 are fixed to a seal member 53 provided at the ends of the cooling water discharge pipes 41, 42, 45, 46. Thereby, even if the cooling water discharge pipes 41, 42, 45, 46 are displaced due to the thermal expansion or contraction of the main body 32, in other words, the stress due to the thermal expansion is substantially eliminated in the main body 32. The sealability of the through hole 49 can be maintained while substantially absorbing the warp caused by the thermal expansion due to the temperature rise during the operation of the blast furnace 30.
[0036]
In addition, although illustration is abbreviate | omitted in FIG. 2, sealing with the cooling water supply pipes 43, 44, 47, and 48 and the through-hole 50 is also made | formed by the same means.
In the present embodiment, as shown in FIG. 2, cooling water discharge pipes 41, 42 in which the tips of the fixing members 36 a, 36 b are connected to a cooling water flow path (not shown) provided inside the main body 32. 45, 46 and the cooling water supply pipes 43, 44, 47, 48 are arranged at positions farther from the main body 32 than the respective tips.
[0037]
As described above, the metallurgical furnace stave cooler 32 of the present embodiment is disposed inside the shaft portion 30a of the blast furnace 30, and can substantially eliminate stress caused by thermal expansion due to temperature rise during operation of the blast furnace 30. In other words, in other words, the blast furnace 30 is attached to the iron skin 31 that is the outer wall portion constituting the blast furnace 30 so that the warp caused by the thermal expansion due to the temperature rise during operation can be substantially absorbed. .
[0038]
The metallurgical furnace stave cooler 32 of the present embodiment is configured as described above. Next, a method for mounting the metallurgical furnace stave cooler 32 will be described.
FIG. 3 is an explanatory view schematically showing a method of attaching the metallurgical furnace stave cooler 32 according to the present embodiment. The situation where the stave cooler 32 is replaced in a short time during the operation of the blast furnace 30 will be described with reference to FIG.
[0039]
First, before starting the replacement work, the fixing members 36a and 36b are screwed into the 32 tap holes 38 in advance. Two fixing members 36a, 36b are provided at the height position B, and are attached substantially parallel to the cooling water discharge pipes 41, 42, 45, 46 and the cooling water supply pipes 43, 44, 47, 48.
[0040]
The fixing members 36a and 36b have a length that contacts the iron skin 31 before the cooling water discharge pipes 41, 42, 45, and 46 and the cooling water supply pipes 43, 44, 47, and 48.
[0041]
In this manner, after the fixing members 36 a and 36 b are attached to the main body 32, the main body 32 is suspended by the wire 54 and then suspended in the furnace through the furnace port of the blast furnace 30. Thereafter, after the fixing members 36a and 36b reach a height substantially matching the through holes 39a and 39b, the pulling wire 55 is pulled out from the furnace through the through holes 39a and 39b, and the metal fittings 37a and 37b are pulled by the pulling wire 55. Then, the fixing members 36 a and 36 b are pulled, and the main body 32 is disposed at a predetermined position inside the iron skin 31.
[0042]
At this time, in the present embodiment, the fixing members 36a, 36b collide with the iron shell 31 before the cooling water discharge pipes 41, 42, 45, 46 and the cooling water supply pipes 43, 44, 47, 48. The accident that the cooling water discharge pipes 41, 42, 45, 46 and the cooling water supply pipes 43, 44, 47, 48 are damaged can be prevented, and the load on the fixing members 36a, 36b is gradually applied. If the position of the main body 32 is lowered, the inclination angle of the iron skin 31 and the inclination angle of the main body 32 naturally approach each other. For this reason, the main body 32 can be pulled and attached to the iron skin 31 without the cooling water discharge pipes 41, 42, 45, 46 and the cooling water supply pipes 43, 44, 47, 48 contacting the iron skin 31. It is.
[0043]
Thus, in the present embodiment, the metallurgical furnace stave cooler 32 is placed inside the blast furnace 30 so that stress caused by thermal expansion due to temperature rise during operation can be substantially eliminated, or thermal expansion. It attaches to the iron skin 31 which comprises the blast furnace 30 so that the curvature resulting from this can be absorbed substantially.
[0044]
