JPH07113111A - Hood for opening part of metal refining furnace - Google Patents

Abstract

PURPOSE:To provide a hood for the furnace opening part, in which soot and dust, etc., are difficult to stick and even if the soot and dust are stuck, the stuck material is easily removed. CONSTITUTION:The hood 21 for furnace opening part is formed with cooling water pipes 18a-18f extending in the direction introducing exhaust gas. The inner surface side of deeply contracted gap formed between mutual adjacent cooling water pipes 18a-18f, is filled up with welding part 20. A skirt 22 is formed with spiral cooling water pipes 18x-18z, too. The gap between mutual adjacent cooling water pipes 18x-18z is filled up with the welding part 22 from the inner surface side. At the time of flowing exhaust gas containing much soots and dusts at the inner surface side of the hood 21 for furnace opening part and the skirt 22, the stuck material is difficult to form because the inner surface side is smooth, and even if the stuck material is formed, the stuck material can easily be removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throat cover of a metal refining furnace such as a converter for steelmaking.

[0002]

2. Description of the Related Art Conventionally, a converter for steelmaking is provided with a furnace port cover as shown in FIG. The furnace port cover includes a furnace port hood 1 and a skirt 2. The skirt 2 covers the upper opening of the converter 3. The furnace hood 1 extends obliquely upward from the upper part of the skirt 2 and guides the exhaust gas generated from the converter 3 to the cooler 4. The exhaust gas cooled by the cooler 4 is cleaned via the dust collector 5 and the separator 6, and the flow rate is measured by the flow meter 7.

FIG. 9 shows an example of a concrete structure of the furnace hood 1 and the skirt 2 shown in FIG. The peripheral wall of the furnace hood 1 has a plurality of water cooling pipes 8a extending in a direction in which exhaust gas is guided.
It is formed by 8b, 8c, 8d, 8e and 8f. Cooling water is supplied to each of the water cooling pipes 8a to 8f from a lower branch pipe 9i, and the cooling water is discharged from an upper branch pipe 9o.
The peripheral wall of the skirt 2 has spiral water cooling tubes 8x, 8y, 8z.
Formed by. The prior art of forming a skirt by a spiral copper tube is disclosed in, for example, Japanese Patent Laid-Open No. 1-92305.
It is disclosed in the publication.

[0004]

A large amount of dust is generated during operation from a metal refining furnace such as a converter. In a steelmaking converter or the like, the slag on the surface of the molten steel or the molten steel itself scatters during oxygen blowing. These dust particles and scattered materials easily attach to the surfaces of the water cooling tubes 8a to 8f and 8x to 8z. Particularly, since deep recesses are formed between the adjacent water cooling pipes 8a to 8f and 8x to 8z, dust and the like are likely to be deposited using these recesses as a foothold. When a large amount of dust and the like is accumulated on the inner surfaces of the furnace hood 1 and the skirt 2, there is a possibility that the cross-sectional area of the flow path that guides the exhaust gas may be reduced or that the thick deposit layer may suddenly drop. Therefore, the furnace hood 1
It is necessary to remove the adhesion layer from the inner surface of the skirt 2 or the skirt 2 as needed or periodically. However, the water cooling pipe 8a-
Since 8f and 8x to 8z are tubes having a circular cross section, deep constricted recesses are formed between adjacent ones, and it is difficult to remove the deposits that bite into these recesses.

An object of the present invention is to provide a furnace port cover for a metal refining furnace in which dust particles and scattered materials are unlikely to adhere, and even if they adhere, the adhered materials can be easily removed.

[0006]

According to the present invention, there is provided a metal smelting furnace furnace cover which covers a furnace opening of a metal smelting furnace and guides exhaust gas generated from the metal smelting furnace to a treatment facility. The water-cooled pipes have a peripheral wall formed by being installed as much as possible, and include a passage for guiding exhaust gas, and the inner surface side of the peripheral wall of the passage has a surface smoothed in a recess between adjacent water-cooled pipes. Is a throat cover of a metal refining furnace, which is characterized in that a filling part is formed.

