JP4796467B2 - Horizontal flameproof furnace and flameproofing method - Google Patents

Description

  The present invention relates to a horizontal flameproofing furnace and a flameproofing method using a horizontal flameproofing furnace.

2. Description of the Related Art Conventionally, there is known a flameproofing furnace that continuously performs a flameproofing treatment on a workpiece in manufacturing a long article such as a film, a sheet, a fiber (hereinafter referred to as a workpiece). In this flameproofing furnace, for example, in the case of carbon fiber, a precursor fiber made of, for example, polyacrylonitrile-based fiber is subjected to a flameproofing treatment that continuously flameproofs at 200 ° C. to 300 ° C. in a heat treatment chamber. At this time, decomposition gases such as cyanide, ammonia, and carbon monoxide are generated in the heat treatment furnace by the oxidation reaction of the precursor fibers. Since this decomposition gas is toxic, it must be recovered and subjected to a gas treatment such as a combustion treatment.
In order to prevent such cracked gas from leaking out of the furnace fiber precursor fiber insertion port, a seal chamber is provided adjacent to the heat treatment chamber insertion port, and is further covered outside the insertion port. There has been proposed a heat treatment furnace provided with an air curtain means for blowing air outside the furnace main body toward the processed object (for example, see Patent Document 1).
Further, in order to suppress temperature unevenness in the heat treatment furnace, there has been proposed a flame-resistant heat treatment apparatus having a mechanism in which a slit is provided at the insertion port of the heat treatment furnace and heated air is ejected from the slit into or out of the furnace (for example, , See Patent Document 2).
In addition, in the flameproofing treatment using these flameproofing furnaces, in order to treat a large amount of precursor fibers efficiently and continuously, a plurality of precursor fiber insertion ports are provided in the flameproofing furnace, Repeatedly inserting and inserting into the heat treatment chamber while turning outside the furnace. For this reason, conventionally, a horizontal flameproof furnace in which a plurality of paths are provided in the vertical direction and the precursor fiber travels in the horizontal direction has been used. Due to the chimney effect in the heat treatment chamber, these cause a pressure distribution in which the upper pressure is high and the lower pressure is low.
JP 2004-143647 A WO02 / 077337 pamphlet

However, in the conventional horizontal flameproofing furnace, fine adjustment of the air speed of the air curtain means for each pass is complicated and difficult, so it is easy to suck low temperature outside air from the insertion port in the pass below the heat treatment chamber, There was a problem that the decomposition gas in the heat treatment chamber was likely to leak from the insertion port.
As a result, the decomposition gas generated in the heat treatment chamber leaks from the insertion port above the heat treatment chamber into the seal chamber, thereby increasing the amount of gas required for the combustion treatment. In addition, at the insertion port below the heat treatment chamber, there is a concern that the temperature in the heat treatment chamber may be lowered by sucking low temperature air from the seal chamber.
For example, in Patent Document 1, an object to be processed passes above and below one air curtain means, and from two nozzles, one to the lower surface of the object to be processed passing above, and the other to be processed passing below. Because of the structure in which air is ejected toward the upper surface of the slab, it was not possible to set the optimum ejection speed according to the seal chamber pressure at each stage. Therefore, in order to surely prevent the cracked gas from leaking, it is necessary to increase the inflow amount of air outside the heat treatment chamber from the optimum condition.

  Accordingly, the present invention solves the problems of the conventional horizontal flameproofing furnace and suppresses the inflow of outside air into the heat treatment chamber, and completely leaks the cracked gas generated in the heat treatment chamber to the outside. An object of the present invention is to provide a horizontal flameproof furnace capable of maintaining the temperature in the heat treatment chamber by cutting off and reducing the amount of gas that needs to be burned.

