JPH09256069A - Continuous heat treatment furnace using different kinds of atmospheric gases and continuous heat treatment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the flow-in and mixing of a different kind atmospheric gas into a treating chamber by supplying a small quantity of an atmospheric gas an to execute excellent continuous heat treatment using different kinds of atmospheric gases. SOLUTION: Partition walls 2 having plural opening parts 4 for carrying a material 5 to be treated are arranged at boundaries between the treating chambers 3a, 3b respectively filled with mutually different kinds of atmospheric gases to plurally connect the treating chambers 3a, 3b. Supplying ducts 7a, 7a', 7b, 7b' for circulating gas connected to the treating chambers 3a, 3b through circulating gas suction holes, are formed in the partition walls 2 and gas supplying slits 9a, 9a', 9b, 9b' capable of adjusting the flow rate of the circulating gas in the sheet width direction of the material 5 to be treated, are arranged at the side faced to the opening parts 4. At the time of executing the heat treatment by conveying the material 5 to be treated through the opening parts 4, the circulating gas sucked from the treating chambers 3a, 3b is supplied to the material 5 to be treated from the gas supplying slits 9a, 9a', 9b, 9b' facing is both surfaces while it is supplied from one side supplying slits 9a', 9b', alone to the conveying surface where the material 5 to be treated is absent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous atmosphere heat treatment furnace of different atmosphere gas and a continuous heat treatment method for continuously heat-treating a material to be treated by using different atmosphere gases, and more particularly to a component of the different atmosphere gas. The present invention relates to a continuous heat treatment furnace and a continuous heat treatment method of different atmosphere gas in which heat treatments that greatly differ from each other or heat treatments in which the component conditions of the atmosphere gas are severe.

[0002]

2. Description of the Related Art In continuous heat treatment of different atmosphere gas using different atmospheres, a plurality of processing chambers partitioned by partition walls are connected,
A different atmosphere gas, such as an inert gas, a reducing gas, or a cooling gas, is passed through each processing chamber, and the material to be processed such as a metal strip is continuously conveyed through an opening provided in the partition wall to perform annealing treatment or reduction. It is a heat treatment for performing the treatment.

As a conventional processing furnace of this type, there is, for example, a continuous processing apparatus disclosed in Japanese Patent Laid-Open No. 125451/1993, the outline of which is shown in FIG.

In the continuous heat treatment furnace 1, a plurality of processing chambers 3a and 3b partitioned by a partition wall 2 are connected to each other, and each processing chamber 3 is separated from the partition wall 2.
Different atmosphere gases such as an inert gas, a reducing gas, and a cooling gas are passed through a and 3b, respectively, and the material 5 to be treated such as a metal band is continuously conveyed through the opening 4 provided in the partition wall 2. Perform processing.

The partition wall 2 is divided into upper and lower three chambers in the conveying direction 6 of the material to be processed, and supply ducts 7a, 7a ', 7b, 7b' for circulating gas are provided in the respective chambers on the processing chambers 3a, 3b side.
However, exhaust ducts 8 and 8'are formed in the central part, and gas supply slits 9a, 9a ', 9b and 9 are provided on the sides of the circulating gas supply ducts 7a, 7a', 7b and 7b 'facing the opening 4.
b ', and mixed gas suction holes 10, 10' are provided on the sides of the exhaust ducts 8, 8'facing the opening 4, respectively.

Each supply duct 7a, 7a ', 7b, 7b'
Through the blowers 11a and 11b.
circulation ducts 12a, 12b for circulating the atmospheric gas of b
And supply pipes 13a, 13 for replenishing the reduced atmospheric gas
b is connected, and an exhaust pipe 15 for exhausting gas in the exhaust ducts 8 and 8 ′ is connected to the exhaust ducts 8 and 8 ′ via a blower 14.