Further, the filling portion of the recess of the present invention is characterized in that it is formed by overlay welding of a water cooling pipe.

The metal refining furnace of the present invention is a converter for steelmaking.

[0009]

According to the present invention, the exhaust gas is guided from the furnace opening of the metal refining furnace to the treatment facility through the passage having the peripheral wall formed by the plurality of metal water cooling pipes having the circular cross section. On the inner surface side of the peripheral wall, a filling portion is formed in a recess which is a deeply constricted portion between adjacent water cooling tubes. Since the surface is smooth and there is no deep constriction, it is difficult for dust to adhere to the surface of the water cooling pipe. Further, even if dust or the like adheres, the adhered matter does not cut into the recess, so that the adhered matter can be easily removed.

Further, according to the present invention, the filling of the recesses formed between the water cooling pipes is performed at the filling portion formed by build-up welding of the water cooling pipes. Since it is done by overlay welding,
It is easy to form a filling part that matches the shape of the recess between the water cooling pipes. In addition, the joint strength between the water cooling pipes is increased and the airtightness is also improved.

Further, according to the present invention, since the metal refining furnace is a converter for steelmaking, a large amount of dust is contained in the high temperature exhaust gas. Since the inner surface of the peripheral wall formed by the water cooling pipe is smoothed by the filling portion, it is easy to remove the deposits,
The time required to repair the device can be shortened.

[0012]

1 to 6 show the construction of a furnace mouth hood for a converter according to an embodiment of the present invention. FIG. 1 shows a partial configuration as seen from the inner surface side of the furnace hood, and FIG. 2 shows a sectional view as seen from the section line II-II of FIG. FIG. 3 shows a concrete structure of the furnace hood. 4, 5 and 6 show the structure of the skirt, FIG. 4 is a plan view thereof, FIG. 5 is a front view thereof, and FIG. 6 is a sectional view taken along the section line VI-VI of FIG.

Referring to FIGS. 1 and 2, a water cooling pipe 18
a, 18b, 18c, 18d, 18e, 18f extend in the direction of guiding the exhaust gas, and branch pipes 19i,
19o respectively. Cooling water is supplied from the branch pipe 19i and cools the exhaust gas while flowing through the water cooling pipes 18a to 18f from the lower side to the upper side. Upper branch pipe 19
From o, the used cooling water is discharged. Water cooling tube 18
Below the a to 18f, the water cooling pipe 18 that is spirally wound.
x, 18y, 18z are provided. Spiral water cooling tube 18
x-18z are mutually connected in series, and cooling water flows.

Each water cooling pipe 18a-18f, 18x-18z
For example, a carbon steel pipe for high temperature piping (STPT), a carbon steel pipe for pressure piping (STPG), a carbon steel pipe for boiler / heat exchanger (STB), etc. are used. Each water cooling pipe 18a-
Since the cross-sectional shape of 18f and 18x to 18z is circular,
Even if they are installed as much as possible, a considerable gap is formed between adjacent ones so as to be deeply constricted. The recesses formed by the gaps formed between the water cooling pipes 18a to 18f and 18x to 18z are filled with the welded portion 20 which is welded by internal welding. Water cooling pipe 18 extending in the direction of guiding the exhaust gas
The a to 18f form the furnace opening hood 21, and the water-cooled tubes 18x to 18z spirally wound form the skirt 22. The welded portion 20 is formed on the inner surface side of the furnace opening hood 21 and the skirt 22 and smoothes the inner peripheral surface. This makes it difficult for dust and the like to adhere, can easily remove the adhered dust, and improves strength and airtightness.

As shown in FIG. 3, the furnace port hood 21 has a vertical portion and an inclined portion extending above the vertical portion. The lower end of the vertical portion is surrounded by the skirt 22. Skirt 22
Covers the opening of the converter 23. A fixed mount 24 is provided on the furnace hood 21. The fixed base 24 is mounted on the moving carriage 25. The upper end of the furnace opening hood 21 is connected to a duct 27 via a bellows 26. The skirt 22 can be displaced up and down by a cylinder 28. The skirt 22 is lowered and the converter 23
Cover the opening. When the skirt 22 is raised, there is a gap between the opening of the converter 23 and the lower surface of the skirt 22, so that the converter 23 can be tilted. With the skirt 22 raised and separated from the duct 23, the furnace hood 21 is moved by the moving carriage 25 into the converter 23.
The inner surface can be repaired by moving it from the opening. According to the present embodiment, since the deposits on the inner surface can be easily removed, the repair work can be completed in a short time and the operating rate of the device can be increased.

