JP2000018834A - Pressurizing hood shield device in sintering facility and its sealing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressurizing hood seal device which can obtain enough pressure loss without needing a seal piece and is capable of blowing in of gas, in a downward suction type sintering machine. SOLUTION: The shape of the end in width direction of the bottom of the skirt part 4 of the pressurizing hood 3 provided on the sintering pallet 1 of a downward suction system on sintering machine is made in labyrinth structure, and a plate 13 is installed on the sintering pallet 1 in the positions opposed to each other between the labyrinth parts of this labyrinth structure, thus it is made into alternate labyrinth structure. A part of the bottom of a comb- shaped labyrinth structure is made a magnet, and it is filled with magnetic substance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressurized hood sealing device in a sintering facility and a sealing method therefor.

[0002]

2. Description of the Related Art As shown in FIG.
From above, the upper part of the raw material packed bed is ignited by an ignition furnace 8, sucked downward by an exhaust fan 12 through a wind box group 10 and an exhaust duct 11, and There is a pressure sintering method in which a gas is blown from the pressurized hood 3 to which the pushing fan 6 is connected to the upper part of the raw material filling layer, and the sintering pallet 1 is moved in the direction A to sequentially fire from the upper layer to the lower layer.

In such a pressure sintering method, for example, in the initial stage of sintering, the suction pressure of a wind box is reduced to -500 mmAq.
By lowering the moving speed from the upper layer to the lower layer of the sintering zone and making the high-temperature holding time longer than before, the yield and quality of the upper part of the raw material packed layer can be improved. Further, after the middle stage of sintering, for example, air is inserted at 2000 mmAq from the upper part of the raw material packed layer by the pushing fan 6, and suction is performed at -1000 mmAq from below,
By setting the differential pressure of the raw material packed layer to 3000 mmAq, the density of the passing gas is increased, the sintering combustion speed is increased, the heat transfer speed is increased, and the moving speed of the combustion melting zone can be increased. Further, by increasing the cooling rate by increasing the gas flow rate, the thickness of the combustion melting zone in the raw material packed bed is reduced, the ventilation resistance of the combustion melting zone is reduced, and the moving speed of the combustion melting zone can be increased. As a result, the production rate of the sintering machine can be significantly improved in the pressure sintering method.

[0004] However, in the pressure sintering method, it is extremely difficult to seal the pressure hood 3 and the raw material filling layer, and there is hardly any practical example. In particular, when covering the entire sintered pallet 1,
Alternatively, when sealing is performed using a part of the sintered pallet 1, the pallet group swings up, down, left and right, and it is necessary to design in consideration of the influence of thermal expansion and the like when passing through the ignition furnace 8 and firing. This is because there is no sufficient sealing technology.

Japanese Utility Model Publication No. 58-177797 discloses that
"It can be sealed by placing a material having appropriate elasticity on the skirt portion of the fixed hood and sliding it on the upper surface of the sintered ore." However, there is no durable elastic body that can seal even when the skirt is in sliding contact with the sinter on the moving pallet that has irregularities.

[0006] Japanese Utility Model Publication No. Sho 61-141700 discloses that "the seal piece moves while following the vertical movement of the upper surface of the sintered ore, and the seal body expands and contracts following the vertical movement of the seal piece. To seal the outer periphery of the hood. " However, this makes it difficult to seal the corners in the pallet moving direction and the width direction.

Further, as shown in FIG. 8, the lower end of the skirt portion 4 of the pressurized hood 3 may have a direct labyrinth structure. However, since the pressure loss of the direct labyrinth structure is small, air leaking from the side wall of the pallet is considered. Flow rate increases,
An increase in running cost or a decrease in internal pressure occurs, and the operation of pressure sintering becomes difficult. In order to reduce the amount of leakage, it is necessary to increase the number of labyrinths, and there are a problem in space in the width direction, a problem in quality variation due to formation of a pressure distribution, and the like.

[0008]

The above prior art is a mechanism in which sliding occurs between a seal piece and a sintered ore or a seal piece. A normal sintering machine operates continuously for 24 hours, and it is difficult to obtain a sufficient seal piece because the wear of the seal piece is very severe. On the other hand, a sufficient pressure loss could not be obtained by the sealing method in which sliding does not occur. Therefore, development of a sealing technique that does not cause a problem even if sliding occurs has been desired.

Accordingly, the present invention provides a pressurized hood seal device in a sintering facility capable of performing a pressurized sintering method which does not require a seal piece, can obtain a sufficient pressure loss, and can inject gas. It is intended to provide a sealing method.

[0010]

Means for Solving the Problems The present invention provides the following (1)-
It is as (3).

(1) In a sealing device for a pressurized hood provided on a sintering pallet of a downward suction type sintering machine, a lower end of a skirt portion of the pressurized hood has a comb-shaped labyrinth structure in a width direction, and is mounted on a pallet truck. A pressurized hood sealing device in a sintering facility, wherein a plate is installed at a position facing between the labyrinth portions of the pressurized hood to form a staggered labyrinth structure.

