JPH0693342A - Device for sealing gas jet chamber - Google Patents

Abstract

PURPOSE:To improve the heating efficiency of a heater for preventing the thermal crown of a hearth roll and to improve the energy saving and the yield by restricting strip surface cooling gas flow and circulating flow accompanied with this flow developed along the surface of the passed strip between a separated hearth roll chamber and cooling chamber. CONSTITUTION:The roll chamber 13 and the cooling chamber 12a separately formed in a cooling zone are communicated through a strip passage 19 and reverse flow gas jet nozzles 7 for jetting the reverse flow gas E, reversely flowed to the strip surface gas flow D developed by kinetic energy of the cooling gas B are arranged so as to face to both surfaces of the passed strip A at the upper part of the cooling gas chamber 11. Further, this device has the constitution forming a space 8 in the cooling chamber 12a above the reverse flow gas jet nozzle 7 to the strip layer flow leaked from this reverse flow gas to develop exhaust gas flow by the negative pressure of side part exhaust gas from a gas exhaust hole 16. Further, seal rolls 9 are arranged above the space 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to heating or cooling by spraying a gas from a gas injection device onto at least one surface of a thin metal plate that is passed at high speed through a feed roll. Unless the air flow generated along the surface of the metal plate (hereinafter referred to as the plate surface air flow) is restricted to the inside of the feed roll chamber that is separated from the heating or cooling chamber that houses the gas injection device. The present invention relates to a sealing device for a gas jet chamber that does not work.

[0002]

2. Description of the Related Art Recently, in order to improve the press workability of the secondary metal processing industry such as the automobile industry, a metal plate made of, for example, low carbon steel is formed into a series of metal strips by welding. It has been proposed and implemented to obtain the above-mentioned ductility, deep drawability and aging property by recrystallizing annealing a metal strip by a continuous annealing treatment. On the other hand, in order to industrially perform such continuous annealing treatment of a metal strip, a continuous annealing facility constructed by connecting vertical furnaces in series as shown in FIG. 3 is widely adopted. According to this continuous annealing equipment,
After the metal zone (strip) A preheated in the extratropical zone 1 is subjected to predetermined recrystallization in the heating zone 2 or the soaking zone 3,
A predetermined cooling process is performed in the cooling zone 5 and the second cooling zone 6.

By the way, in the first cooling zone 5 and the second cooling zone 6, the strip A is passed up and down by a fixed hearth roll 10. Further, the hearth roll 10 is separated into individual hearth roll chambers 13 with respect to cooling chambers 12a and 12b in which a cooling gas injection device including a gas jet chamber and a gas jet nozzle, which will be described later, are installed. In the cooling chamber, as shown in FIG. 9, the cooling gas B is fed into the gas jet chamber 14, and the cooling gas B is fed from the gas jet nozzle 15 installed opposite to both surfaces of the strip A through which the cooling gas B is passed. The cooling gas B is sprayed on both surfaces, and the heat of the strip A is taken away to perform cooling. Each cooling gas injection device composed of the gas jet chamber 14 and the gas jet nozzle 15 forms some individual cooling gas chamber chambers 11 in the cooling chambers 12a and 12b. Further, in the cooling chambers 12a and 12b, as shown in FIG.
Sides are exhausted from the exhaust ports 16 provided at substantially the center of each cooling gas chamber 11 on both sides in the width direction. The gas jet nozzle 15 is a strip A.
The slit type is used in which the cooling gas B is uniformly sprayed over the entire width direction.

On the other hand, the heating gas in the heating zone 2 is introduced into the hearth roll chamber 13 to heat the hearth roll chamber 13, and a heater 17 using an electric heater is substantially opposed to the longitudinal end portion of the hearth roll 10. It is installed to do. As is known, in the cooling zone, the strip has a higher temperature than the hearth roll, so that there occurs a temperature difference in which the longitudinal central portion of the roll in contact with the strip has a higher temperature than the longitudinal end portion. As a result, a so-called thermal crown is generated in which the central portion of the roll in the longitudinal direction expands from the end portion in the longitudinal direction, which causes buckling called a cooling buckle. Therefore, the heater 17 heats the end portion of the hearth roll 10 in the longitudinal direction to reduce the relative temperature difference between the roll center and the edge portion to reduce the thermal crown amount.