In order to solve the above-described problems, the present invention provides a horizontal flameproof furnace for continuously heat-treating an object to be treated in a heat treatment chamber, and placing the object on an outer wall of a seal chamber connected to the heat treatment chamber. insert, the slit-shaped insertion port opened form for挿出, a pair of nozzles for ejecting air toward the outside in and the treatment object of the insertion opening vertically sandwiching the insertion hole, the pair for each nozzle of, characterized in that the flow rate adjusting mechanism is connected to a single air supply passage provided.
By comprising in this way, the pressure of the air supplied to an up-and-down nozzle by a single air supply path, a flow volume, etc. can be made substantially equal. Further, by adjusting the flow rate, pressure, and the like of the air supplied to the single air supply path, the wind speed and the like of the air ejected from the nozzles arranged above and below can be adjusted simultaneously. Thereby, according to the vertical pressure distribution generated in the heat treatment chamber, the wind speed and the like of the upper and lower nozzles can be simultaneously adjusted to optimum values.

  According to the present invention, since the wind speed of the upper and lower nozzles can be easily adjusted to an optimum value for each pass according to the pressure distribution in the heat treatment chamber, the flow of outside air into the heat treatment chamber is suppressed, and the cracked gas Leakage to the outside can be completely blocked. Therefore, the temperature in the heat treatment chamber can be easily maintained, and the amount of gas required for the combustion treatment can be reduced.

Hereinafter, embodiments of the horizontal flameproofing furnace of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1 (a), the horizontal flameproofing furnace 1 includes a box-shaped heat treatment chamber 2. The heat treatment chamber 2 is connected to a hot air circulation device (not shown) for circulating hot air therein. The heat treatment chamber 2 is provided with an exhaust port 30. The exhaust port 30 is connected to the fan 14 via an exhaust path 31. A flow rate adjusting mechanism 13 such as a valve is provided in the middle of the exhaust passage 31. The fan 14 is connected to an external gas recovery processing device (not shown).

  Sealing chambers 4, 4 are connected to outer walls 3, 3 on the left and right sides of the heat treatment chamber 2 in the drawing. The outer walls 5 and 5 of the seal chambers 4 and 4 are respectively provided with slit-like insertion ports 7 and 7 'for inserting and removing the object to be treated, for example, the precursor fiber A made of polyacrylonitrile fiber. . Similarly, the outer walls 3, 3 of the heat treatment chamber 2 are also provided with insertion ports 6, 6 ′ corresponding to the insertion ports 7, 7 ′ of the seal chambers 4, 4. The insertion ports 6 and 6 ′ of the heat treatment chamber 2 and the insertion ports 7 and 7 ′ of the seal chambers 4 and 4 are provided in three stages in the vertical direction of the seal chambers 4 and 4, respectively.

Inside the seal chambers 4, 4 are provided partition plates 12 that divide the insertion ports 7, 7 ′ provided in three stages in the vertical direction into separate compartments 4 a, 4 b, 4 c. Further, the seal chambers 4 and 4 are provided with exhaust ports 15 and 15, and are connected to the exhaust fans 17 and 17 through the exhaust passages 32 and 32. As shown in FIG. 1 (b), the exhaust ports 15 are respectively provided in the sections 4 a, 4 b, 4 c where the seal chambers 4, 4 are divided by the partition plate 12. A flow rate adjusting mechanism 34 such as a valve is provided in each exhaust passage 33 connected to each exhaust port 15.
Here, the length Ls of the precursor fiber A in the running direction of the seal chamber 4 is appropriately determined in consideration of the properties of the fibers, the indoor cleaning and maintenance workability, and the like.

On the outer walls 5 and 5 of the seal chambers 4 and 4, air curtain means 8 having a pair of nozzles 10a and 10b above and below are provided so as to sandwich the insertion ports 7 and 7 ', respectively. The nozzles 10a and 10b are attached to the front end corner portion of the support portion 9 which is preferable in terms of pressure application.
As shown in FIG. 1B, the upper and lower nozzles 10a, 10b of the air curtain means 8 are connected to a single air supply path 35, and a flow rate adjusting mechanism 21 such as a valve is provided in the air supply path 35, for example. It has been. Each flow rate adjusting mechanism 21 is further connected to an air supply fan 24 via a common air supply path 37.
As shown in FIG. 2, the nozzles 10 a and 10 b arranged above and below the insertion ports 7 and 7 ′ of the outer walls 5 and 5 of the seal chambers 4 and 4 are directed outward from the insertion ports 7 and 7 ′. , 7 ′, which is formed between the two plate members by the two plate members arranged toward the precursor fiber A inserted and inserted, and is arranged so as to have an angle θ with respect to the precursor fiber A. Yes. At this time, the angle θ is in a range larger than 0 ° and smaller than 90 °. Furthermore, it is more preferable to set it as the range of 30 degrees or more and 60 degrees or less. Here, the interval Dn between the nozzles 10a and 10b facing each other is set to a range of 4 mm or more and 60 mm or less. Furthermore, it is more preferable that it is the range of 15 mm or more and 40 mm or less.

