JP2794541B2 - Sealing device for heat treatment furnace using atmosphere gas containing hydrogen gas - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reducing method containing hydrogen gas for performing a heat treatment for annealing or strain-relief annealing a metal strip such as a stainless steel strip without forming an oxide film on its surface. The present invention relates to an improvement in a sealing device provided with a seal pad made of an elastic body and an elastic rotating roll in a heat treatment furnace using an atmospheric gas.

[0002]

2. Description of the Related Art A heat treatment furnace for performing heat treatment for bright annealing or strain relief annealing of a metal strip such as a stainless steel strip without forming an oxide film on the surface thereof has, for example, 75% hydrogen gas and nitrogen A flammable reducing atmosphere gas (hereinafter, may be simply referred to as furnace gas) containing hydrogen gas such as a mixed gas of 25% gas is supplied.

[0003] A device for shutting off the gas inside the furnace from the outside air (hereinafter, sometimes referred to as a seal) is provided at a portion of the heat treatment furnace where the metal bands at the entrance and exit pass. As the device, for example,
As disclosed in Japanese Patent Publication No. 18893, an elastic rotating roll which sandwiches a metal band and rotates at substantially the same speed as the traveling speed of the metal band, and a flexible seal metal having one end fixed to a furnace body. There is introduced a sealing device including a pad such as a felt that is fixed and seals between the elastic rotating rolls (hereinafter referred to as a sealing pad).

A vertical bright annealing furnace for a stainless steel strip will be described below as an example of a conventional heat treatment furnace using an atmosphere gas containing hydrogen gas. FIG. 5 is a structural explanatory view of a general vertical bright annealing furnace for a stainless steel strip. A metal strip S made of a stainless steel strip passes through a sealing device 2 'provided on the inlet side via a deflector roll. After being heated into a furnace body 1 and heated to a predetermined temperature, it is cooled, and when it comes out again, it passes through a sealing device 2 'provided on the outlet side. The flammable furnace gas containing hydrogen gas as described above is constantly injected into the furnace body 1, and the furnace pressure is maintained at a pressure about 10 to 50 mmH ₂ O higher than the outside air. In order to prevent air (oxygen) from entering the body 1 and mixing with the furnace gas, the furnace is operated so as to gradually leak from the sealing devices 2 ', 2' provided at the entrance and exit to the outside air. .

FIG. 6 is an enlarged front view of a conventional sealing device provided on the outlet side, and FIG. 7 is a partial side view of the same. In this conventional sealing device 2 ′, one end of a seal pad 5 ′ made of felt or a felt equivalent is fixed to a side plate 3 a of a furnace wall 3 of a furnace body 1. Seal hardware 4 'made of a thin plate such as stainless steel
The elastic rotating roll 6 'is fixed to the metal band S and the seal pad 5' by the operating force of the piston rod 7a driven by the cylinder of the roll opening / closing mechanism 7 by sticking it to the surface of the roller or using bolts and nuts. And the inside of the furnace body 1 is sealed from the outside air.

[0006] The elastic rotating roll 6 'is pressed against the metal strip S and the seal pad 5' fixed to the surface of the seal fitting 4 'having one end fixed to the side plate 3a of the furnace wall 3 of the furnace body 1. The roll opening / closing mechanism 7 will be briefly described with reference to FIGS. 6 and 7. The lever 7 b is pivotally mounted on a fixed pin 7 c serving as a center of rotation, and has a roll shaft 6 d ′ of an elastic rotating roll 6 ′ at its tip. A bearing 6e 'supporting the elastic rod 6a is attached to the rear end thereof, and the operating force of the piston rod 7a driven by the cylinder is applied to the rear end. At the same time, the furnace body 1 is pressed against the seal pad 4 'fixed to the seal fitting 4' to shut off the inside of the furnace body 1 from the outside air, thereby sealing the gas in the furnace. Since the elastic rotating roll 6 'has a body length longer than that of the metal band S, the elasticity of the elastic rotating roll 6' at both ends in the width direction of the metal band S prevents a gap corresponding to the thickness of the metal band S from being formed. ing.