When performing heat treatment using the continuous heat treatment furnace 1, the circulating gas is supplied from the supply ducts 7a, 7a ', 7b, 7b'. In this case, a gas cushion 16 for isolating the two processing chambers 3a and 3b is formed at a position where the circulating gas in the opening 4 contacts, but at the same time, a part of the atmospheric gas is mixed at this position. The mixed atmospheric gas is treated through the mixed gas suction holes 10 and 10 ', and is exhausted to the outside of the system through the exhaust ducts 8 and 8'and the exhaust pipe 15 in a timely manner. Prevent them from flowing into the chambers 3a, 3b,
Establish the atmospheric gas conditions in the processing chambers 3a and 3b.

[0008]

However, in the above continuous processing apparatus, when the components of the different atmosphere gases are greatly different, or when the component conditions of the atmosphere gas are severe,
There is a problem that it is difficult to establish the atmospheric gas conditions in the processing chamber, and the exhaust gas amount is large, that is, the expensive atmospheric gas supply amount is required to be large.

In view of the above problems, the present invention provides a continuous heat treatment furnace and a continuous heat treatment method of different atmosphere gas capable of performing excellent treatment by preventing a different atmosphere gas from flowing into and mixing into the processing chamber with a small amount of supply atmosphere gas. The purpose is to provide.

[0010]

SUMMARY OF THE INVENTION The present invention advantageously solves the above-mentioned problems and is based on the difference in the atmospheric flow, in particular, the unsteady flow of the material to be processed in the plate width direction, that is, the presence or absence of the material to be processed. Focusing on the difference in unsteady flow, it is possible to prevent the inflow and mixing of different atmosphere gases into the processing chamber with a small amount of supply atmosphere gas, and to perform excellent processing.

The different atmosphere gas continuous heat treatment furnace of the present invention is as follows.

In a different atmosphere gas continuous heat treatment furnace in which a plurality of processing chambers partitioned by partition walls are connected to each other and the material to be processed is continuously conveyed through an opening provided in the partition walls for processing, Circulation duct through the suction port,
A circulating gas supply duct connected by a blower is formed in the partition wall, and means for adjusting the flow rate of the circulating gas in the plate width direction of the material to be processed is provided on the side facing the opening of the circulating gas supply duct. A continuous heat treatment furnace for different atmosphere gases, characterized by having a gas supply slit.

The means for adjusting the flow rate of the circulating gas in the plate width direction of the material to be processed is a shielding bar having a drive mechanism in the plate width direction of the material to be processed, and the continuous heat treatment of different atmosphere gas is performed. Furnace.

The different gas atmosphere continuous heat treatment, characterized in that the gas supply slit is divided into a plurality of regions in the plate width direction of the material to be treated, and means for adjusting the flow rate of the circulating gas in each divided region is provided. Furnace.

In a heterogeneous atmosphere gas continuous heat treatment furnace in which a plurality of processing chambers partitioned by partition walls are connected and a material to be processed is continuously conveyed through an opening provided in the partition walls to perform processing, the processing chambers and a circulating gas Circulation duct through the suction port,
A circulation gas supply duct connected by a blower is formed in the partition wall, and a gas supply slit is provided on the side facing the opening of the circulation gas supply duct, and both ends of the opening in the plate width direction of the material to be treated. In the continuous heat treatment furnace for different atmosphere gas, a gas reflection plate having a drive mechanism in the plate width direction is arranged.

The method of continuous heat treatment of different atmosphere gases of the present invention is as follows.

In a continuous heat treatment method of different atmosphere gases using two or more kinds of atmosphere gases, a partition having an opening for transporting a material to be processed is provided at the boundary of a processing chamber filled with the different atmosphere gas, and the partition is partitioned by the partition. A plurality of processing chambers are connected to each other, a circulating gas supply duct is formed in the partition wall, and the circulating gas sucked from the processing chamber is covered from a gas supply slit on the side facing the opening of the circulating gas supply duct. A continuous heat treatment method for different atmosphere gases, characterized in that the gas is supplied while adjusting the gas flow rate in the plate width direction.

Circulating gas is supplied to the material to be processed from the gas supply slits facing both sides of the material,
The continuous heat treatment method for different atmosphere gases, characterized in that the circulating gas is supplied only to the gas supply slit facing one surface of the carrying surface to the carrying surface where the material to be treated does not exist.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below.