As shown in FIGS. 2 and 3, the tips of the nozzles 10a and 10b of the air curtain means 8 are slit-shaped jets 20a and 20b. The air supply path 35 is provided with a pressure gauge 22 for measuring the pressure of the supplied air. Here, the length Ln of the air curtain means 8 in the workpiece traveling direction is appropriately determined in consideration of the blowing air speed from the nozzles 10a and 10b, the ejection unevenness in the width direction, and the like.
As shown in FIG. 4A, the single air supply path 35 connected to the air curtain means 8 is formed into upper and lower air supply paths 35a and 35b corresponding to the upper and lower nozzles 10a and 10b inside the air curtain means 8. Branched. At the branch point of the air supply path 35 inside the air curtain means 8, a substantially triangular cross section is arranged with the apex directed toward the branch point so that the supplied air is uniformly distributed to the upper and lower air supply paths 35a, 35b. A shaped distribution plate 25 is provided.

As shown in FIG. 4 (b), in front of the outlets 20a, 20b of the air supply passages 35a, 35b in the air curtain means 8, a perforated plate 18, as a screen-like rectifying means in which a large number of holes are formed, 19 is provided. Groove-shaped rails 38 and 39 are provided above and below the perforated plates 18 and 19, and the end portions of the perforated plates 18 and 19 are sandwiched and fixed by the rails 38 and 39. Further, the side walls 40, 40 of the support portion 9 of the air curtain means 8 are fixed by a removable locking tool such as a bolt (not shown).
Here, the aperture ratio and the number of installations of the perforated plates 18 and 19 are appropriately determined according to the ratio of the width and height of the support portion 9, the speed of air blown from the jet outlet 20, and the like.

  Further, as shown in FIG. 1 (a), a roll 11 is disposed on the outside of the outer walls 5 and 5 of the seal chambers 4 and 4 so that the precursor fibers A are routed corresponding to the heights of the insertion ports 7 and 7 '. Has been. The rotating shaft of the roll 11 is connected to a motor, a controller, a power source, etc. (not shown) and can rotate freely. The surface of the roll 11 has a friction coefficient suitable for transmitting power to the precursor fiber A.

Next, the operation of this embodiment will be described.
As shown in FIG. 1A, a plurality of precursor fibers A are inserted from the uppermost insertion port 7 of the seal chamber 4 on the left side of the flameproofing furnace 1 in a state where they are aligned in parallel with the paper surface in the vertical direction. The Next, the precursor fiber A passes through the insertion port 6 of the outer wall 3 of the heat treatment chamber 2 and is inserted from the insertion port 6 ′ of the outer wall 3 facing the heat treatment chamber 2. Further, the precursor fiber A passes through the insertion port 7 ′ of the outer wall 5 of the seal chamber 4 connected to the heat treatment chamber 2 and is inserted out of the flameproofing furnace 1. The precursor fiber A inserted outside the flameproofing furnace 1 is folded back so as to be wound around the roll 11 outside the seal chamber 4, and the insertion port 7 below the inserted insertion port 7 'is inserted. 'Is again inserted into the flameproofing furnace 1.

  The precursor fiber A inserted into the flameproofing furnace 1 again is inserted in the reverse direction to the outside of the flameproofing furnace 1 through the same path, and is wound around the roll 11 outside the flameproofing furnace 1 and turned back. . In this way, the precursor fiber A is repeatedly inserted and removed from the flameproofing furnace 1 while being repeatedly folded outside the flameproofing furnace 1 by the roll 11, and passes through the inside of the flameproofing furnace 1 so as to meander. . At this time, power is given to the precursor fiber A by the rotation of the roll 11 and the friction of the surface of the roll 11, and the precursor fiber A is continuously fed in the direction of the arrow X in FIG.