Considering the heating efficiency of the hearth roll 10 by the heater 17, the cooling chambers 12a, 12b.
And it becomes necessary to separate the atmosphere. Therefore, as described in Japanese Patent Application Laid-Open No. 60-141834 previously proposed by the applicant, the hearth roll chamber 13 and the cooling chambers 12a and 12b are separately provided in at least the first cooling zone 5 of the continuous annealing equipment. Of the cooling chambers 12a and 12b in the hearth roll chamber 13 and the seal rolls 18 are provided on both surfaces of the strip A.
Cooling gas B in 2a and 12b is prevented from flowing into the hearth roll chamber 13.

[0006]

When the air flow in the cooling chamber is considered in detail, the cooling gas B is uniformly ejected from the slit type gas jet nozzle 15 over the entire width direction of the strip A, so that the cooling gas B is discharged. With the kinetic energy of and / or the passage of strip A,
A plate surface flow of the cooling gas B is generated in the longitudinal direction of the strip along the surface of the strip close to the center in the width direction. In addition, if this plate surface airflow is a positive airflow, a negative airflow that is directed in the direction opposite to the plate surface airflow is generated outside the widthwise ends of the strip. As a result, on the inlet side and the outlet side of each cooling gas chamber chamber 11, as shown in FIG. 10, a circulating flow C is generated in the positive direction at the widthwise central portion of the strip A and in the negative direction at the outer sides of the strip widthwise end portions. Will be done.

In the first cooling zone 5 in the conventional continuous annealing equipment, the cooling chambers 12a and 12b and the hearth roll chamber 13 are separated as described above, and the seal roll 18 is installed in the hearth roll chamber 13. Although the gas jet chamber is sealed but the actual seal roll 18 is not in contact with the strip, the circulating flow C is
It will be folded back near.

Therefore, the circulating gas C causes the cooling gas B in the cooling gas chamber chamber 11 to flow into the vicinity of the hearth roll 10 and removes the heat in the vicinity of the hearth roll 10 heated by the heater 17. The heating efficiency of the heater 17 is extremely reduced. In order to perform heating so as to limit the thermal crown of the hearth roll 10 in such a low heating efficiency state, the heater 17
The heating capacity of the heating heater per unit area of the heater 17 to be attached to the inner wall of the furnace is predetermined by the wall specifications in the actual problem. When the heating heater 17 is mounted, the wall area must be increased, which causes a problem that the inner area and the capacity of the hearth roll chamber 13 must be extremely large.

Moreover, cooling chambers 12a and 12b between the cooling gas chamber chamber 11 and the hearth roll chamber 13 are provided.
Since there is no space inside, even if a negative pressure is generated by the side exhaust, the circulation flow C is not affected by the negative pressure and is always generated without being disturbed.
In order to solve these problems, for example, the gas jet nozzle at the top of the cooling gas injection device is closed, a preventive plate that prevents circulating flow to both upper sides of the cooling gas injection device is installed, and the seal roll is installed. It is conceivable to install a circulating windbreak plate. However, even if the uppermost gas jet nozzle of the cooling gas injection device is closed, the circulating flow is generated by the kinetic energy of the cooling gas injected from the gas jet nozzle. Even if the gas jet nozzle is closed, the generation of the circulating flow itself cannot be suppressed, and the effect is small. Further, even if the circulating flow prevention plate is installed, there is no escape for the circulating flow itself, so there is almost no effect. In addition, providing a windshield along with the seal roll causes a structural problem.

On the other hand, Japanese Patent Application Laid-Open No. Hei 2 (1994), which the applicant of the present invention has previously proposed
It may be effective to provide a backflow nozzle described in Japanese Patent No. 2824231 as a gas jet chamber sealing device. The backflow nozzle forms a slit-shaped strip passage between the hearth roll chamber and the cooling chamber,
A backflow gas jet that is parallel to the strip width direction and has a velocity component from the hearth roll chamber to the cooling chamber is formed in the strip passage on the surface of the strip. This backflow gas jet can suppress the plate surface airflow by its own kinetic energy. But,
Since the residual portion of the plate surface air flow that cannot be suppressed even by the backflow gas jet flows directly into the hearth roll chamber, the effect of suppressing the circulation flow is limited.