However, in such a conventional sealing device 2 ', when the cylinder of the roll opening / closing mechanism 7 is driven to apply an operating force to the piston rod 7a, the two elastic rotating rolls 6' cause the metal band passing between them to move. S and the seal pad 5 'fixed to the seal fitting 4' at the same time, the seal fitting 4 'having a spring action of pressing the seal pad 5' against the elastic rotating roll 6 'is provided by the elastic rotating roll. When a method of generating a large frictional force between the seal rotating pad 6 'and the sealing pad 5' is used, since the elastic rotating roll 6 'has a small roll hardness to improve the sealing performance, the elastic rotating roll 6' Not only is the surface damaged or worn by the friction with the seal pad 5 ', but also the surface of the seal pad 5' is fuzzed by the friction with the elastic rotating roll 6 '. Since the fluff adheres to the metal band S and is pressed by rolling in a later step, thereby deteriorating the surface quality of the metal band S, the seal metal 4 'has a very small pressing force due to its spring action as described above. It must be made of a thin plate such as stainless steel, so that the contact pressure between the elastic rotating roll 6 'and the sealing pad 5' is made uniform over the entire length of the elastic rotating roll 6 '. It is very difficult because the pad 5 'does not have a precise dimensional accuracy like a machined product, and the gas in the furnace is removed from the part where the contact pressure between the elastic rotating roll 6' and the seal pad 5 'is low. There was a case where a phenomenon of leaking out more than the part occurred.

Further, since the two elastic rotating rolls 6 'have a small roll hardness in order to improve the sealing property, they are always in contact with the sharp edge portion of the metal band S when pressed against the metal band S passing therethrough. In some cases, the part that is damaged is intensively damaged or worn and has a small diameter, and a phenomenon in which gas in the furnace leaks from the gap between the worn part and the metal strip S more frequently than in other parts may occur.

When the gas in the furnace leaks, the gas in the furnace is a gas containing flammable hydrogen gas, as described above. When a high temperature debris or the like dropped from the metal strip to be heat-treated and dropped into the sealing device 2 ′ and discharged out of the furnace, the mixture with the air near the sealing device 2 ′ may be ignited,
A fire is likely to occur due to a spark caused by static electricity generated in the elastic rotating roll 6 'and the seal pad 5' that are rubbed against each other.

When such a fire occurs, nitrogen gas is injected into the inside of the furnace of the sealing device 2 'or the sealing device 2'
By extinguishing nitrogen gas into the sealing portion by a fire extinguisher attached to the seal, or blowing carbon dioxide gas onto the outer surface of the seal device 2 ', the fire can be extinguished in a relatively short time of about 10 seconds. Then, the seal pad 5 'and the elastic rotating roll 6' constituting the sealing device 2 'are damaged by the fire of the high-temperature hydrogen gas flame, and the elasticity and the sealing property are lost. When the seal pad 5 'is made of a single wool felt, if the wool felt is made to have elasticity, the air permeability becomes better and the sealing property becomes insufficient or unsuitable. Becomes smaller, the surface softness is lost, and the surface of the elastic rotating roll 6 'is scratched or worn by rotating and sliding, and the flexibility to follow the unevenness of the roll surface is increased. It is lost and the sealing performance deteriorates. Further, it is not preferable because fluffing, hair detachment and abrasion easily occur. The fluffing deteriorates the sealing property, and the loosening causes the fibers to adhere to the metal band S and generate indentation defects at the time of rolling the metal band S in the next step. Therefore, the sealing pad 5 'has fluff, hair loss, sealing property, soft surface, flexibility of the pad itself,
From the viewpoint of abrasion resistance and stabilization of quality, wool felts were sometimes used with polyester fiber or acrylic fiber felt adhered to the surface, but these fibers had only a low melting point and softening point. However, as shown in FIG. 8, the critical oxygen index (index of the minimum oxygen volume fraction necessary for the fiber to maintain the combustion) LOI value was small, and combustion was stopped because oxygen was present in the air outside the furnace. Due to its continuous nature, if a fire occurs, even in a very short time of about 10 seconds, it melts and drops onto and adheres to the elastic rotating roll 6 ′, damaging the elastic rotating roll 6 ′ or leaving traces of the metal band S. And the function as a sealing device is reduced or lost.