  On the other hand, hot air circulates inside the heat treatment chamber 2 by a hot air circulation device (not shown), and is maintained at a temperature of 200 ° C. to 300 ° C., for example. Therefore, the precursor fiber A continuously inserted repeatedly inside the heat treatment chamber 2 is gradually made flame resistant in the heat treatment chamber 2. At this time, a decomposition gas such as cyanide, ammonia, and carbon monoxide is generated in the heat treatment chamber 2 by the oxidation reaction of the precursor fiber A. The generated cracked gas is discharged from the exhaust port 30 provided in the heat treatment chamber 2 by the exhaust fan 14, and is recovered and processed by an external gas recovery processing device. Further, the adjustment of the exhaust amount by the exhaust fan 14 can be performed by a flow rate adjusting mechanism 13 such as a valve, for example.

  Further, the inside of the seal chambers 4, 4 becomes a negative pressure by sucking the gas inside by the exhaust fans 17, 17. Further, the heat treatment chamber 2 is heated to generate a vertical pressure distribution in which the upper part has a high pressure and the lower part has a low pressure.

Here, as shown in FIG. 1 (b), the air outside the flameproofing furnace 1 is supplied to the nozzles 10 a and 10 b of the air curtain means 8 by the air supply fan 24 and ejected toward the precursor fiber A. Form an air curtain.
As shown in FIGS. 3 and 4 (a), air supplied from a single air supply path 35 connected to the air curtain means 8 is provided at a branch point of the air supply path 35 inside the air curtain means 8. The distribution plate 25 is uniformly distributed up and down and is supplied to the air supply passages 35a and 35b corresponding to the upper and lower nozzles 10a and 10b. The air distributed to the upper and lower air supply passages 35a and 35b is uniformly rectified by pressure loss when passing through the perforated plates 18 and 19. The vertically distributed and rectified air is jetted at substantially the same wind speed from the upper and lower jet outlets 20a and 20b at the tips of the nozzles 10a and 10b to form an air curtain that collides with the precursor fiber A from above and below. Here, by providing a plurality of perforated plates 18 and 19, it is possible to suppress the ejection unevenness while suppressing the pressure loss lower than when installing one perforated plate or the like having a smaller aperture ratio.

Further, as shown in FIG. 1B, by connecting the air curtain means 8 to each single air supply path 35, the flow rate adjusting mechanism 21 provided in each air supply path 35 is adjusted, so that each air The wind speed of the air ejected from the upper and lower nozzles 10a, 10b of the curtain means 8 can be adjusted simultaneously. Therefore, fine adjustment of the wind speed for each of the insertion ports 7 and 7 'is facilitated as compared with the conventional case.
Here, when the wind speed of the air curtain formed by the air curtain means 8 is 1 to 50 m / sec, leakage of cracked gas and intrusion of outside air into the heat treatment chamber 2 can be more reliably prevented. In addition, when the wind speed of the air curtain is 1 m / second or more, outside air does not enter the heat treatment chamber 2. If the wind speed is 50 m / sec or less, the decomposition gas in the heat treatment chamber 2 is not leaked by the air curtain airflow.

Further, at this time, the angle θ of the nozzles 10a and 10b is set in a range larger than 0 ° and smaller than 90 °, more preferably in a range from 30 ° to 60 °, and the air ejection angle θ is set in the above range. Gas leakage can be reliably prevented, and inflow of outside air into the heat treatment chamber 2 can be suppressed.
Further, the appropriate blown air speed for suppressing the inflow of outside air changes according to the pressure inside the seal chambers 4 and 4. That is, in order to set the pressure in each of the compartments 4a, 4b, and 4c of the seal chambers 4 and 4 to individual values corresponding to the pressure distribution in the vertical direction inside the heat treatment chamber 2, air ejected from the nozzles 10a and 10b. Need to be adjusted to an optimum value for each of the sections 4a, 4b, and 4c.