On the other hand, in the case of heating a metal plate having a low temperature through which a heated gas having a higher temperature is blown to heat the metal plate, the opposite phenomenon occurs, but the problem of energy saving or heat is generated. The occurrence of buckling should be similarly resolved. The present invention has been developed in view of these problems, for example, restricting the inflow of the circulation flow into the hearth roll chamber in the cooling device for the thin metal plate to enhance the heating efficiency of the heater and save energy. It is an object of the present invention to provide a gas jet chamber sealing device capable of preventing buckling of strips and improving yield while achieving the above.

[0012]

According to a first aspect of the present invention, there is provided a sealing device for a gas jet chamber in which at least one surface of a thin metal plate which is passed through a feeding roll is provided with a gas from a gas injection device. To heat or cool the metal plate, separate each of the feed roll and the gas injection device into a roll chamber and a heating or cooling chamber, and the gas sprayed onto the thin metal plate is In a heating or cooling device for a thin metal plate that needs to be restricted from flowing into the roll chamber by an air flow generated along the surface of the metal plate, facing the air flow generated along the surface of the metal plate. Is installed opposite to at least one surface of a thin metal plate through which a backflow gas injection device for injecting a backflow gas in a direction is placed in a heating or cooling chamber outside the backflow gas injection device with respect to the gas injection device. Escape the jet gas In which it characterized in that a space Sutame.

According to a second aspect of the present invention, in a gas jet chamber sealing device, a sealing device is provided near a roll chamber side of the space, at a position facing at least one surface of a thin metal plate to be threaded. It is characterized in that a roll is provided.

[0014]

In the gas jet chamber sealing device of the present invention, the backflow gas is jetted from the backflow gas jetting device, which is installed so as to face the surface of the thin metal plate to be passed, in the direction opposite to the plate surface airflow. As a result, the plate surface airflow generated by the kinetic energy of the jet gas can be suppressed by the kinetic energy of the backflow gas, and thus the circulating flow generated around the strip can be suppressed. Further, in a space provided inside the heating or cooling chamber outside the backflow gas injection device with respect to the gas injection device, for example, to the side of the cooling chamber with respect to the plate surface air flow that cannot be avoided only by the backflow gas. A negative pressure due to exhaust causes an exhaust air flow, whereby it is possible to exhaust the cooling gas that is about to flow into the roll chamber side due to the unavoidable plate surface air flow, so that it is substantially introduced into the roll chamber. It is possible to significantly reduce the inflow of the cooling gas, suppress the carry-out of heat in the roll chamber, and improve the heating efficiency of the heater.

[0015]

EXAMPLE FIG. 3 shows an example of continuous annealing equipment for strips made of ultra-low carbon steel having a cooling device for a thin metal plate provided with a sealing device for a gas jet chamber according to the present invention. In the figure, the ultra-low carbon steel strip A is an unillustrated inlet side equipment having a coil rewinding machine, a welding machine, a washing machine, a preheating zone 1, a heating zone 2, a soaking zone 3, a first cooling zone 5,
The second cooling zone 6, the shearing machine, the winding machine, and the like, which are not shown, are passed through the outlet side equipment in this order.

The heating zone 2 heats the strip A continuously fed from the inlet side equipment and preheated in the preheat zone 1 to a temperature higher than the recrystallization temperature. Specifically, the temperature in the furnace is 850. ~ 1000 ℃ temperature of strip A 700 ~
Heat the strip to 950 ° C. The heated strip A is maintained at the recrystallization temperature or higher for the required time in the soaking zone 3 to develop a {1,1,1} texture advantageous for deep drawability.