The inventors of the present invention have paid close attention to the behavior of the gas flow in the furnace of the continuous heat treatment furnace for different atmospheres, and have conducted a detailed investigation. As a result, the conveyance surface where there is no material to be processed in the partition walls, that is, the material to be processed. The non-steady atmosphere flow of the atmospheric gas in the non-existing area (both ends of the material to be processed in the partition wall in the plate width direction) is significantly different from that in the area where the material to be processed is different from that of the different atmospheric gas to the processing chamber. It was found that it had a strong influence on inflow or pollution.

1 to 3 show an example of the continuous heat treatment furnace for different atmosphere gases of the present invention. FIG. 1 is a schematic cross-sectional view of a material to be processed in a conveyance direction in a region where the material to be processed exists. FIG. 2 is a schematic cross-sectional view of the non-existing region of the material to be processed (both ends of the material to be processed in the plate width direction) in the transport direction of the material to be processed. FIG. 3 is a schematic cross-sectional view in the direction perpendicular to the transport direction of the material to be treated at the position of the circulating gas supply duct.

In the continuous heat treatment furnace 1, the processing chambers 3a and 3b partitioned by the partition wall 2 are connected to each other, and one shielding wall 21a and 21b is installed on each side of the partition wall 2 in the conveying direction 6 of the material to be processed. ing. The partition wall 2 is divided into three chambers each in the upper and lower direction in the conveying direction 6 of the material to be treated, and the supply ducts 7a, 7a ', 7b, 7b' for circulating gas are provided in the central chambers in the respective chambers on the processing chambers 3a, 3b side. Exhaust ducts 8 and 8'are respectively formed, gas supply slits 9a, 9a ', 9b and 9b' are provided on the sides of the supply ducts 7a, 7a ', 7b and 7b' facing the opening 4, and the exhaust duct 8 is also provided. , 8'on the side facing the opening 4 are provided with mixed gas suction holes 10, 10 ', respectively. Further, at both ends of the gas supply slits 9a, 9b above the material 5 to be processed, gas supply slit shield bar driving devices 52a, 52a ', 52b, 52b' are connected to the gas supply slit shield bars 51a, 51a ', respectively. , 51b, 51
b'is provided. Each supply duct 7a, 7a ', 7
b and 7b 'are connected to circulation ducts 12a and 12b which circulate the atmospheric gas in the portions 22a and 22b of the processing chambers partitioned by the shielding wall via the blowers 11a and 11b, and the exhaust ducts 8 and 8'. An exhaust pipe 15 for exhausting the gas in the exhaust ducts 8 and 8 ′ is connected to the exhaust pipe 8 via a blower 14. Further, the material 5 to be processed is conveyed through the opening 4. Further, supply pipes 13a 'and 13b' for supplying different atmosphere gases are connected to both outer sides of the shielding walls 21a and 21b.

When performing the treatment in the continuous heat treatment furnace 1,
When supplying the circulating gas from the supply ducts 7a, 7a ′, 7b, 7b ′, the gas supply slit shielding bar 51 is aligned with the plate position (plate width direction) of the material 5 to be processed, as shown in FIG.
a, 51a ′, 51b, 51b ′ are driven by the gas supply slit shield bar driving devices 52a, 52a ′, 52b, 52b ′, and the non-existing region of the processed material 5 (the processed material 5
The gas supply slits at both ends in the plate width direction) are closed.