Thus, according to the present embodiment, copper or a copper alloy for cooling and protecting the furnace body of a blast furnace, which can suppress or eliminate the occurrence of cracks due to metal fatigue due to the generated thermal stress. It was possible to provide a metallurgical furnace stave cooler 32 and its mounting method.
[0045]
Further, according to the present embodiment, even when used as a repair / replacement stave cooler, the replacement work can be performed in a short time, and the cooling water discharge pipes 41, 42, 45, 46 and the cooling water supply can be performed. Provided is a copper or copper alloy metallurgical furnace stave cooler 32 that can be smoothly exchanged without fear of bending or damaging the tubes 43, 44, 47, and 48, and a method of attaching the same. I was able to.
[0046]
Furthermore, according to the present embodiment, the stave cooler can be stably fixed and supported on the iron skin over a long period of time.
(Deformation)
In the embodiment, the case where the metallurgical furnace is a blast furnace is taken as an example. However, the present invention is not limited to a blast furnace, and is similarly applied to a metallurgical furnace other than the blast furnace.
[0047]
In the embodiment, the case where the metal-metal-furnace stave cooler is attached to the shaft portion of the blast furnace is taken as an example, but the present invention can also be applied to other parts other than the shaft portion.
[0048]
Moreover, in the embodiment, the case where the present invention is applied to a replacement metallurgical furnace stave cooler has been taken as an example, but it goes without saying that the present invention can be applied to, for example, a new blast furnace.
[0049]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to suppress or eliminate the occurrence of cracks caused by metal fatigue due to the generated thermal stress, for example, cooling and protecting a furnace body of a metallurgical furnace such as a blast furnace. It was possible to provide a stave cooler for a metallurgical furnace made of copper or copper alloy, and a method for mounting the same.
[0050]
Further, according to the present invention, even when used as a repair / replacement stave cooler, the replacement work can be performed in a short time, and there is no risk of bending or damaging the pipe material. Stab cooler for metallurgical furnace and its mounting method.
[0051]
The significance of the present invention having such an effect is remarkable.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a shaft portion of a blast furnace in a partially broken and omitted state.
FIG. 2 is a cross-sectional view taken along the line AA in FIG.
FIG. 3 is an explanatory view schematically showing a mounting method of a metal cooler stave cooler according to an embodiment.
FIG. 4 is an explanatory view showing a cast iron stave cooler 1 disclosed as a third generation stave cooler by the pamphlet “Nippon Steel Stave Cooler”. FIG. 6 (a) is a front view, and FIG. 6 (b) is a front view. It is a side view.
FIG. 5 is an explanatory view showing a mounting structure of a cast iron stave cooler disclosed in Japanese Patent Application Laid-Open No. 8-85808.
FIG. 6 is an explanatory view showing another known attachment structure to the iron skin of the stave cooler.
FIG. 7 is an explanatory view showing a structure for attaching a stave cooler to an iron skin disclosed in Japanese Patent Laid-Open No. 52-8553.
FIG. 8 is an explanatory view showing a structure for attaching a mounting bolt by machining a tap hole in the main body of the stave cooler.
FIG. 9 is a plan view of a copper and copper alloy stave cooler disclosed in Japanese Patent Application Laid-Open No. 55-122810.
FIG. 10 is a plan view of a stave cooler made of copper and a copper alloy disclosed by Japanese Patent Laid-Open No. 11-293312.
[Explanation of symbols]
30 Blast furnace 31 Iron skin 32c Stave cooler 32c 'for metallurgical furnace Main body 36c Fixing member B One height position

Claims (2)

The main body has a main body disposed inside the metallurgical furnace, and the main body includes a fixing member fixedly disposed on an outer wall portion constituting the metallurgical furnace at one height position in the height direction of the metallurgical furnace. The front end of the fixing member is disposed at a position farther from the main body than the front ends of the cooling liquid supply pipe and the discharge pipe connected to the cooling liquid flow path provided inside the main body. A stave cooler for metallurgical furnaces. The metal cooler stave cooler according to claim 1, wherein a main body of the metal cooler stave cooler is made of copper or a copper alloy .

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