JPH101705A - Blast furnace air flow control valve - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To facilitate removal and replacement of a valve body and to suppress generation of thermal stress in the valve body. SOLUTION: In an air volume control valve installed in a blower branch pipe that blows hot air from a tuyere at a lower part of a blast furnace, a valve box having a horizontal hole 5 formed in a direction orthogonal to a direction of a flow path 4 through which hot air passes, A valve having a substantially cylindrical shape, a hot air passage hole 2 is formed in a penetrating state in a direction perpendicular to the axis thereof, and is disposed rotatably and axially movable in a lateral hole 5 of the valve box. Body 1 and
The rotary drive shaft 11 is detachably fitted in the valve body 1 in the axial direction. The flange 20 is rotatably supported on the rotary drive shaft 11 and detachably attached to the valve box.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air flow control valve installed in a blower pipe for blowing hot air from a tuyere at a lower part of a blast furnace.

[0002]

2. Description of the Related Art At the tuyere at the lower part of a blast furnace, there are provided a plurality of blast sub-tubes for blowing hot air. In order to independently control the flow rate in each blast sub-tube, each blast sub-tube is provided. An air flow control valve is installed.

[0003] The air volume control valve for the blast furnace ventilation branch pipe is required not only to have sufficient heat resistance and strength, but also to be able to perform reliable control over a long period of time. Therefore,
2. Description of the Related Art Various types of structures of air flow control valves for blast furnace ventilation branch pipes have been conventionally proposed.

FIG. 8 is a cross-sectional view showing a conventional air flow control valve described in Japanese Utility Model Publication No. Hei 4-7175 together with a blast furnace air supply branch, and FIG. 9 is an enlarged cross-sectional view of the air flow control valve in FIG.

[0005] As shown in FIG. 9, a ball-shaped valve element 54 having an opening 53 penetrating through the center is used as the air flow control valve 52 arranged on the upstream side of the duden stock 51 shown in FIG. This is a blower branch air volume control valve, and the ball-shaped valve element 54 is housed in a valve box brick 55. The valve element 54 is formed of a castable, and has a valve element frame 58 on water cooling shafts 56 and 57 disposed on both sides of the valve element 54.
Are connected via The water cooling shafts 56 and 57 are
It is supported at 9,60. In addition, one water cooling shaft 56
Has a structure that protrudes from the flange surface 61 on the side surface of the valve box and is rotated when the valve 54 is opened and closed.

In the air volume control valve shown in FIGS. 8 and 9, when the electric cylinder 62 is driven, the rotation lever 63 is rotated, and the area of the opening 53 viewed from the flow path direction changes. Can be controlled.

However, in the air volume control valve 52 shown in FIGS. 8 and 9, the ball-shaped valve element 54 is
5 so that the valve body 54 can be used for repair or the like.
When replacing the valve, only the valve element 54 cannot be removed, and the refractory in the valve box disposed around the valve element 54 needs to be largely dismantled and removed. There was a problem that it took time.

Further, since the valve body 54 formed by castable is water-cooled, the valve body 54 is thermally cooled.
Cracks are easily formed, which is not preferable in terms of life.

On the other hand, Japanese Patent Application Laid-Open No. 6-88114 discloses a blast furnace feed rate control valve which makes it possible to easily repair the valve element.

FIG. 10 is a cross-sectional view showing a conventional air flow control valve described in Japanese Patent Application Laid-Open No. 6-88114 together with a blast furnace air supply branch pipe, and FIG. 11 is an enlarged cross-sectional view of the air flow control valve in FIG.

In the apparatus described in the publication, the air volume control valve 71 is installed in a passage of a blower branch pipe 74 disposed between the hot air annular pipe 72 and the tuyere 73. As shown in FIG. 11, in the air volume control valve 71, a hose 75
The valve body 77 is formed by molding an endless refractory (castable) at the tip of a rotary shaft 76 that is water-cooled with cooling water supplied from the cooling unit. The tip of the valve body 77 is cut obliquely, and is inserted obliquely into the passage of the blower branch pipe 74 as shown in FIG. The rotation shaft 76 of the valve body 77 is rotatably supported by a bearing 79 fixed to a bearing housing 78. A bearing housing fixing flange 80 is integrally formed at an end of the bearing housing 78 opposite to the valve body 77, and the bearing housing fixing flange 80 is fixed to a ventilation branch pipe side flange 81 by a bolt 82. As a result, the air volume control valve 71 is attached to the ventilation branch pipe 74. Further, a geared motor 83 for rotating the rotation shaft 76 is provided at an end of the rotation shaft 76 opposite to the valve body 77. The geared motor 83 is supported by a bracket 84 connected to a bearing housing fixing flange 80.