When steel is produced by the converter 23, oxygen is blown by using the lance 29. Since the exhaust gas generated during the operation of the converter has a high temperature, cooling water is supplied from the water supply ports 30a and 30b. The supplied cooling water flows through the water cooling pipe which constitutes the furnace hood 21, and is discharged from the drainage ports 31 a and 31 b above the furnace hood 21. Skirt 22
A water supply port 32 and a drain port 33 are provided to cool the water. The furnace hood 21 is also provided with a lance hole 34 for inserting the lance 29 and an auxiliary material hole 35 for introducing the auxiliary material. Lance hole 34 and auxiliary material hole 35
Has an airtight structure that prevents exhaust gas from leaking.

A flange 36 is provided on the upper edge of the skirt 22 shown in FIGS. 4 and 5. Flange 36
A water cooling pipe 37 is provided immediately below. Further, water cooling tubes 18x to 18z that are spirally wound are provided below the water cooling tubes 18x to 18z, respectively. In order to reinforce the skirt 22 formed by these spiral water cooling pipes 18x to 18z, the rib 3
8 and 39 are provided respectively. The cooling water is supplied from the water supply pipe 40 connected to the water supply port 32 of FIG. Water supply pipe 4
The tip of 0 has two connecting portions 41a and 41b of the branch pipe 41.
Are connected to the water cooling tubes respectively. Connection part 41a
Is connected to the lowermost water cooling pipe of the water cooling pipes. The connecting portion 41b is connected to the water cooling pipe 18m located at a substantially intermediate position. Since each water cooling pipe is spirally wound, the cooling water supplied to the lower stage sequentially moves to the upper stage. When the cooling water supplied to the lowermost stage reaches the water cooling pipe 18m in the middle stage, it flows into the water cooling pipe 37 from the connecting portion 42a of the branch pipe 42. The connecting portion 42a of the branch pipe 42 is arranged upstream of the connecting portion 41b of the branch pipe 41 with respect to the water cooling pipe 18m. A partition wall 18 is provided between the connecting portion 42a and the connecting portion 41b.
n is provided. The cooling water supplied from the connection portion 41b to the water cooling pipe 18m sequentially rises in the spiral water cooling pipe and reaches the connection portion 42b via the water cooling pipes 18z, 18y, 18x.
The cooling water flowing into the branch pipe 42 from the connecting portion 42b also moves to the water cooling pipe 37. The diameter of the water cooling pipe 37 is 18 m,
The diameter of the cooling water is larger than the diameter of 18x to 18z, and the flowing directions of the cooling water inside are opposite. Adjacent to the connection position of the branch pipe 42,
The water cooling pipe 37 is connected to a drain pipe 43 connected to the drain port 33 of FIG. The water cooling pipe 3 is connected to the drain pipe 43.
The flow direction of the cooling water in 7 is the opposite direction. Branch pipe 42
A partition wall 37a is provided between the drain pipe 43 and the drain pipe 43. As shown in FIG. 6, the position of the drainage pipe 43 is slightly higher than that of the end pipe 42. This is because the cooling water, which is used in the water cooling pipe 43 and has a high temperature, is drained from the drain pipe 43.