[0011]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art and is provided at the entrance and exit of a flammable furnace gas section of a heat treatment furnace using an atmosphere gas containing hydrogen gas. The heat resistance between the seal pad and the elastic rotating roll in the sealing device is improved, and even if a short-term fire occurs near the sealing device, the sealing performance does not decrease, and the sealing performance is stable for a long time. It is an object to provide a sealing device that can be secured.

[0012]

Means for Solving the Problems The present inventor has disclosed a seal fitting which is provided at the entrance and exit of a heat treatment furnace using an atmosphere gas containing hydrogen gas as a furnace gas, and one end of which is fixed to a side plate of a furnace wall. And a seal pad made of an elastic body fixed to the surface of the seal metal, and held on furnace walls located on both sides in the width direction of the metal band, and pressed against the seal pad and the metal band to remove furnace gas. In a sealing device comprising an elastic rotating roll for sealing, the surface of the sealing pad has a critical oxygen index (index of a minimum oxygen volume fraction necessary for maintaining the fiber burning) LOI value of 26 or more. The inventor of the present invention has determined that the above-mentioned problems can be solved if the material is made of a satisfactory material.

Hereinafter, a sealing apparatus for a heat treatment furnace using an atmosphere gas containing hydrogen gas according to the present invention will be described in detail with reference to the drawings. FIG. 1 is an enlarged explanatory side view showing one embodiment of the end structure of the elastic rotating roll in the apparatus of the present invention, and FIG. 2 is a view of the vicinity of a seal pad portion made of an elastic body fixed to the surface of a seal fitting in the apparatus of the present invention. FIG. 3 is an enlarged cross-sectional explanatory view showing an embodiment, FIG. 3 is an enlarged cross-sectional explanatory view showing an embodiment in the vicinity of a seal pad portion made of an elastic body fixed to the surface of a seal metal in the device of the present invention, and FIG. It is an expanded sectional explanatory view showing an example of a rotating disk using a bearing arranged between a roll trunk of an elastic rotating roll and furnace walls on both sides.

In the drawings, reference numeral 1 denotes a reducible metal-containing strip S such as a stainless steel strip which contains hydrogen gas for heat treatment for annealing or strain relief annealing without forming an oxide film on its surface. A furnace body of a heat treatment furnace using a flammable atmosphere gas as a furnace gas, wherein a furnace gas is supplied into the furnace body 1 so that 10 to 50 mmH ₂ from outside air is supplied.
The pressure is maintained at a pressure as high as O.

[0015] 2 is provided at the entrance and exit of a heat treatment furnace using an atmosphere gas containing hydrogen gas as furnace gas,
A seal metal member 4 made of a thin plate made of, for example, stainless steel having a thickness of about 0.5 mm and hardly oxidizing and having one end fixed to the side plate 3a of the furnace wall 3, and an adhesive, a bolt and a nut attached to the surface of the seal metal member 4. A seal pad 5 made of an elastic material fixed by the above-described method is held by the furnace wall 3 located on both sides in the width direction of the metal band S, and is pressed against the seal pad 5 and the metal band S to seal the gas in the furnace. 1 is a seal device of a heat treatment furnace using an atmosphere gas containing hydrogen gas according to the present invention, which includes an elastic rotating roll 6 which performs the above-described process.

