CN210826466U - Device for improving uniformity of temperature field of pre-oxidation furnace - Google Patents

Abstract

The utility model provides an improve device of pre-oxidation furnace temperature field homogeneity, it includes: the furnace body is provided with an outer furnace door (1) and an inner furnace door (6), the inner furnace door (6) is positioned inside the furnace body, and the inner side of the inner furnace door (6) forms a furnace chamber (8); the oven is characterized by further comprising a first communicating pipeline (100), one end of the first communicating pipeline (100) is communicated with the upper space of the oven cavity (8), the other end of the first communicating pipeline (100) is communicated to the lower space of the oven cavity (8), and a first fan (9) is further arranged on the first communicating pipeline (100). The utility model can ensure the uniformity of temperature difference and pressure field in the furnace chamber, especially between the upper part and the lower part, prevent external cold gas from entering the furnace chamber and high-temperature hot gas from being discharged out of the furnace, and does not need to remove tar regularly, thereby improving the production quality of carbon fiber; and effectively avoids and prevents the waste gas from being discharged to workshops through the inlet and outlet of the tows.

Description

Device for improving uniformity of temperature field of pre-oxidation furnace

Technical Field

The utility model belongs to the technical field of carbon fiber manufacturing, concretely relates to improve device of pre-oxidation furnace temperature field homogeneity.

Background

Carbon fiber is produced in the 50's of the last century, has various excellent properties of common carbon materials, and also has quite high specific strength and specific modulus, and is an excellent reinforcement of advanced composite materials. The development and application of the composite material are rapidly developed, and the composite material is widely applied to spacecrafts, artificial satellites, space shuttles, missiles, atomic energy, aviation and general civil industrial departments. At present, the carbon fiber production raw materials have three types: viscose, pitch and Polyacrylonitrile (PAN) fibers. PAN is used as a raw material to prepare carbon fiber, and the product has good mechanical property, simple production process and high carbonization yield, so the PAN is greatly developed and becomes the mainstream of the current carbon fiber industry.

The current industrial production operation is to pre-oxidize PAN protofilament by an air oxidation furnace with temperature gradient of 180-300 ℃ and then carbonize the pre-oxidized fiber in high-purity nitrogen with the maximum temperature of 1400-1600 ℃. If the pre-oxidized fibres are directly subjected to carbonization at temperatures above 1000 c, the fibre structure is destroyed by the intense thermal shock. In order to avoid the damage, before high-temperature carbonization, the pre-oxidized fiber is subjected to medium-low temperature carbonization heat treatment at 300-900 ℃, which is collectively called low-temperature carbonization. During pre-oxidation, particularly in the initial stage, the fiber is subjected to appropriate draft to inhibit shrinkage of PAN macromolecules and maintain the orientation of PAN macromolecule chains to the axial direction of the fiber. Meanwhile, with the rise of the pre-oxidation temperature, the interior of the fiber firstly generates complex chemical reactions such as cyclization, dehydrogenation, oxidation and the like of PAN macromolecules in an amorphous area and then in an ordered area, releases a large amount of heat, and finally forms a rigid stable trapezoid high molecular weight polymer structure oriented along the axial direction, so that the fiber has the capability of being not fused and incombustible and continuously keeping the fiber shape during high-temperature carbonization.

The pre-oxidation furnace has more types and can be divided into three types according to the air inlet mode: side-blowing, vertical-blowing, center-to-both-end blowing. Each oxidation furnace has respective advantages and disadvantages, the side-blowing type oxidation furnace is vertical to the tows, chemical reaction micromolecules and heat can be taken away instantly, and when the furnace body is wide, a certain air speed difference and a certain temperature difference exist at the inlet and outlet ends in the hearth; the vertical blowing type oxidation furnace blows air from the top, so that the uniformity of the air speed on the surfaces of the tows is ensured, but when a plurality of layers of tows exist in a fiber channel in the furnace and the gaps of the tows are reduced, hot air is difficult to pass through the tows, so that small reaction molecules and heat are difficult to take away; compared with the two types of oxidation furnaces, the blowing type oxidation furnace from the center to the two ends can not only ensure the uniformity of the wind speed on the surface of the tows, but also can take away heat instantly, the pre-oxidation efficiency is improved, but the manufacturing cost is expensive.