FIG. 7 shows a cooling water connection structure according to another embodiment of the present invention. In the present embodiment, the interior of the lower water conduit 44 is divided into a plurality of chambers 46 by the partition wall 45. The upper water conduit 47 is also divided into a plurality of chambers 49 by partition walls 48. Cooling water pipes 50a, 50 between the rooms 46, 49
b, 50c, 50d, 50e, 50f are connected, and the flow direction of the cooling water is reversed between the adjacent cooling water pipes 50a to 50f. The cooling water pipes 50a to 50f form a peripheral wall of a cylindrical passage, and a filling portion formed by welding is formed on the inner surface side thereof as in the embodiment of FIG. In addition, the cooling water pipe 50a-
The extending direction of 50f may be parallel to, perpendicular to, or intersecting with the direction of guiding the exhaust gas at another angle.

Although the converter 23 is used as the metal refining furnace in the above embodiments, it may be a blast furnace or an electric furnace. Further, the metal to be refined is not limited to steel, but may be alloy steel such as stainless steel, non-ferrous metal, or non-ferrous alloy. Further, the metal water-cooled pipe may be made of stainless steel, copper, titanium or the like, as well as steel. In addition, the filling section,
Although it is formed by overlay welding, the recesses formed in the gaps between the water cooling pipes may be filled by thermal spraying or the like.

[0020]

As described above, according to the present invention, the inner surface side of the passage having the circular wall and the peripheral wall formed by the plurality of metal water-cooled pipes which are in contact with each other as much as possible is smoothed.
Since there is no deeply constricted portion, dust particles contained in the exhaust gas generated from the metal refining furnace are hard to adhere, and even if they adhere, they can be easily removed.

Further, according to the present invention, the water cooling pipes are welded to each other to form the filling portion, so that the mechanical strength and airtightness of the peripheral wall of the passage for guiding the exhaust gas are also improved.

Further, according to the present invention, since the metal refining furnace is a converter for steelmaking, high temperature exhaust gas and a large amount of dust are generated. Since the filling portion is formed between the water-cooled tubes and the surface is smoothed, it is easy to remove the deposits from the surface of the water-cooled tube, and the time required for repair and the like can be shortened.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a part of an embodiment of the present invention.

FIG. 2 is a sectional view taken along the section line II-II in FIG.

FIG. 3 is a front view showing a part of the steelmaking equipment including the embodiment of FIG. 1 in a cutaway manner.

4 is a plan view of the skirt 22 of FIG.

5 is a front view of the skirt 22 of FIG.

6 is a cross-sectional view taken along the section line VI-VI in FIG.

FIG. 7 is a simplified cross-sectional view showing a method of supplying cooling water according to another embodiment of the present invention.

FIG. 8 is a simplified perspective view showing a schematic configuration of a conventional converter steelmaking facility.

FIG. 9 is a partial perspective view showing a typical prior art structure for the furnace hood 1 and skirt 2 shown in FIG.

[Explanation of symbols]

 18a to 18f, 18m, 18x to 18z Water cooling pipe 19i, 19o Branch pipe 20 Welding part 21 Furnace hood 22 Skirt 23 Converter 30, 32 Water inlet 31, 33 Drainage port 37 Water cooling pipe 40 Water feed pipe 41, 42 Branch pipe 43 Drainage pipe 44,47 Water conveyance pipe 45,48 Partition wall 46,49 Room 50a-50f Water cooling pipe

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Makoto Sudo 4976 Nomura Minami-cho, Shinnanyo-shi, Yamaguchi Prefecture Shunan Steel Works (72) Inventor Isao Ueki 4976 Nomura-minami-cho, Shinnanyo-shi, Yamaguchi Nisshin Shunan Steel Works, Ltd.

Claims (3)

[Claims] 1. A furnace opening cover of a metal refining furnace that covers the furnace opening of the metal refining furnace and guides exhaust gas generated from the metal refining furnace to a treatment facility, with a plurality of metal water-cooled pipes having circular cross sections being installed as much as possible. Includes a passage for guiding exhaust gas, and a filling portion having a smoothed surface is formed in a recess between adjacent water cooling pipes on an inner surface side of the passage. The throat cover of a metal refining furnace characterized by being. 2. The throat cover of a metal refining furnace according to claim 1, wherein the filling portion of the recess is formed by overlay welding of a water cooling pipe. 3. The furnace port cover of the metal refining furnace according to claim 1, wherein the metal refining furnace is a converter for steelmaking.