The seal pad 5 made of an elastic body fixed to the surface of the seal metal 4 is exposed to a flame in the event of a fire, so that at least its surface layer has a limiting oxygen index LOI value of 26.
It must be made of a material that satisfies the above, that is, a material that satisfies the condition that the minimum oxygen volume fraction required for maintaining the fiber burning is 26% or more.
Materials satisfying such conditions include JIS S6
Various sponges having a hardness defined by 050 of 10 to 50,
That is, the surface of at least the part of the elastic rotating roll 6 such as the NBR sponge, EPDM sponge, chloroprene rubber sponge, chlorosulfonated polyethylene sponge, chlorinated polyethylene sponge, hydrin rubber sponge, silicon rubber sponge, or fluororubber sponge on which the elastic rotating roll 6 rotates and slides ( In the surface layer), whether it is polyphenylene sulfide fiber, aramid fiber, aramid fiber and carbon fiber,
In some cases, a nonwoven fabric 5a made of either polyphenylene sulfide fiber and aramid fiber or polyphenylene sulfide fiber, aramid fiber and carbon fiber is attached or integrally attached by other methods.
Further, a nonwoven fabric 5a made of any of polyphenylene sulfide fiber, aramid fiber, aramid fiber and carbon fiber, polyphenylene sulfide fiber and aramid fiber, or polyphenylene sulfide fiber, aramid fiber and carbon fiber is provided on the surface of the sealing metal. In some cases, it is directly contacted and fixed to reduce air permeability with the outside air. In any of these cases, in the former case, the lower layer of the seal pad 5 is formed of an NBR sponge,
If an EPDM sponge, a chloroprene rubber sponge, a chlorosulfonated polyethylene sponge, a chlorinated polyethylene sponge, a hydrin rubber sponge, a silicone rubber sponge, or a fluorine rubber sponge is used, the surface layer of the seal pad 5 is protected by heat-resistant fibers. Because
Strong flame resistance, durability against short-time fires, and most preferably, the lower layer is a sponge in a closed cell shape with low air permeability, because the gas in the furnace does not leak from the sponge part. .

Then, as shown in FIGS. 2 and 3, an NBR sponge, an EPDM sponge, a chloroprene rubber sponge,
Contact with the elastic rotating roll 6 on the surface, whether or not it has a chlorosulfonated polyethylene sponge, chlorinated polyethylene sponge, hydrin rubber sponge, silicon rubber sponge, fluorine rubber sponge, etc. 5b Since the concave portion having the same curvature as the diameter of the roll body 6a of the elastic rotating roll 6 is formed in the portion, the contact circumferential length of the contact portion between the seal pad 5 and the elastic rotating roll 6 becomes longer, and the flow of the gas flows. The flow path resistance is increased, and the surface of the seal pad 5 is made of the above-described nonwoven fabric 5a made of fiber. This is preferable because pressure loss can be increased and gas leakage in the furnace can be effectively prevented.

On the other hand, the elastic rotating roll 6 has an outer surface of a roll body 6a made of chloroprene rubber, chlorosulfonated polyethylene, chlorinated polyethylene, hydrin rubber, silicon rubber or fluorine rubber having good flame resistance. It has been determined that a fire extinguisher in a short time because a fire extinguishing facility is attached and installed like a fire in the seal device 2 does not cause a phenomenon of deterioration, so that there is no problem in sealing performance. At the end of the elastic rotating roll 6, at least two or more pieces of fluorine having a small coefficient of dynamic friction having good fire resistance and heat resistance are provided between the both ends of the roll body 6 a and the furnace wall 3 from the roll body 6 a. Slip disk 6b made of synthetic resin whose main component is resin or FIG.
A rotating disk 6d using bearings as shown in
As long as it has an elastic disk 6c made of chloroprene rubber, chlorosulfonated polyethylene, chlorinated polyethylene, hydrin rubber, silicon rubber or fluoro rubber, which is a material having good fire resistance similar to the outer surface of the roll body 6a, a slip disk is provided. 6b and the rotating disk 6d prevent the rotational force of the elastic rotating roll 6 from being transmitted to the furnace wall 3, while the elastic disk 6c seals with an appropriate elasticity.
And / or the end of the roll body 6a of the elastic rotating roll 6 is worn and the sealing performance is reduced, and there is no phenomenon of deterioration due to a fire extinguished in a short time, and the sealing performance is not reduced. preferable.