In the region where the material 5 to be treated is present, as shown in FIG. 1, upper and lower gas supply slits 9a, 9a ', 9b,
Circulating gas is supplied from 9b '. In this case, since the material 5 to be treated is present, the disturbance of the atmosphere flow is relatively small.
Nevertheless, a part of the atmospheric gas mixes at the location where the supply gas contacts the opening 4. A part of this mixed gas forms a complicated circulating gas flow 18 in the portions 22a and 22b of the processing chambers partitioned by the shielding wall, and a part of the mixed gases is the processing chambers 3a and 3b.
Try to flow into. In addition, the gas flow 20 that accompanies the material to be processed 5 and passes through the opening 4 of the partition wall 2 and that accompanies the material to be processed, or the gas flow due to the furnace pressure difference between the front and rear processing chambers 3a and 3b is also generated. Exists. In the continuous heat treatment furnace 1, the mixed gas is mixed gas suction holes 10, 1
It is sucked from 0 ', and exhausted to the outside of the system at appropriate time through the exhaust ducts 8 and 8'and the exhaust pipe 15. Further, shielding walls 21a and 21b are provided, and a different atmosphere gas is supplied to the processing chambers 3a and 3b through supply pipes 13a 'and 13b', and the processing chambers 3a and 3b are each parted with a shielding wall 22a. , 22b in the direction of the processing chambers 3a, 3b through the portions 22a, 22b of the processing chambers in which the mixed atmospheric gas or the different atmospheric gases are separated by the shielding wall. It prevents the gas from flowing into the main body and secures a clean atmosphere gas in the main body of the processing chambers 3a, 3b.

In the non-existing region of the processed material 5 (both ends of the processed material 5 in the plate width direction), the circulating gas is supplied only from the lower gas supply slits 9a 'and 9b' as shown in FIG. The direct collision of the circulating gas from the upper and lower gas supply slits is avoided, and the turbulence of the atmosphere flow becomes equal to the existing region of the material 5 to be treated.

Since the partition wall 2 exhibits the above-described action, the atmospheric gas in the main body of the processing chambers 3a and 3b is not polluted and only the original atmospheric gas is continuously supplied, and the material to be processed 5 is processed.
In addition to ensuring the quality of the gas, it is not necessary to supply a large amount of atmospheric gas in order to ensure the atmospheric density.

The shield walls 21a and 21b do not necessarily have to be installed, and may be determined in consideration of, for example, the strictness of the component conditions of the atmosphere.

In order to prevent the collision of the circulating gas from the upper and lower gas supply slits, it is effective to divide the gas supply slit in the plate width direction of the material to be treated and adjust the flow rate of each circulating gas. Is. Furthermore, it is also effective to provide gas reflection plates that move according to the transport position (plate width direction) of the material to be processed at both ends of the opening in the board width direction of the material to be processed.

The structure of the continuous heat treatment furnace of the present invention is effective for any continuous atmosphere gas continuous heat treatment furnace in which a circulating gas is supplied from a gas supply slit, and may be a vertical furnace or a horizontal furnace.

[0030]

Next, the present invention will be described in more detail with reference to examples.

1 to 3 show a decarburizing and reducing furnace for non-oriented silicon steel sheets as an embodiment of the present invention. The processing chambers 3a and 3b for partitioning the decarburization and reduction processes, which are partitioned by the partition wall 2, are connected to each other, and the shielding walls 21a and 21b are provided on both sides of the partition wall 2 in the transport direction 6.
Is installed. The material 5 to be processed is continuously processed while being conveyed through the partition walls 2 and the openings 4 provided in the shielding walls 21a and 21b. Gas supply slits 9a, 9a ', 9b,
The angle of 9b 'is 60 with respect to the conveying direction 6 of the material to be treated.
And 150 °, and the angles on both sides of the partition wall 2 are 60 ° and 150 ° with respect to the conveyance direction 6 of the material to be treated.
The width of the gas supply slits 9a, 9a ', 9b, 9b' is 6
mm.

Each supply duct 7a, 7a ', 7b, 7b'
Is connected to the circulation ducts 12a and 12b for circulating the atmospheric gas in the portions 22a and 22b of the processing chamber partitioned by the shielding wall via the blowers 11a and 11b, and the exhaust ducts 8 and 8'are connected to the blower 14 respectively. Through the exhaust duct 8, 8 '
A discharge pipe 15 for discharging the gas inside is connected. Also,
A supply pipe 13a 'for supplying a decarburizing atmosphere gas and a supply pipe 13b' for supplying a reducing atmosphere gas are connected to both outer sides of the shielding walls 21a and 21b, respectively.