At this time, according to the present embodiment, as shown in FIG. 1B, the air curtain means of each insertion port 7, 7 ′ is adjusted by individually adjusting the flow rate adjusting mechanism 21 of each air curtain means 8. The wind speed of the air ejected from the eight nozzles 10a and 10b can be set individually. Therefore, the inflow of the external air to each compartment 4a, 4b, 4c of the seal chamber 4 can be effectively suppressed according to the pressure in each compartment 4a, 4b, 4c.
Therefore, as shown in FIG. 1 (b), the flow rate of the gas discharged from the exhaust port 15 provided in each of the compartments 4a, 4b, 4c is adjusted by the fluid regulating mechanism 21, so that each of the compartments 4a, 4b, 4c The pressure can be set individually. Therefore, the pressure in each of the compartments 4 a, 4 b, 4 c of the seal chambers 4, 4 can be individually set to an appropriate pressure according to the vertical pressure distribution in the heat treatment chamber 2.

As a result, in the upper section 4c of the seal chamber 4 adjacent to the upper portion of the heat treatment chamber 2 having a high pressure, the internal pressure is set to a negative pressure and a high pressure according to the pressure in the heat treatment chamber 2, and the heat treatment chamber having a low pressure is used. In the lower section 4 a of the seal chamber 4 adjacent to the lower portion of 2, the internal pressure can be set to a negative pressure and a lower pressure according to the pressure inside the heat treatment chamber 2.
For example, if the temperature difference between the inside of the heat treatment chamber 2 and the outside air is 250 ° C., and the height difference in the height direction inside the heat treatment chamber 2 is 1 m, if the pressure in the upper portion of the heat treatment chamber 2 is +1.5 P, the adjacent seal chamber 4 The pressure in the upper section 4c is set to -0.5P. If the pressure in the lower part of the heat treatment chamber 2 is −3.8P, the pressure in the lower section 4a of the adjacent seal chamber 4 is set to −3.5P.
If it does in this way, the quantity of the air with the low temperature in the seal chambers 4 and 4 which flows in into the heat processing chamber 2 from the insertion ports 6 and 6 'of the heat processing chamber 2 lower part will be suppressed, and the temperature in the heat processing chamber 2 will fall. Can be prevented.

  In addition, it is possible to suppress the amount of gas inside the heat treatment chamber 2 leaking from the insertion ports 6 and 6 ′ above the heat treatment chamber 2 to the seal chambers 4 and 4. Further, by setting the pressure inside the seal chambers 4 and 4 to a negative pressure lower than the pressure outside the seal chambers 4 and 4, the cracked gas leaking inside the seal chambers 4 and 4 leaks outside the flameproofing furnace 1. This can be completely prevented. For example, by setting the pressure in the seal chambers 4 and 4 to a pressure range of −10 to −0.3 Pa, the cracked gas can be reliably sent to the gas recovery processing device.

As described above, according to the present embodiment, fine adjustment of the wind speed of the air curtain means 8 for each pass is facilitated, the flow of outside air into the heat treatment chamber 2 is suppressed, and the temperature in the heat treatment chamber 2 is reduced. Can be maintained. In addition, the amount of gas that needs to be burned can be reduced by completely blocking leakage of the cracked gas generated in the heat treatment chamber 2 to the outside.
In addition, when the rails 38 and 39 are provided inside the air curtain means 8 so that the porous plates 18 and 19 can be removed, when the porous plates 18 and 19 are accumulated for a long time, The perforated plates 18 and 19 can be taken out of the air curtain means 8 and cleaned. Therefore, the flameproofing furnace 1 can be easily maintained, and the productivity of the flameproofing process can be improved.

Further, since the air ejected from the nozzles 10a and 10b is air outside the heat treatment chamber 2, energy for heating the air curtain air can be saved, and the external work environment can be affected. There is no. Therefore, the cost of flameproofing treatment can be reduced and the safety of the work environment can be improved.
Further, since the distance between the opposed nozzles 10a and 10b is set to 4 mm or more, the precursor fiber A does not contact the air curtain means 8, and the quality of the product is not deteriorated. Further, by setting the thickness to 60 mm or less, the gas blowing speed necessary for sealing can be reduced. Therefore, it is possible to prevent the pressure loss at the perforated plates 18 and 19 from increasing and the load on the air supply equipment such as the air supply fan 24 from increasing.