[0019]

The sealing device 2 for a heat treatment furnace using an atmosphere gas containing hydrogen gas according to the present invention configured as described above in detail uses an atmosphere gas containing hydrogen gas as a gas in the furnace. A seal metal member 4 provided at the entrance and exit of the heat treatment furnace to be fixed, one end of which is fixed to the side plate 3a of the furnace wall 3, a seal pad 5 made of an elastic body fixed to the surface of the seal metal member 4, and a metal strip. The sealing device 2 is provided with a sealing pad 5 and elastic rotating rolls 6 held on the furnace wall 3 located on both sides in the width direction of the S and pressed against the seal pad 5 and the metal band S to seal the gas in the furnace. Since the surface of the pad 5 is made of a material satisfying the LOI value of 26 or more, the flame resistance is good, so that the gas in the furnace, which is an atmosphere gas containing hydrogen gas, leaks and becomes a gas mixed with oxygen in the air. Ignition Even fire occurs Te, sealing apparatus 2
A nitrogen gas is supplied to the inside of the furnace, and a carbon dioxide gas is blown to the outer surface of the sealing device 2 by a fire extinguisher attached to the sealing device 2 so that the fire is extinguished within a relatively short time. Burning on the surface of the pad 5,
There is no melting dropping and no change in the material. Therefore, even after the fire is extinguished, the operation can be restarted immediately without any deterioration in the sealing performance, without contaminating or damaging the elastic rotating roll 6.

That is, the polyphenylene sulfide fiber, which is a material constituting the surface of the seal pad 5, has a melting temperature of 285 ° C. and aramid fiber (para-aromatic polyamide fiber and meta-aromatic polyamide fiber). The para-system decomposes at 415 ° C and the meta-system decomposes at 371 ° C and self-extinguishes. Carbon fibers are inactive below 300 ° C and their LOI value is 26 or more, polyphenylene sulfide fiber or aramid fiber. Non-woven fabric 5a made of any of aramid fiber and carbon fiber, polyphenylene sulfide fiber and aramid fiber, or polyphenylene sulfide fiber, aramid fiber and carbon fiber has sufficient heat resistance in the case of short-term fire near seal pad 5. It has almost no deterioration. Chloroprene rubber constituting the outer surface of the elastic rotating roll 6;
Chlorosulfonated polyethylene, chlorinated polyethylene,
As described above, it has been confirmed that hydrin rubber, silicon rubber, or fluoro rubber has no melting or burning and has sufficient heat resistance in a short fire of about 10 seconds at most near the seal pad 5. . If the LOI value of the fiber used is less than 26, the self-extinguishing property is small, and the damage from burning and burning due to fire increases, and the operation is stopped to replace the seal pad 5, and the furnace gas is replaced with nitrogen gas. Although it depends on the furnace type, production often needs to be stopped for several days, and it is not suitable as a material constituting the surface.

In addition, from the front surface to the seal metal 4 where the seal pad 5 is in contact with the back surface, all of the above-mentioned polyphenylene sulfide fiber, aramid fiber, aramid fiber and carbon fiber, polyphenylene sulfide fiber and aramid fiber are used. When the nonwoven fabric 5a is made of any one of polyphenylene sulfide fiber, aramid fiber and carbon fiber, there is no problem in terms of heat resistance. However, since the nonwoven fabric 5a is inferior in terms of the gas-tightness in the furnace because it has air permeability,
NBR sponge, EPDM sponge, chloroprene rubber sponge, chlorosulfonated polyethylene sponge, chlorinated polyethylene, hydrin rubber sponge, silicon rubber sponge, or fluorine rubber sponge 5b having a hardness of 10 to 50 specified by JIS S 6050 having low air permeability.
At least the surface (surface layer) which is in direct contact with the elastic rotating roll 6 is made of polyphenylene sulfide fiber, aramid fiber, aramid fiber and carbon fiber, polyphenylene sulfide fiber and aramid fiber, polyphenylene sulfide fiber and aramid A nonwoven fabric 5a made of any one of fibers and carbon fibers is attached or attached by various methods, and NBR sponge, EPDM sponge, chloroprene rubber sponge, chlorosulfonated polyethylene sponge, Chlorinated polyethylene sponge,
The hydrin rubber sponge, silicon rubber sponge or fluorine rubber sponge 5b is a sponge in the form of a closed cell having a low air permeability as much as possible. Only the surface made of the above-mentioned fiber which comes into contact with the elastic rotating roll 6 has air permeability, and the rest is air permeable. It is preferable to use a structure having no sealing property for improving the sealing property. By improving the sealing property, the consumption of expensive atmospheric gas is reduced, and since there is no invading air, the surface of the metal strip S is not colored due to oxidation and the quality is improved. In addition, damage at the time of fire occurrence is small.