(2) The pressurized hood in the sintering facility according to (1), wherein a magnet is provided in the comb-shaped labyrinth and a magnetic material is filled between the comb-shaped labyrinths. Sealing device.

(3) Sealing the lower end of the skirt portion of the pressurized hood and the surface layer of the material-filled layer in a non-contact manner while applying pressure by using the pressurized hood sealing device of (1) or (2). A method for sealing a pressurized hood in a sintering facility.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

As shown in FIGS. 1 to 6, the widthwise lower end of the skirt portion 4 of the pressure hood 3 has a comb-shaped labyrinth structure. By placing the plate 13 at the position where the pressure hood 3 is formed, the widthwise side surface of the pressure hood 3 has a staggered labyrinth structure. Since the surface of the raw material packed layer 2 has irregularities and undulations, the lower end of the pressurized hood cannot be brought into contact with the surface of the packed layer 2 so that a gap is generated, and the pressure inside the pressurized hood 3 is higher than the outside air. Pressurized hood 3
Flow occurred from the gap between the surface of the filler layer 2 and the filler layer 2. In the present invention, since the structure is such that the flow is blocked as compared with the direct labyrinth structure as shown in FIG. 8, the pressure loss is increased, suction is also performed from the lower part, and the leakage flow rate from the pallet side wall is reduced. As a result, the pressure sintering operation becomes stable.

In the example shown in FIG.
4, the inside of the raw material-filled layer 2 has a gas flow and the pressure in the width direction is uniform. Since the main purpose of the plate 13 is to block the flow, the diameter of the plate hole 14 can be selected from a wide range of 10 to 1000 mm and 10 to 90% of the area of the plate 13 as necessary.

Since the entrance side and the exit side of the pressurized hood 3 have a gap with the plate 13 as shown in FIG. 2, leakage from the gap occurs. However, as shown in FIG. 3, it is possible to obtain a necessary pressure loss by increasing the number of direct-flow labyrinths on the entrance side and the exit side of the pressurized hood 3. Even if
A structure as shown in FIG. 5 can be obtained without occurrence of variation in sintering quality and a space problem.

As shown in FIGS. 4 and 6, a part of the lower end of the comb-shaped labyrinth structure on the side surface of the pressurized hood 3 is made to be a magnet 15, and a magnetic substance 16 is adhered, so that the fluid flowing between the labyrinths is further increased. It is possible to reduce the length and the number of labyrinths on the side surface. Examples of the magnetic material 16 include powder such as iron powder and sintered ore and liquid such as magnetic fluid.

[0019]

According to the present invention, the pressure loss of the labyrinth structure increases, and the amount of leakage between the pressurized hood and the surface layer of the raw material filling layer can be reduced to an allowable value or less. Stable operation is possible, and variations in quality can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view in the width direction showing an embodiment of a pressurized hood seal device of the present invention.

FIG. 2 is a widthwise cross-sectional view of an inlet side and an outlet side showing an embodiment of the pressurized hood seal device of the present invention.

FIG. 3 is a sectional view in the traveling direction showing an embodiment of the pressurized hood seal device of the present invention.

FIG. 4 is a cross-sectional view in the width direction of an end showing an embodiment of the pressurized hood seal device of the present invention.

FIG. 5 is a bottom view of the pressurized hood showing an embodiment of the pressurized hood seal device of the present invention.

FIG. 6 is a bottom view of the pressurized hood showing an embodiment of the pressurized hood seal device of the present invention.

FIG. 7 is a view showing a conventional pressure sintering method.

FIG. 8 is a cross-sectional view in the width direction showing an example of a conventional pressurized hood sealing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sintered pallet 2 Raw material filling layer 3 Pressurized hood 4 Skirt part 5 Air blower 6 Push-in fan 7 Raw material tank 8 Ignition furnace 9 Rotating body 10 Window box group 11 Exhaust duct 12 Exhaust fan 13 Plate 14 Plate hole 15 Magnet 16 Magnetic body

Claims (3)

[Claims] In a pressure hood sealing device provided on a sintering pallet of a downward suction type sintering machine, a widthwise shape of a lower end of a skirt portion of the pressure hood has a comb-shaped labyrinth structure, and the hood is formed on a pallet truck. A pressurized hood sealing device in a sintering facility, wherein a plate is installed at a position facing between the labyrinths of the pressurized hood to form a staggered labyrinth structure. 2. The pressurized hood seal in a sintering facility according to claim 1, wherein a magnet is provided in the comb-shaped labyrinth and a magnetic material is filled between the comb-shaped labyrinths. apparatus. 3. The pressurized hood sealing device according to claim 1 or 2, wherein the lower end of the skirt portion of the pressurized hood and the surface layer of the material-filled layer are sealed in a non-contact manner while being pressurized. To seal the pressurized hood in the sintering equipment.