In addition, this invention is not restricted to embodiment mentioned above, The precursor fiber A can be made to drive | work in the up-down direction 1 step-dozens of steps according to a condition.
In the present embodiment, the case where the precursor fiber A made of polyacrylonitrile fiber is subjected to flame resistance treatment has been described. However, it is also possible to use the horizontal flame resistance furnace 1 of the present invention for other objects to be treated. .
Moreover, it is preferable that the upper and lower opening dimensions of the insertion ports 6 and 6 ′ and the insertion ports 7 and 7 ′ be as narrow as possible within a range in which the precursor fiber A can pass without contact. This is because it is difficult for gas to flow through the entrance. Therefore, it is preferable that each doorway is a slit whose opening size can be adjusted in the vertical direction.

The air curtain means 8 is most preferably installed outside all the insertion ports 7 and 7 ′ in order to suppress the exhaust amount from the seal chamber 4. However, it is also possible not to install the air curtain means 8 in some of the insertion ports 7 and 7 ′. In that case, it is preferable that the air curtain means 8 is installed in the insertion ports 7 and 7 'positioned below, and the air curtain means 8 is not installed in the insertion ports 7 and 7' positioned above. It is preferable that an exhaust port 15 is provided in the seal chamber 4 where the air curtain means 8 is not installed, and the exhaust fan 17 exhausts air from the exhaust port 15. Even when the air curtain means 8 is installed outside all the insertion ports 7, 7 ′, it is preferable to provide the exhaust port 15 above the seal chamber 4.
The air curtain means 8 may have a structure in which gas is supplied from both ends in the width direction. Moreover, the partition plate 12 does not need to be provided in each step so as to partition all the steps of the seal chamber. Further, if the inside of the seal chamber 4 can be made negative by exhausting with the exhaust fan 14 provided in the heat treatment chamber 2, the seal chamber 2 may not include the exhaust port 15 and the exhaust 17 fan.

In the embodiment described above, only two porous plates 18 and 19 are used as the rectifying means. However, the porous plate and the net may be combined, or only the net may be used. Good. Further, the fixing method of the rectifying means is not limited to the rail as long as it can be removed. Moreover, the mounting position of the rail is not limited to the top and bottom of the rectifying means. The material of the perforated plate or the like can be used as long as it is not deformed by wind pressure, but a metal material is preferably used. In addition to the perforated plate and the net, a rectifying means having an rectifying effect such as an orifice can be used.
The gas supplied to the air curtain may not be air.

The following examples further illustrate the present invention.
As shown in FIG. 5, as a simulated one-stage heat treatment chamber 2, a seal chamber 4 and air curtain means 8 are provided on one outer wall 3, and an exhaust fan 14 for setting the heat treatment chamber 2 to a negative pressure, a damper A flow rate adjusting mechanism 13 is provided. The insertion ports 6 and 6 ′ and the insertion port 7 each have an opening length of 2000 mm in the direction perpendicular to the paper surface and an opening height Di of 40 mm.
The length Ln of the support portion 9 of the air curtain means 8 was 400 mm, the openings of the nozzles 10 a and 10 b were 2000 mm in the direction perpendicular to the paper surface, and the opening width Wn was 2 mm. The distance Dn between the nozzles 10a and 10b facing each other was 40 mm.

  The nozzles 10a and 10b of the air curtain means 8 are provided with two perforated plates having an opening ratio of 3.8% as shown in FIG. 4 (b), and gas is supplied from the air supply passage 35 as shown in FIG. 4 (a). It is distributed and has a structure in which gas is ejected from upper and lower ejection ports 20a and 20b of the object to be processed. As shown in FIG. 3, a flow rate adjusting mechanism 21 such as a damper is provided.