Strip A sent from the soaking zone 3
Is fed to the first cooling zone 5. In the first cooling zone 5, the strip A heated above the recrystallization temperature is rapidly cooled at a cooling rate of 20 ° C./sec. Or higher until the steel sheet temperature reaches 600 ° C. or lower, preferably about 500 to 400 ° C. In the first cooling zone 5, the flow rate, flow rate, cooling roll temperature, wrapping angle, etc. of the cooling gas blown to the strip conveyed in the cooling zone are controlled so that this cooling condition can be achieved.

In the first cooling zone 5, the strip A is first moved up in the first cooling chamber 12a via the hearth roll 10 and is conveyed substantially horizontally in the hearth roll chamber 13 and then is passed through the hearth roll 10. The second cooling chamber 12b is passed through so as to descend. The cooling chambers 12a and 12b
A cooling gas chamber chamber 11 composed of a gas jet chamber, a gas jet nozzle, and the like is provided inside. Further, the hearth roll chamber 13 includes the cooling chambers 12a,
12b are separated from each other and are connected only via a passage 19 through which the strip A passes. In each of the cooling chambers 12a and 12b, as in the conventional case, as shown in FIG. 2, the cooling gas B is fed into the gas jet chamber and is installed so as to face both surfaces of the strip A to be passed therethrough. The cooling gas B is blown onto both surfaces from the gas jet nozzle 15 so that the cooling gas B takes away the heat of the strip A to perform cooling. Further, in order to balance the cooling gas B delivered in the cooling chambers 12a and 12b, as shown in FIG. 1, the exhaust gas installed in the substantially central portion of each cooling gas chamber chamber 11 on both sides in the width direction of the strip A. Side exhaust is performed from the mouth 16. The gas jet nozzle 1
5 is a slit type in which the cooling gas B is sprayed uniformly over the entire width direction of the strip 15 as in the conventional case. Further, by using this slit type gas jet nozzle 15, the plate surface air flow D along both surfaces near the center in the width direction of the strip, which uses the kinetic energy of the cooling gas B as a driving force, is shown in FIG.
As shown in FIG. 3, the cooling gas chambers 11 are generated from the openings of the cooling gas chambers 11 toward the outside in the longitudinal direction of the strip.

On the other hand, in the hearth roll chamber 13, heating heaters 17 using a heating gas inflow system or an electric heater in the heating zone 2 are installed so as to substantially oppose both ends in the longitudinal direction of the hearth roll 10. ing. This heater 1
As described above, 7 is for reducing the thermal crown generated when the strip A having a temperature higher than that of the hearth roll 10 comes into contact with the hearth roll 10, and the cooling gas B from the cooling chambers 12a and 12b to be described later. The heating capacity is set according to the inflow amount of.

When the plate surface airflow flows into the hearth roll chamber from each of the cooling chambers, a circulating flow of the cooling gas is generated between the cooling chamber and the hearth roll chamber, and the circulation of the cooling gas robs the heat amount in the hearth roll chamber. As a result, the heating efficiency of the heating heater is reduced, and as a result, the heating capacity of the heating heater must be increased, and the heating energy applied is wasted. From these points, the inflow of the cooling gas into the hearth roll chamber along with the plate surface air flow must be suppressed as much as possible.

Therefore, in the gas jet chamber sealing device of the present invention, the backflow gas jet nozzle 7 is installed opposite to both surfaces of the strip A through which the backflow gas jet nozzle 7 is passed. The backflow gas jet nozzle 7 of this embodiment is specifically connected to the gas jet chamber 14 as clearly shown in FIG. 2, and the cooling gas in the gas jet chamber 14 is spread over substantially the entire width direction of the strip A. B is injected as a backflow gas E toward the gas jet nozzle 15 at the uppermost lower part of each cooling gas chamber chamber 11. The backflow gas E jetted from the backflow gas jet nozzle 7 is sprayed relatively in the opposite direction to the plate surface air flow as shown in FIG. 1, and therefore, the cooling is performed by the kinetic energy of the backflow gas E. Plate surface air flow D generated by kinetic energy of gas B
Can be suppressed, and thereby the circulating flow generated around the strip can be suppressed.