All kinds of preliminary oxidation stove both ends all have the access & exit through the silk bundle, and when the oxidation stove worked, because the inside malleation environment of furnace body, consequently no matter what kind of form oxidation stove can not avoid can discharging waste gas to the workshop through the access & exit of silk bundle. Hot gas overflows from a wire inlet and a wire outlet at the top of the oxidation furnace, and external gas enters the furnace from the bottom of the oxidation furnace and causes non-uniform temperature in the oxidation furnace; and after the cold process gas entering the furnace body exchanges heat with the hot gas generated by the reaction of the fibers, the gas generated by the reaction generates tar on the wire roller, the furnace body and the fibers, so that the tar needs to be removed periodically, and certain loss is caused to the production of the carbon fibers.

Because the temperature in the pre-oxidation furnace for producing carbon fibers in the prior art is uneven, external cold gas enters the furnace, and internal high-temperature hot gas is unnecessarily discharged out of the furnace; after the cold process gas entering the furnace body exchanges heat with the hot gas generated by the reaction of the fibers, the gas generated by the reaction generates tar on the wire roller, the furnace body and the fibers, so that the tar needs to be removed periodically, and certain loss is caused to the production of the carbon fibers; the oxidation furnace all can not avoid can discharging technical problem such as waste gas to the workshop through the access & exit of silk bundle, consequently the utility model discloses research design out a device that improves the homogeneity of pre-oxidation furnace temperature field.

SUMMERY OF THE UTILITY MODEL

Therefore, the to-be-solved technical problem of the utility model lies in overcoming the defect that has the inhomogeneous condition of temperature in the pre-oxidation furnace of carbon fiber production among the prior art to provide a device that improves pre-oxidation furnace temperature field homogeneity.

The utility model provides an improve device of pre-oxidation furnace temperature field homogeneity, it includes:

a furnace body having an outer door and an inner door, the inner door being located inside the furnace body, an inner side of the inner door being formed as a furnace chamber; the oven comprises an oven cavity and is characterized by further comprising a first communicating pipeline, one end of the first communicating pipeline is communicated with the upper space of the oven cavity, the other end of the first communicating pipeline is communicated to the lower space of the oven cavity, and a first fan is further arranged on the first communicating pipeline.

Preferably, the first and second electrodes are formed of a metal,

the oven comprises an inner oven door, an outer oven door and a plurality of communicating pipelines, wherein a middle cavity is formed between the inner oven door and the outer oven door, the communicating pipelines can communicate the upper space of the middle cavity with the lower space of the middle cavity, and the communicating pipelines are provided with second fans.

Preferably, the first and second electrodes are formed of a metal,

be provided with middle section sealing unit in the middle part cavity, in order to incite somebody to action the middle part cavity divide into first cavity and second cavity, first cavity is located outer furnace gate with between the sealing unit of middle section, the second cavity is located interior furnace gate with between the sealing unit of middle section, the sealing unit of middle section can be right first cavity with form sealedly between the second cavity.

Preferably, the first and second electrodes are formed of a metal,

the plurality of communicating pipes include a first pipe communicating with an upper portion of the first cavity and a second pipe communicating with a lower portion of the first cavity; and/or the plurality of communication pipelines further comprise a third pipeline communicated with the upper part of the second cavity and a fourth pipeline communicated with the lower part of the second cavity;

the plurality of communicating pipelines further comprise a fifth pipeline, the fifth pipeline is communicated between the first pipeline and the second pipeline, and/or the fifth pipeline is communicated between the third pipeline and the fourth pipeline, and the second fan is arranged on the fifth pipeline.

Preferably, the first and second electrodes are formed of a metal,

the first pipeline is communicated with the first communication pipeline through the first pipeline, and/or the second pipeline is communicated with the first communication pipeline through the second pipeline; and the sixth pipeline is provided with an on-off valve.

Preferably, the first and second electrodes are formed of a metal,

the first pipeline is arranged between the first pipeline and the second pipeline and is connected with the second fan in parallel, and a first three-way valve is arranged at the position where the first pipeline is connected with the second pipeline; and/or the third pipeline is arranged between the fifth pipeline and the fourth pipeline and connected with the second fan in parallel, and a second three-way valve is arranged at the position where the eighth pipeline is connected with the fourth pipeline.

Preferably, the first and second electrodes are formed of a metal,

the middle section sealing unit is a middle section air locking unit capable of exhausting air from the second cavity, the third pipeline is communicated with the upper portion of the middle section sealing unit, and the fourth pipeline is communicated with the lower portion of the middle section sealing unit.

Preferably, the first and second electrodes are formed of a metal,

the first pipeline is communicated with the upper part of the outer sealing unit, and the second pipeline is communicated with the lower part of the outer sealing unit.