  The inside of the heat treatment chamber 2 generates a pressure difference in the height direction due to the chimney effect. When the temperature difference from the outside air is 250 ° C. and the difference in the height direction is 1 m, the pressure difference in the height direction is about 5.3 Pa. . Assuming an actual flameproofing furnace, the pressure in the seal chamber 4 is −2 Pa, the adjustment of the blowing air speed from the nozzles 10 a and 10 b and the exhaust fan 14 so that the outside air flows in all the places of the insertion port 7. The displacement was adjusted by the flow rate control damper 13. At this time, the average jet velocity from the nozzles 10a and 10b was 6 m / s, and the jet unevenness at each 21 points in the width direction perpendicular to the paper surface was ± 6% of the average value for 10a and 10b. The average inflow velocity at the insertion port 7 was 0.2 m / s. The atmospheric temperature was 30 ° C.

  The direction of gas flow was measured by observing the flow of smoke using a smoke tester manufactured by Gastec. Moreover, the air curtain blowing wind velocity was measured using an Anemo Master 6071 anemometer manufactured by Kanomax. The average inflow velocity at the insertion port 7 was calculated by measuring the exhaust amount by the exhaust fan 14 and the inflow amount from the insertion port 6 ′ using an anemo master 6141 anemometer manufactured by Kanomax. The pressure in the seal chamber 4 was measured using a Manostar gauge fine differential pressure gauge manufactured by Yamamoto Electric Co., Ltd.

The same as Example 1 except that the pressure in the seal chamber 4 was set to −6 Pa.
As in Example 1, when the adjustment was performed, the average blowing wind speed from the nozzles 10a and 10b was 16 m / s, and the ejection unevenness at each of the 21 points in the width direction perpendicular to the paper surface was 10a and 10b. It was 6%. The average inflow velocity at the insertion port 7 was 0.2 m / s.

(Comparative Example 1)
As shown in FIG. 6, the conventional air curtain means 8 was provided in the same heat treatment chamber 2 and seal chamber 4 as in the first embodiment. The nozzles 10 a and 10 b of the air curtain means 8 and 8 ′ include one perforated plate 18 and a flow rate adjusting chamber 23 as shown in FIG. 10. The aperture ratio of the porous plate 18 is 3%, which is almost the same as the pressure loss in the first embodiment. The ejection ports 20a and 20b of the nozzles 10a and 10b are the same as those in the first embodiment. The air curtain means 8 adjusted the average blown air speed from the nozzles 10a and 10b to 6 m / s, and then adjusted the exhaust amount by the exhaust fan 14 and the flow rate adjusting damper 13. At this time, ejection unevenness at 21 points in the width direction from the nozzles 10a and 10b was ± 10% of the average value for 10a and 10b. The pressure in the seal chamber 4 was −2.5 Pa, and the average inflow speed at the insertion port 7 was 0.3 m / s.

(Comparative Example 2)
It was the same as Comparative Example 1 except that the average blown wind speed from the nozzles 10a and 10b was 16 m / s.
As in Comparative Example 1, when adjustment was performed, the ejection unevenness at 21 points in the width direction from the nozzles 10a and 10b was ± 9% of the average value for 10a and 10b. The pressure in the seal chamber 4 was −7 Pa, and the average inflow speed at the insertion port 7 was 0.4 m / s.

  As shown in FIG. 7, the configuration was the same as that of Example 1 except that a simulated two-stage heat treatment chamber 2 was used. The upper air curtain means 8 had an average blowing air speed of 5 m / s from the nozzles 10a and 10b, and the lower air curtain means 8 'had an average blowing air speed of 16 m / s. The ejection unevenness is as shown in Examples 1 and 2.

  As in Examples 1 and 2, the pressure in the seal chamber 4 was adjusted so that the upper stage was −2 Pa and the lower stage was −6 Pa. Outside air flowed in all the locations of the upper and lower stages of the insertion port 7, and the average inflow speed was 0.2 m / s.

(Comparative Example 3)
As shown in FIG. 8, the configuration was the same as that of Comparative Example 1 except that a simulated two-stage heat treatment chamber 2 was used.
The upper air curtain means 8 had an average blowing air speed of 5 m / s from the nozzles 10a and 10b, and the middle and lower air curtain means 8 'and 8''had an average blowing air speed of 16 m / s. The ejection unevenness is as shown in Comparative Examples 1 and 2.

  As in Comparative Examples 1 and 2, the pressure in the seal chamber 4 was adjusted so that the upper stage was −2.5 Pa and the lower stage was −7 Pa. Outside air flowed into the lower part of the insertion port 7 at all points, and the average inflow speed was 0.4 m / s. However, the gas in the seal chamber 4 leaked to the outside at almost all locations in the upper stage.