In the air volume control valve shown in FIGS. 10 and 11, a valve 77 is rotated by a geared motor 83 via a rotary shaft 76 so that the valve
In the air volume control valve shown in FIGS. 10 and 11 in which the amount of protrusion of
The valve body 77 can be easily taken out together with the bearing 79 and the bearing housing 78, so that the valve body 77 can be easily replaced.

However, Japanese Patent Application Laid-Open No. Hei 6-88114 discloses
In the air volume control valve described in Japanese Patent Publication No. 4-71,
Similarly to the air volume control valve described in Japanese Patent Publication No. 75-75, since the valve body 77 itself is water-cooled, there is a problem that the valve body 77 is easily damaged by thermal stress. In particular, JP-A-6-881
In the air volume control valve described in Japanese Patent Application Publication No. 14, since the tip of the valve body 77 has an acute angle and is heated on two sides, the temperature tends to be high and the proof stress may be reduced.

[0014]

SUMMARY OF THE INVENTION Accordingly, the present invention makes it possible to easily remove and replace a valve body.
It is an object to suppress generation of thermal stress in a valve body.

[0015]

An air flow control valve for a blast furnace air blower branch pipe according to the present invention is an air flow control valve installed in a blower branch pipe that blows hot air from a tuyere at a lower part of a blast furnace furnace. A valve box in which a horizontal hole is formed in a direction orthogonal to the direction,
A valve element having a substantially columnar shape, a hot air passage hole formed in a penetrating state in a direction perpendicular to the axis thereof, and disposed rotatably and axially movable in a lateral hole of the valve box. And a rotary drive shaft that is removably fitted in the valve body in the axial direction,
And a support member rotatably supporting the rotary drive shaft and detachably attached to the valve box.

[0016] The valve is a valve body having a non-water-cooled refractory structure. In the air volume control valve of the blower branch pipe according to the present invention, the valve body has a substantially cylindrical shape, and a horizontal hole is formed in the valve box in a direction perpendicular to the direction of the flow path through which the hot air passes. The body can be inserted and removed. Thus, at the time of repair, the valve element can be removed and replaced by simply removing the support member that supports the rotary drive shaft, for example, the flange.

Further, since the valve body has a non-water-cooled refractory structure, thermal stress is hardly generated in the valve body, and a long life can be obtained.

[0018]

FIG. 1 is a sectional view showing an embodiment of an air flow control valve for a blast furnace air blower branch pipe according to the present invention, FIG. 2 is a cross-sectional view of the air flow control valve shown in FIG. FIG. 2 is a sectional view taken along line BB of the air volume control valve shown in FIG. 1. FIG. 4 is an exploded sectional view of the air volume control valve shown in FIG. The valve body 1 has a cylindrical shape as a whole as shown in FIG. 5 alone, and has a passage hole 2 penetrating therethrough as a hot air passage in a direction orthogonal to the axial direction thereof. The valve element 1 is rotatably mounted inside the refractory 3 in the valve box through which hot air passes, as described below.

A flow path 4 through which hot air passes is formed in the refractory 3 in the valve box, and a horizontal hole 5 is formed in a direction perpendicular to the flow path 4 so as to penetrate therethrough. The lateral hole 5 has the same diameter over its entire length. The inner diameter of the passage hole 2 is set substantially equal to the inner diameter of the flow path 4. The outer diameter of the valve element 1 is set slightly smaller than the inner diameter of the lateral hole 5, and the valve element 1 is fitted into the lateral hole 5 so as to be rotatable and movable in the axial direction. Cylindrical refractory spacers 6 and 7 are arranged on both sides of the valve element 1 in the axial direction. The outer diameters of these refractory spacers 6, 7 are selected to be substantially equal to the inner diameter of the lateral hole 5, and are fitted in the lateral hole 5 with the valve element 1 interposed therebetween. Through holes 8 and 9 are formed in the central axes of the refractory spacers 6 and 7, a refractory rotating shaft 10 is fitted in the through hole 8, and a water-cooled drive rotating shaft 11 is fitted in the through hole 9. Have been. The tips of the refractory rotation shaft 10 and the water-cooled drive rotation shaft 11 slightly protrude from the side surfaces of the refractory spacers 6 and 7 facing each other.