As described above, the sealing pad 5 is
NBR sponge, EPDM between the surface and non-woven fabric 5a
When using a structure in which a sponge, a chloroprene rubber sponge, a chlorosulfonated polyethylene sponge, a chlorinated polyethylene sponge, a hydrin rubber sponge, a silicon rubber sponge or a fluorine rubber sponge 5b is interposed,
Hardness specified by JIS S 6050 is 10-5
If the hardness specified in JIS S 6050 is less than 10, the material is too soft and the force for sufficiently sealing the unevenness of the surface of the elastic rotating roll 6 cannot be transmitted to the nonwoven fabric 5a. , The rigidity of the seal pad 5 is insufficient and the sealing effect is not obtained.
If the hardness specified in S6050 exceeds 50, the rigidity is too large and the flexibility corresponding to small irregularities on the surface of the elastic rotating roll 6 is insufficient, or the elastic rotating roll 6 which is partially pressed strongly and is soft. This is because the surface is scratched, the fibers in the surface layer become fluffy, and hair loss occurs. When the hardness is from 10 to 50, it is pressed uniformly over the whole for moderate flexibility, there is no fluff and no hair loss, there is no pushing flaw on the metal band S in the next rolling step, and the surface quality is low. improves.

Even when the entirety of the seal pad 5 is made of the nonwoven fabric 5a, the NBR sponge, EPDM sponge, chloroprene rubber sponge, chlorosulfonated polyethylene sponge, chlorine Even when the structure is such that a polyethylene sponge, a hydrin rubber sponge, a silicone rubber sponge, or a fluorine rubber sponge 5b is interposed, the elastic rotation of the surface of the seal pad 5 with the elastic rotation roll 6 as shown in FIGS. Roll body 6 of roll 6
If a concave portion having a curvature substantially equal to the diameter of a is formed so as to be at least 1/15 or more of the circumferential length of the elastic rotating roll 6, the contact circumferential length between the seal pad 5 and the elastic rotating roll 6 becomes long. The flow resistance of the outflowing gas is increased, and the portion of the surface of the seal pad 5 that comes into contact with the elastic rotating roll 6 is formed with a portion that produces an action similar to that of the labyrinth packing, which increases the pressure loss of the gas. Thus, the effect of sealing the gas in the furnace is further improved. If the amount of atmospheric gas leaking out is small, the momentum of the flame in the event of a fire is small, and accordingly the durability is increased and the damage is small.

The elastic rotating roll 6 includes a roll body 6a whose outer surface in contact with the metal band S is made of chloroprene rubber, chlorosulfonated polyethylene, chlorinated polyethylene, hydrin rubber, silicon rubber or fluoro rubber, and a roll body 6a. Roll body 6a between the furnace wall 3 on both sides
Use a slip disk 6b or bearing made of a synthetic product whose main component is a heat-resistant and flame-resistant fluororesin whose electrical resistivity value of at least the slip surface is 1 to 10 ⁷ Ω · cm. A rotating disk 6d and an elastic disk 6c made of chloroprene rubber, chlorosulfonated polyethylene, chlorinated polyethylene, hydrin rubber, silicon rubber or fluororubber having a flame resistance of 1 to 10 ⁷ Ω · cm. With such a structure, the transmission of the rotational force between the end of the roll body 6a and the furnace wall 3 is interrupted, and the end of the furnace wall 3 and / or the elastic rotating roll 6 is not worn and the sealing performance is improved. It does not lower, and no static electricity is generated at the end of the elastic rotating roll 6 due to continuous rotational friction, and no fire due to spark occurs. In addition, even if a fire occurs due to a red-hot fallen object such as a refractory piece or the like, the fire resistance and heat resistance of the elastic rotating roll 6 and the like do not cause immediate burning or melting damage, and the sealing property is not lost. However, since the fire does not increase, the fire can be extinguished quickly and the damage is small.