(Comparative Example 4)
It was the same as Comparative Example 3 except that the average blowing wind speed from the nozzles 10a and 10b of the middle air curtain means 8 ′ was 5 m / s.
Outside air flowed in all places in the upper and lower stages of the insertion port 7. The average inflow velocity was 0.3 m / s in the upper stage and 1.5 m / s in the lower stage.

(Comparative Example 5)
It was the same as Comparative Example 3 except that the average blown air velocity from the nozzles 10a and 10b of the middle air curtain means 8 ′ was 10 m / s.
Outside air flowed into the lower part of the insertion port 7 at all points, and the average inflow speed was 1 m / s. In the upper stage, the gas in the seal chamber 4 leaked to the outside at almost all points.

It is a side view of the horizontal flameproofing furnace in embodiment of this invention, (a) is sectional drawing of the whole, (b) is a partial side view. It is sectional drawing to which the principal part of the air curtain means shown in FIG. 1 was expanded. It is a front view of the air curtain means shown in FIG. FIG. 3 is a cross-sectional view of the air curtain means shown in FIG. 1, wherein (a) is a cross-sectional view taken along line ii of FIG. It is sectional drawing of the simulated horizontal flame-proofing furnace (1st stage) of an Example. It is sectional drawing of the simulated horizontal flame-proofing furnace (1 step | paragraph) of a comparative example. It is sectional drawing of the simulated horizontal flameproofing furnace (2nd stage) of an Example. It is sectional drawing of the simulation horizontal flame-proofing furnace (2nd stage) of a comparative example. It is sectional drawing to which the principal part of the conventional air curtain means shown in FIG. 6 was expanded. It is sectional drawing of the nozzle of the conventional air curtain means shown in FIG.

Explanation of symbols

A Precursor fiber (object to be treated)
1 Flameproofing furnace (Horizontal flameproofing furnace)
2 Heat treatment room
4 Sealing chamber
5 outer wall 7 insertion slot 7 'insertion slot
10a nozzle
10b nozzle
18 Perforated plate (rectifying means)
19 Perforated plate (rectifying means)
35 Air supply path

Claims (8)

In a horizontal flameproofing furnace for continuously heat-treating an object to be processed in a heat-treatment chamber, a slit-like insertion port for inserting and inserting the object to be processed is inserted into an outer wall of a seal chamber connected to the heat-treatment chamber. A pair of nozzles are formed on the upper and lower sides of the insertion port so as to eject air toward the workpiece, and a flow rate adjusting mechanism is provided for each pair of nozzles. A horizontal flameproofing furnace characterized by connecting one air supply path.   2. The horizontal flameproofing furnace according to claim 1, further comprising a screen-like rectifier having a plurality of holes formed in the air supply passage.   3. The horizontal flameproof furnace according to claim 2, wherein the rectifying means uses one or both of a removable perforated plate and a net.   The horizontal flameproofing furnace according to any one of claims 1 to 3, wherein the air ejected from the nozzle is air outside the heat treatment chamber. In a flameproofing method using a horizontal flameproofing furnace for continuously heat-treating an object to be treated in a heat treatment chamber, the object to be treated is inserted at the time of insertion / extraction of the object to be heat-treated in the heat treatment chamber. A flameproofing process characterized in that air is supplied to each of a pair of upper and lower nozzles sandwiching the insertion port from a supply passage provided with a common flow rate adjusting mechanism in the vicinity of the insertion port, and ejected to the object to be processed Method.   A screen-like rectifier having a plurality of holes formed in the supply passage is provided, and the pressure distribution of the air in the air supply passage is made uniform to be ejected to the object to be processed by the nozzle. Item 6. A flameproofing treatment method according to Item 5.   Using one or both of a removable perforated plate and a mesh as the rectifying means, the pressure distribution of the air in the air supply path is made uniform, and the nozzle ejects the object to be processed. The flameproofing method according to claim 6.   The flameproofing method according to claim 5, wherein air outside the heat treatment chamber is ejected from the nozzle.

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