At one end (left side in FIG. 1) of the valve body 1 in the axial direction, as shown in FIG.
2 are formed, and the refractory rotating shaft 10
Are fitted. As shown in FIG. 6B, an oval receiving hole 13 is formed at the other axial end (right side in FIG. 1) of the valve element 1.
An oval tip metal fitting 14 (see FIG. 7) formed at the tip of the water-cooling drive rotary shaft 11 is fitted into the shaft.

A castable 15 is disposed on a side of the one refractory spacer 6 opposite to the valve element 1, and a flange 16 is provided to cover the castable 15 from outside. This flange 16 is a valve box side flange 1 attached to a valve box steel 17 provided to cover the refractory 3 in the valve box.
7a is fixed by bolts 18.

Similarly, the valve element 1 of the other refractory spacer 7
A castable 19 is disposed on the side opposite to the side, and a flange 20 is provided to cover the castable 19 from outside.
Is provided. This flange 20 is also fixed to the valve box side flange 17a of the valve box steel 17 with bolts 18. The castable 19 and the flange 20 have a water-cooled drive shaft 1
1, through holes 21 and 22 are formed. In the portion of the through hole 21, a stopper 23 is fixed to the water-cooling drive rotation shaft 11. Further, the water-cooled drive rotary shaft 11 is rotatably supported by a bearing 24 attached to the flange 20.

At the end of the water-cooling drive shaft 11 opposite to the valve body 1, an arm 25 for rotating the water-cooling drive shaft 11 and cooling water is supplied into the water-cooling drive shaft 11. Water supply pipe 26 is provided.

The refractory spacer 7 and the water-cooled drive shaft 1
1, the castable 19, the stopper 23, the bearing 24, the arm 25, the water supply pipe 26, and the like constitute a detachable portion 27 (see FIG. 4) that can be integrally removed from the valve box. The refractory 3 in the valve box, the steel shell 17 of the valve box, and the like constitute a valve box section 28.

Next, an example of an assembling and disassembling procedure in the above-described air volume control valve will be described.

First, the flange 16 on which the castables 15 are installed is fixed to the valve box side flange 17a by bolts 18. Next, the refractory spacer 6 fitted with the refractory rotating shaft 10 is inserted into the lateral hole 5. Next, the valve element 1 is moved along the axial direction of the lateral hole 5, inserted into the lateral hole 5, and the tip of the refractory rotating shaft 10 is fitted into the circular receiving hole 12 of the valve element 1. Next, the attachment / detachment portion 27 is moved along the axial direction of the horizontal hole 5, inserted into the horizontal hole 5, and inserted into the oval receiving hole 13 of the valve element 1 into the oval tip metal fitting 14 of the tip of the water-cooling drive rotary shaft 11. Is fitted. Finally, the flange 20 is connected to the valve box side flange 17a.
Is fixed by the bolts 18 to complete the assembling work.

Next, at the time of repair work such as replacement of the valve body 1, first, the bolt 18 of the flange 20 is loosened and the detachable portion 2 is removed.
7 is integrally removed from the valve box 28. Next, the valve body 1 is taken out alone. At this stage, the disassembling operation is completed. Next, a new valve element 1 is inserted into the lateral hole 5. Finally, the refractory spacer 7 of the attachment / detachment part 27, the water-cooling drive rotating shaft 11, and the castable 19 are inserted into the lateral hole 5, and the flange 20 is fixed to the valve box side flange 17a with the bolt 18, thereby completing the repair work.

As described above, according to the present embodiment, the valve element 1 can be replaced only by loosening the bolt 18 connecting the flange 20 and the valve box side flange 17a, so that the repair work is very difficult. Simplified.

During operation of the blast furnace, hot air flows through the above-mentioned air volume control valve. However, since the valve element 1 has a non-water-cooled refractory structure, the temperature gradient inside the valve element 1 is small and thermal stress is suppressed. Can be

Further, since the inner diameter of the passage hole 2 is set substantially equal to the inner diameter of the flow path 4, when the valve is fully opened, the valve body 1 does not obstruct the flow of the fluid and the pressure loss is small.