Further, in the gas jet chamber sealing device of the present invention, the space 8 is formed in the cooling chamber 12 above and below the backflow gas jet nozzle 15. This space 8 causes an exhaust gas flow F by a negative pressure due to the side exhaust to the plate surface air flow (D) that could not be avoided only by the kinetic energy of the backflow gas E, and thereby the unavoidable plate surface. This is for exhausting the cooling gas B which is about to flow into the hearth roll chamber 13 side with the air flow (D). The size of the space 8 depends on the flow velocity and flow rate of the discharge gas, but is preferably about 300 to 1000 mm in the length of X in FIG.

Further, in this embodiment, as shown in FIGS. 1 and 2, both surfaces of the strip A on the cooling chamber 12 side in the hearth roll 13 and both strips A on the hearth roll chamber 13 side in each cooling chamber 12 are shown. Seal rolls 18 and 9 are arranged on the surface so as to face each other. By disposing the seal rolls 18 and 9 in this manner, the plate surface air flow D, which cannot be avoided by the backflow gas E, is separated from the surface of the strip A,
The laminar flow energy along the strip surface of the plate surface airflow D is dispersed to cause stagnation, and thereby the effect of improving the exhaust efficiency of the cooling gas by the exhaust airflow of the side exhaust is exerted.

The strip A delivered from the first cooling zone 5 is then delivered to the second cooling zone 6. In the second cooling zone 6, gas cooling is performed up to a steel plate temperature of about 250 to 200 ° C. In this way, an extremely low carbon cold-rolled steel sheet for press forming can be finally obtained in which solid solution C exists only in the surface layer portion. Next, the plate surface airflow of the cooling gas in the first cooling zone is analyzed, the inflow amount of the cooling gas into the hearth roll chamber is calculated, the heating capacity of the heater is set, and the set value is considered.

First, as described above, in the hearth roll chamber of the cooling zone, the temperature drop between the central portion in the longitudinal direction of the hearth roll (hereinafter referred to as "roll center") and the end portion in the longitudinal direction of the hearth roll (hereinafter referred to as "roll edge") ( It is considered that the cause of (roll center-roll edge temperature difference) is due to the cooling by the circulating flow of the cooling gas flowing into the hearth roll chamber, so the mechanism of the cooling gas flow and the method of determining the amount of flow into the hearth roll chamber are clarified. To

FIG. 4 shows the cooling gas flow velocity vector on the strip surface measured and analyzed. As is clear from the figure, for example, an upward (positive) gas flow velocity vector is generated in the central portion in the width direction of the chamber upper end opening, and as a result, the gas flow vector is directed to the outside, that is, in the width direction both end portions of the chamber upper end opening, downward A (negative) gas velocity vector is generated. This means that, as shown in FIG. 5, a plate surface airflow D is generated on the surface of the strip A so as to generate a positive circulation flow C at the widthwise center of the strip A and a negative circulation flow C at both widthwise outer sides thereof. means. Considering the gas flow velocity vector and the driving force of the plate surface air flow, the gas jet nozzle 15 used is a slit type that injects the cooling gas B over the entire width direction of the strip A, and therefore the gas jet nozzle 15 is used. It can be seen that there is no escape area for the cooling gas B discharged from the central part of the above, and it is generated by the kinetic energy of the cooling gas B injected from the central part.

A gas flow velocity distribution from the chamber opening is obtained based on the gas flow velocity vector calculated as described above, and a positive gas flow velocity, that is, the plate surface air flow velocity is integrated by the area of the blowout to obtain a unit time. The amount of inflow into the hearth roll chamber side is obtained. And calculate the energy of the backflow gas for suppressing the plate surface airflow velocity and the inflow amount,
Then, the flow velocity and flow rate of the backflow gas E were calculated based on the capability of the backflow gas jet nozzle. Of course, in this embodiment, since the backflow gas jet nozzle is communicated with the cooling gas chamber, the sum of the kinetic energy calculated from the flow velocity and the flow rate of the backflow gas jet and the total kinetic energy of the cooling gas jet is within the gas jet chamber. Although it is equal to the kinetic energy, it goes without saying that a backflow gas pressurizing device or the like may be added if necessary.