When the heat treatment is performed in the continuous heat treatment furnace 1, the circulating gas is supplied from the supply ducts 7a, 7a ', 7b, 7b' to the main bodies of the processing chambers 3a, 3b, and a part of the mixed gas of the circulating gas is supplied. It is sucked through the mixed gas suction holes 10 and 10a ', and is discharged to the outside of the system at appropriate time through the exhaust ducts 8 and 8'and the discharge pipe 15. As shown in FIG. 3, the gas supply slit shield bars 51a, 51a ′, 51b, 51b ′ are gas supply slit shield bar driving devices 52a, 52a ′, which match the plate position (plate width direction) of the material 5 to be processed. 52b and 52b 'are driven to drive the gas supply slits 9a above the material 5 to be processed,
Part of 9b, that is, non-existing region of the material 5 to be processed: Both ends are closed. On the other hand, the replenishment gas is supplied to the supply pipes 13a ′, 13
It is supplied to the main body of the processing chambers 3a and 3b from b '. Thus, the upper and lower gas supply slits 9a, 9a ', 9
The direct collision of the circulating gas from b and 9b ′ is avoided, and the turbulence of the atmosphere flow becomes equal to the existing region of the material 5 to be treated,
The processing chamber 3 passes through the processing chambers 22a and 22b in which the mixed atmospheric gas or the different atmospheric gas is partitioned by the shielding wall.
a, 3b are prevented from flowing into the main body, and the processing chamber 3a,
It was possible to secure a clean atmosphere gas in the body of 3b.

FIG. 4 shows another example of the continuous atmosphere gas continuous heat treatment furnace of the present invention.

This continuous heat treatment furnace is also a decarburization and reduction furnace for non-oriented silicon steel sheets. The difference from FIG. 1 is that instead of providing a gas supply slit shielding bar, the circulating gas supply ducts 7a, 7a ′, 7b, 7b ′ are divided in the plate width direction of the material 5 to be processed, and the amount of each circulating gas is different. Gas flow rate control valves 61a to 61g, 61a 'to 61g'
Is the point. Depending on the plate position (plate width direction) of the material 5 to be processed, the flow rate adjusting valves 61a, 61b, 61f, 61g above the non-existing regions (both ends) of the material 5 to be processed are closed, while facing them. The flow rate control valves 61a ′, 61′b, 61f ′, 61g ′ below the material 5 to be processed are
It is opened so that the amount of gas supplied from the gas supply slit per unit length in the furnace width direction is constant.

FIG. 5 shows still another example of the continuous heat treatment furnace for different atmosphere gases of the present invention.

This continuous heat treatment furnace is also a decarburizing and reducing furnace for non-oriented silicon steel sheets. The difference from FIGS. 3 and 4 is that, instead of adjusting the supply gas amount in the plate width direction of the processing target material 5 from the gas supply slit, the gas reflection plate drive devices 72a, 72.
The point is that the gas reflection plates 71a and 71a 'connected to a'are provided. The gas reflection plate driving devices 72a and 72a ′ are driven according to the plate position (plate width direction) of the material to be processed 5 and the gas reflection plates 71a and 71a are formed in the non-existing region of the material to be processed 5.
The presence of a ′ prevents the gases supplied from the upper and lower gas supply slits from directly colliding with each other.

[0038]

According to the present invention, by supplying a small amount of atmospheric gas, inflow and mixing of different atmospheric gases into the processing chamber can be prevented, and the atmospheric gas in the processing chamber can be prevented from being polluted. The quality of the material is secured. Further, it is not necessary to supply a large amount of atmospheric gas, and the operating cost can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a material to be processed in an area where the material to be processed is conveyed in an example of a different atmosphere gas continuous heat treatment furnace of the present invention.

FIG. 2 is a schematic cross-sectional view of a material to be processed in a conveyance direction in a non-existing area of the material to be processed in an example of a continuous heat treatment furnace for different atmosphere gases of the present invention.

FIG. 3 is a schematic cross-sectional view of an example of a different atmosphere gas continuous heat treatment furnace of the present invention in a direction perpendicular to the transport direction of a material to be treated at a position of a circulating gas supply duct.

FIG. 4 is a schematic cross-sectional view of another example of the different atmosphere gas continuous heat treatment furnace of the present invention in a direction perpendicular to the transport direction of the material to be treated at the position of the circulating gas supply duct.