As described in detail above, the seal device of the heat treatment furnace using the atmosphere gas containing hydrogen gas according to the present invention is configured such that at least the surface of the seal pad 5 constituting the seal device 2 is made of a material having heat resistance. Has been
Even if a fire that ignites the leaked gas in the furnace and is extinguished in a short time occurs, the sealing pad 5 constituting the sealing device 2 is deteriorated or melted and dropped, thereby deteriorating the sealing performance. If the elastic rotating roll 6 is also made of a heat-resistant material, it can ignite the leaked gas in the furnace if the elastic rotating roll 6 is made of a material having heat resistance. Even if a fire that is extinguished due to the fire occurs, it is possible to prevent the occurrence of a phenomenon in which the elastic rotating roll 6 constituting the sealing device 2 is deteriorated or melted and the sealing performance is deteriorated. Is extremely small, has an epoch-making effect of enabling a stable operation of a heat treatment furnace using an atmosphere gas containing hydrogen gas, and its industrial value is very large.

[Brief description of the drawings]

FIG. 1 is an enlarged explanatory side view showing one embodiment of an end structure of an elastic rotating roll in the apparatus of the present invention.

FIG. 2 is an enlarged cross-sectional explanatory view showing one embodiment in the vicinity of a seal pad portion made of an elastic body fixed to a surface of a seal metal in the device of the present invention.

FIG. 3 is an enlarged sectional explanatory view showing another embodiment in the vicinity of a seal pad portion made of an elastic body fixed to the surface of a seal fitting in the device of the present invention.

FIG. 4 is an enlarged sectional explanatory view showing an embodiment of a rotating disk using a bearing disposed between a roll body of an elastic rotating roll and furnace walls on both sides in the apparatus of the present invention.

FIG. 5 is a structural explanatory diagram of a general vertical bright annealing furnace for a stainless steel strip.

FIG. 6 is an enlarged front view of a conventional sealing device provided on an outlet side.

FIG. 7 is a partial side view of FIG. 6;

FIG. 8 is a diagram illustrating a comparison of a limiting oxygen index (LOI value) for each material.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Furnace body 2 Sealing device 2 'Conventional sealing device 3 Furnace wall 3a Side plate 4 Seal metal 4' Seal metal of conventional sealing device 5 Seal pad 5a Non-woven fabric 5b NBR sponge, EPDM sponge, chloroprene rubber sponge, chlorosulfonated polyethylene sponge , Chlorinated polyethylene sponge, hydrin rubber sponge, silicon rubber sponge or fluorine rubber sponge 5 'Seal pad of conventional sealing device 6 Elastic rotating roll 6a Roll body 6b Slip disk 6c Elastic disk 6d Rotating disk 6' Conventional sealing device Elastic rotating roll 6d 'Roll shaft 6e' Bearing 7 Roll opening / closing mechanism 7a Piston rod 7b Lever 7c Fixing pin S Metal band

Claims (10)