Next, FIG. 6 shows the correlation between the discharge velocity of the cooling gas and the flow rate of the cooling gas entering the roll chamber according to this embodiment.
As is clear from the figure, the design cooling gas inflow rate of the present embodiment shown by the solid line in the figure is larger than the cooling gas inflow rate into the conventional roll chamber shown by the dashed line in the figure. It can be seen that the discharge flow velocity of the cooling gas is greatly reduced, and the suppression of the plate surface air flow and the accompanying circulation flow is greatly promoted. In the figure, the flow rate of the gas entering the hearth roll chamber could be reduced to about 1/3 as compared with the conventional method without changing the cooling capacity. Further, the actual measurement value shown in the figure is substantially equal to the design cooling gas inflow rate.

FIG. 7 shows the effect of reducing the heating heater capacity according to this embodiment. As is clear from the figure, for example, the heating amount of the heater required to bring the temperature difference between the roll center and the roll edge to 150 ° C. can be reduced to 1/3 of the conventional amount. Therefore, the discharge flow velocity of the cooling gas is 76 m / s as the calculated design value, and the flow rate of the cooling gas entering the roll chamber is 2200.
When the Nm ³ / hr was set as the gas jet cooling capacity limit, this was applied to the characteristic diagram of the flow rate of the cooling gas entering the roll chamber and the roll center-roll edge temperature difference, as shown in FIG.
Is. In the figure, the roll center-roll edge temperature difference of about 70 ° C. is set as the buckling generation limit, and the range surrounded by the gas jet cooling capacity limit is set as the operating range. As is apparent from the figure, in the present embodiment, it is understood that the operating range can be sufficiently achieved even when the heating heater is used at a load factor of 60%. As a result, the trouble due to the cooling buckle, which occurred in the conventional method 2 to 3 times / month, did not occur at all due to the installation of the seal device for the gas jet chamber of this embodiment.

In this embodiment, a circulating flow is generated on both surfaces of the metal plate to be passed along with the plate surface air flow, and in order to suppress this, a counterflow gas injection device is provided facing both surfaces of the metal plate. Although detailed description has been made on the case of installing, for example, as a result of spraying the cooling gas on either surface of the metal plate to be passed,
When a plate-like airflow that generates a circulating flow is generated only on the surface, the backflow gas injection device may be installed opposite to the surface only. Further, the specific number of nozzles of this backflow gas injection device may be selected as needed depending on how many nozzles are installed on each surface of the metal plate, and is not particularly limited.

In this embodiment, the backflow gas injection device for preventing the cooling gas from flowing into the hearth roll chamber above from the cooling gas injection device has been described in detail. Regardless of the direction of inflow accompanying the plate surface airflow, the point is to install a counterflow gas injection device so as to inject the counterflow gas that opposes the plate surface airflow, and further to the cooling gas injection device. It suffices to form a space for generating an exhaust gas flow on the outside of the injection device, and it is possible to deploy the space in the same manner regardless of whether the space is downward or lateral.

The means for setting the injection velocity and flow rate of the backflow gas from the backflow gas injection apparatus and the capacity of the space are not limited to those described above, and may be appropriately selected according to the specifications of the cooling device to be deployed. You can select it. Further, in the present embodiment, in particular, only the case of continuously annealing a strip made of ultra-low carbon steel has been described in detail, but in particular, a continuous annealing facility capable of carburizing treatment in the preceding step of the cooling step, a cooling gas roll chamber It is also possible to develop heat treatment equipment for other metal plates that wants to suppress the intrusion to the side.

Further, in this embodiment, only the sealing device for the gas jet chamber in the cooling device for the metal plate which uses the cooling gas as the jet gas has been described in detail, but in the present invention, the metal plate which uses the heating gas as the jet gas. It is possible to develop the same in the above heating device, and in that case, the balance of the thermal energy should be considered to be completely opposite.