FIG. 5 is a schematic cross-sectional view of yet another example of the different atmosphere gas continuous heat treatment furnace of the present invention in a direction perpendicular to the conveyance direction of the material to be treated at the position of the circulating gas supply duct.

FIG. 6 is a schematic sectional view showing an example of a conventional continuous heat treatment apparatus for different atmosphere gases.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Continuous heat treatment furnace 2 Partition walls 3a, 3b Processing chamber 4 Opening 5 Material to be processed 6 Transport direction of material to be processed 7a, 7a ', 7b, 7b' Circulating gas supply duct 8, 8'Exhaust duct 9a, 9a ', 9b, 9b 'Gas supply slit 10, 10' Mixed gas suction hole 11a, 11b, 14 Blower 12a, 12b Circulation duct 13a, 13b Supply pipe 13a ', 13b' Supply pipe 15 Discharge pipe 16 Gas cushion 17 Near mixed gas suction hole Gas flow 18 Circulating gas flow 18 'Circulating gas flow 19 Non-mixed heterogeneous atmosphere gas flow 20 Gas flow accompanying the material to be treated 21a, 21b Shielding wall 22a, 22b Of the processing chamber partitioned by the shielding wall Part 51a, 51a ', 51b, 51b' Gas supply slit shield bar 52a, 52a ', 52b, 52b' Gas supply slit shield bar drive Location 61a~61g, 61a'~61g 'flow control valve 71a, 71a' gas reflector 72a, 72a 'gas reflector drive

Claims (6)

[Claims] 1. A different atmosphere gas continuous heat treatment furnace in which a plurality of processing chambers partitioned by partition walls are connected to each other and the material to be processed is continuously conveyed through an opening provided in the partition walls to perform processing. Circulation duct through the circulation gas suction port,
A circulating gas supply duct connected by a blower is formed in the partition wall, and means for adjusting the flow rate of the circulating gas in the plate width direction of the material to be processed is provided on the side facing the opening of the circulating gas supply duct. A continuous heat treatment furnace for different atmosphere gases, characterized by having a gas supply slit. 2. The shielding bar having a drive mechanism in the plate width direction of the material to be processed, wherein the means for adjusting the flow rate of the circulating gas in the plate width direction of the material to be processed is a shield bar. Different atmosphere gas continuous heat treatment furnace. 3. The gas supply slit is divided into a plurality of regions in the plate width direction of the material to be treated, and the device has means for adjusting the flow rate of the circulating gas in each of the divided regions. Different atmosphere gas continuous heat treatment furnace. 4. A continuous atmosphere heat treatment furnace of different atmosphere in which a plurality of processing chambers partitioned by partition walls are connected and the material to be processed is continuously transported through an opening provided in the partition walls to perform processing. Circulation duct through the circulation gas suction port,
A circulation gas supply duct connected by a blower is formed in the partition wall, and a gas supply slit is provided on the side facing the opening of the circulation gas supply duct, and both ends of the opening in the plate width direction of the material to be treated. In the continuous heat treatment furnace for different atmosphere gas, a gas reflection plate having a drive mechanism in the plate width direction is arranged. 5. In a continuous heat treatment method of different atmosphere gases using two or more kinds of atmosphere gases, a partition wall having an opening for transporting a material to be processed is provided at the boundary of a processing chamber filled with the different atmosphere gas, and the partition wall is used. A plurality of partitioned processing chambers are connected to each other, a circulating gas supply duct is formed in the partition wall, and a circulating gas sucked from the processing chamber is supplied from a gas supply slit on the side facing the opening of the circulating gas supply duct. A continuous heat treatment method of different atmosphere gas, wherein the gas is supplied while adjusting the gas flow rate in the plate width direction of the material to be treated. 6. A material to be processed is supplied with a circulating gas from gas supply slits facing each of both surfaces thereof, and a carrying surface on which no material to be processed is present is provided on one side of the carrying surface. 6. The continuous heat treatment method for different atmosphere gases according to claim 5, wherein the circulating gas is supplied only from the gas supply slits.