Further, since the portion for rotatably supporting the valve element 1 is cooled by the water-cooling drive rotary shaft 11, there is no possibility that a rotation failure due to thermal expansion or burn-in occurs.

[0032]

【The invention's effect】

(1) When the valve body is damaged, only the valve body can be removed without dismantling the refractory on the valve box side, thereby greatly reducing repair costs.

(2) When the valve element has a non-water-cooled refractory structure, the temperature gradient inside the valve element is small, thermal stress is suppressed, and a long life is obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an embodiment of an air volume control valve for a blast furnace ventilation branch pipe of the present invention.

FIG. 2 is a sectional view taken along line AA of the air volume control valve shown in FIG.

FIG. 3 is a sectional view taken along line BB of the air volume control valve shown in FIG. 1;

FIG. 4 is an exploded sectional view of the air volume control valve shown in FIG.

FIG. 5 is a perspective view showing a valve body alone.

FIG. 6A is a cross-sectional view of the valve body shown in FIG.
FIG. 5B is a sectional view taken along line DD of the valve body shown in FIG. 4.

FIG. 7 is a partial perspective view showing an oval tip metal member formed at the tip of a water-cooling drive rotary shaft.

FIG. 8 is a cross-sectional view showing a conventional air volume control valve together with a blast furnace ventilation branch pipe.

FIG. 9 is an enlarged sectional view of the air volume control valve in FIG.

FIG. 10 is a cross-sectional view showing another conventional air volume control valve together with a blast furnace air supply pipe;

FIG. 11 is an enlarged sectional view of the air volume control valve in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Valve body, 2 ... Passage hole, 3 ... Refractory in a valve box, 4 ... Flow path,
5 ... side hole, 6,7 ... refractory spacer, 8, 9 ... through hole,
DESCRIPTION OF SYMBOLS 10 ... Refractory rotating shaft, 11 ... Water-cooling drive rotating shaft, 12 ... Circular receiving hole, 13 ... Oval receiving hole, 14 ... Tip hardware, 15
... castable, 16 ... flange, 17 ... valve case steel, 1
8 bolt, 19 castable, 20 flange, 2
1, 22 ... through-hole, 23 ... stopper, 24 ... bearing, 25
... Arm, 26 ... Water pipe, 27 ... Removable part, 28 ... Valve part, 51 ... Duden stock, 52 ... Air volume control valve, 5
3 ... opening, 54 ... valve element, 55 ... valve box brick, 56, 57
... water-cooled shaft, 58 ... valve body frame, 59, 60 ... bearing, 6
DESCRIPTION OF SYMBOLS 1 ... Flange surface, 62 ... Electric cylinder, 63 ... Rotating lever, 71 ... Air volume control valve, 72 ... Hot air ring tube, 73 ... Tuyere, 74 ... Blower branch tube, 75 ... Hose, 76 ... Rotating shaft, 7
7 ... valve element, 78 ... bearing housing, 79 ... bearing, 80 ...
Flange for fixing bearing housing, 81 ... Flange on the side of air blower, 82 ... Bolt, 83 ... Geared motor, 84 ... Bracket

Claims (5)

[Claims] An air volume control valve installed in a blower branch pipe for blowing hot air from a tuyere at a lower part of a blast furnace, comprising: a valve box having a horizontal hole formed in a direction orthogonal to a direction of a flow path through which hot air passes; A valve body having a cylindrical shape, a hot air passage hole formed in a penetrating state in a direction perpendicular to the axis thereof, and a rotatable and axially movable valve body disposed in a lateral hole of the valve box; A rotary drive shaft that is removably fitted in the valve body in the axial direction, and a support member that rotatably supports the rotary drive shaft and is detachably attached to the valve box. An air flow control valve for a blast furnace air branch pipe. 2. The air flow control valve according to claim 1, wherein the valve element is a valve element having a non-water-cooled refractory structure. 3. The air flow control valve according to claim 1, wherein the support member is a flange detachably attached to the valve box with a bolt. 4. The air flow control valve according to claim 1, wherein the side holes have the same diameter over the entire length thereof. 5. The air flow control valve for a blast furnace blower branch according to claim 1, wherein the rotary drive shaft is a water-cooled rotary drive shaft.