[0034]

As described above, according to the gas jet chamber sealing device of the present invention, the backflow gas is jetted from the backflow gas injection device in the direction opposite to the airflow on the plate surface, and the airflow on the plate surface is converted into the backflow gas. In a space that can be suppressed by kinetic energy and is provided outside the backflow gas injection device in a heating or cooling chamber, an exhaust airflow is generated for a plate surface airflow that cannot be avoided only by the backflow gas, and a roll chamber is generated. Since the jet gas that is about to flow into the side can be discharged, conventionally, the circulating flow of the jet gas flowing between the roll chamber and the heating or cooling chamber is significantly reduced, and the heat balance in the roll chamber is suppressed. Therefore, for example, it is possible to improve the heating efficiency of the heater or the cooling efficiency of the cooling cooter provided in the roll chamber, while reducing the required heating or cooling capacity. While reliably prevent buckling of the strip to suppress thermal crown of the hearth rolls, it becomes possible to improve the yield by promoting energy conservation.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an embodiment of a thin metal plate cooling device using a gas jet chamber sealing device of the present invention, and an explanatory diagram of an air flow.

FIG. 2 is a vertical cross-sectional view in the strip width direction of the thin metal plate cooling device of FIG.

FIG. 3 is a schematic configuration diagram showing an example of continuous annealing equipment using a cooling device for a thin metal plate provided with a seal layer of a gas jet chamber of the present invention.

4 is an explanatory view of a cooling gas flow generated at a cooling gas chamber chamber opening in the first cooling zone of the continuous annealing equipment of FIG.

FIG. 5 is a schematic explanatory view in which the cooling gas flow performed in FIG. 4 is spread over the entire cooling gas chamber chamber.

FIG. 6 is an explanatory diagram showing an example of the correlation between the discharge velocity of cooling gas and the flow rate of cooling gas entering the roll chamber by the sealing device for the gas jet chamber of the present embodiment.

FIG. 7 is a view showing a heater for setting a predetermined roll center-roll edge temperature difference by setting a flow rate of the cooling gas entering the roll chamber to a predetermined value by using the gas jet chamber sealing device of the present embodiment. It is explanatory drawing which shows an example of the correlation of input energy.

FIG. 8 is an explanatory diagram of a load ratio of a heater required to achieve an operating range based on the correlation between the flow rate of cooling gas entering the roll chamber and the roll center-roll edge temperature difference obtained in FIG. 6;

FIG. 9 is a vertical cross-sectional view in the strip width direction showing a schematic configuration of a cooling device for a thin metal plate using a conventional sealing device for a gas jet chamber.

10 is an explanatory diagram of a schematic configuration and an air flow in the thin metal plate cooling device of FIG.

[Explanation of symbols]

 1 is pre-tropical zone 2 is heating zone 3 is soaking zone 4 is carburizing zone 5 is first cooling zone 6 is second cooling zone 7 is backflow gas jet nozzle 8 is space 9 is seal roll 10 is hearth roll 11 is cooling gas chamber Chambers 12a and 12b are cooling chambers 13 are hearth roll chambers 14 are gas jet chambers 15 are gas jet nozzles 16 are exhaust ports 17 are heaters 18 are seal rolls A are strips B are cooling gases C are circulation flows D are plate surface air flows E is backflow gas

Claims (2)

[Claims] 1. A feed roll and a gas injection device, wherein gas is blown from at least one surface of a thin metal plate passed through a feed roll to heat or cool the metal plate. And a heating chamber or a cooling chamber are separated from each other, and the gas blown to the thin metal plate is restricted from flowing into the roll chamber by an air flow generated along the surface of the metal plate. In a heating or cooling device for a thin metal plate that requires, at least a thin metal plate that is passed through a backflow gas injection device that injects a backflow gas in a direction opposite to an air flow generated along the surface of the metal plate. A seal for a gas jet chamber, which is installed so as to face one surface and has a space for releasing the jet gas in a heating or cooling chamber outside the backflow gas jet device with respect to the gas jet device. apparatus. 2. The seal roll is arranged at a position near the roll chamber side of the space and at a position facing at least one surface of a thin metal plate to be passed. Gas jet chamber sealing device.