(57) [Claims] 1. A seal fitting (4) provided at the entrance and exit of a heat treatment furnace using an atmosphere gas containing hydrogen gas as a furnace gas, and having one end fixed to a side plate (3a) of a furnace wall (3). And a seal pad (5) made of an elastic body fixed to the surface of the seal hardware (4), and a seal pad held on a furnace wall (3) located on both sides in the width direction of the metal strip (S). (5) The sealing pad (5), wherein the sealing pad (5) includes an elastic rotating roll (6) pressed against the metal strip (S) to seal the gas in the furnace.
The atmosphere gas containing hydrogen gas, characterized in that the surface of the material is made of a material having a limit oxygen index (index of a minimum oxygen volume fraction necessary for maintaining the fiber burning) LOI value of 26 or more. Sealing equipment for the heat treatment furnace used. 2. The atmosphere gas containing hydrogen gas according to claim 1, wherein the outer surface of the elastic rotating roll (6) is made of chloroprene rubber, chlorosulfonated polyethylene, chlorinated polyethylene, hydrin rubber, silicon rubber or fluorine rubber. Sealing equipment for heat treatment furnace. 3. A roll body (6) is provided between the elastic rotating roll (6 ) and the furnace wall (3) on both sides of the roll body (6a).
a) a slip disk (6b) made of a synthetic product containing fluororesin as a main component and a rotating disk (6d) using bearings and chloroprene rubber;
Chlorosulfonated polyethylene, chlorinated polyethylene,
The sealing device for a heat treatment furnace using an atmosphere gas containing hydrogen gas according to claim 1 or 2, comprising an elastic disk (6c) made of hydrin rubber, silicon rubber, or fluorine rubber. Wherein an electrical resistivity of at least the slip surface of the slip disks (6b) is 1 to 10 ⁷ Omega · cm, electrical resistivity value of the elastic disk (6c) is 1 to 10 ⁷
The sealing device for a heat treatment furnace using an atmosphere gas containing hydrogen gas according to claim 3, which is Ω · cm. 5. The sealing pad (5) is entirely made of JI
An elastic body having a hardness from 10 to 50 defined by S S 6050, the surface of the seal pad (5), polyphenylene sulfide fibers or, or aramid fibers, aramid fibers and or carbon fibers, polyphenylene sulfide fibers and aramid fibers 5. A non-woven fabric (5a) comprising any one of polyphenylene sulfide fiber, aramid fiber and carbon fiber.
A sealing device for a heat treatment furnace using an atmosphere gas containing hydrogen gas as described in the above item. 6. An elastic body constituting a seal pad (5) is made of an NBR sponge, an EPDM sponge, a chloroprene rubber sponge, a chlorosulfonated polyethylene sponge, a chlorinated polyethylene sponge, a hydrin rubber sponge, a silicone rubber sponge or a fluorine rubber sponge ( 5
The sealing device for a heat treatment furnace using an atmosphere gas containing hydrogen gas according to any one of claims 5 to 7. 7. An NBR sponge for a seal pad (5),
7. The sponge according to claim 6, wherein the EPDM sponge, chloroprene rubber sponge, chlorosulfonated polyethylene sponge, chlorinated polyethylene sponge, hydrin rubber sponge, silicon rubber sponge, or fluorine rubber sponge (5b) is a sponge with low air permeability. Sealing device for heat treatment furnace using atmosphere gas containing hydrogen gas. 8. A polyphenylene sulfide fiber, an aramid fiber, an aramid fiber and a carbon fiber, a polyphenylene sulfide fiber and an aramid fiber, or a polyphenylene sulfide fiber, wherein the seal pad (5) is in direct contact with and fixed to the surface of the sealing metal. The sealing device for a heat treatment furnace using an atmosphere gas containing hydrogen gas according to any one of claims 1 to 5, wherein the sealing device is a nonwoven fabric (5a) made of any one of aramid fibers and carbon fibers. 9. A concave portion having a curvature substantially equal to the diameter of the roll body (6a) of the elastic rotating roll (6) is formed in a portion of the surface of the seal pad (5) in contact with the elastic rotating roll (6). A sealing device for a heat treatment furnace using an atmosphere gas containing hydrogen gas according to any one of claims 1 to 8. 10. A configuration in which the contact portion of the surface of the seal pad (5) with the elastic rotating roll (6) is at least 1/15 of the circumference of the elastic rotating roll (6). A sealing device for a heat treatment furnace using an atmosphere gas containing hydrogen gas as described in (1).