Preferably, the first and second electrodes are formed of a metal,

the furnace door is characterized by further comprising an inner sealing unit which is arranged in the second cavity and close to the inner furnace door, the inner sealing unit is an inner air lock unit capable of exhausting air from the second cavity, and the third pipeline is further communicated with the inner sealing unit.

Preferably, the first and second electrodes are formed of a metal,

when the air lock device comprises a middle section air lock unit, the middle section air lock units are vertically arranged, and the third pipelines are respectively communicated with the middle section air lock units positioned at the upper part; the fourth pipeline is respectively communicated with the plurality of middle-section airlock units positioned at the lower part;

when the air locking device comprises the outer air locking units, the outer air locking units are vertically arranged, and the first pipelines are respectively communicated with the outer air locking units positioned at the upper part; the second pipeline is respectively communicated with the plurality of external air locking units positioned at the lower part.

The inner air lock units are vertically arranged in a plurality, and the third pipelines are respectively communicated with the inner air lock units.

The utility model provides a pair of improve device of pre-oxidation furnace temperature field homogeneity has following beneficial effect:

1. the utility model discloses a set up first intercommunication pipeline, in order to communicate upper portion space and lower part space in the furnace chamber, and cooperate first fan, can effectively leading-in to lower part with the highly compressed gas of high temperature of upper portion in the furnace chamber, and mix with the gas of the low temperature low pressure of furnace chamber lower part between, thereby guaranteed the homogeneity of the especially difference in temperature between the upper and lower part in the furnace chamber and the homogeneity of pressure field effectively, prevented that outside cold gas from getting into the furnace chamber, the hot gas of high temperature from discharging out of the stove has also been prevented, avoid and prevent to get into the cold process gas of furnace body and the hot gas heat transfer that the fibre reaction generated after, the reaction generated gas is at the fiber roll, the furnace body, the condition of producing tar on the fibre, need not regularly get rid of tar, improve carbon fiber; and effectively avoids and prevents the waste gas from being discharged to the workshop through the inlet and outlet of the tows;

2. the utility model discloses still through the middle part cavity between interior furnace gate and the outer furnace gate set up a plurality of intercommunication pipelines, in order to connect the upper portion space and the lower part space of middle part cavity, and cooperate the second fan, also can lead in the upper portion high temperature high-pressure gas in this middle part cavity to the low temperature low pressure gas of lower part, and mix, make the gas temperature field in this middle part cavity more even and pressure more even, further prevent that outside cold gas from entering the furnace intracavity, also prevented high temperature hot gas from discharging outside the stove, avoid the hot gas heat transfer that cold process gas and fibre reaction produced to produce the condition of tar on the fiber roll, furnace body, fibre, improve carbon fiber production quality; and effectively avoids and prevents the waste gas from being discharged to the workshop through the inlet and outlet of the tows;

3. the utility model discloses still can seal the separation with middle part cavity through setting up middle section sealing unit, and use middle section airlock unit can extract the gas in the second cavity and make the third pipeline still communicate with middle section airlock unit upper portion, the fourth pipeline still communicates with middle section airlock unit lower part, thus further suck the upper portion gas in the second cavity and lead to the second cavity lower part, make the gas temperature field in the second cavity and pressure field distribute more evenly;

by using the external sealing unit and preferably the external air locking unit, the gas in the first cavity can be extracted, the first pipeline is also communicated with the upper part of the external air locking unit, and the second pipeline is also communicated with the lower part of the external air locking unit, so that the gas at the upper part in the first cavity is further sucked and guided to the lower part of the first cavity, and the distribution of a gas temperature field and a gas pressure field in the first cavity is more uniform;

and by using the inner sealing unit and preferably the inner air lock unit, the gas in the second cavity can be extracted and the third pipeline is also communicated with the inner air lock unit, so that the gas at the upper part in the second cavity is further sucked and guided to the lower part of the second cavity through the fifth pipeline and the fourth pipeline, and the temperature field and the pressure field of the gas in the second cavity are distributed more uniformly;

4. the utility model discloses still through setting up the seventh pipeline parallelly connected with the second fan, the eighth pipeline, and first and second three-way valve, and combine the setting of sixth pipeline, can with the upper portion gas and the lower part gas common suction (whole suction) in the middle part cavity between outer furnace gate and the interior furnace gate to the main loop pipeline (with the first intercommunication pipeline of furnace chamber intercommunication), also can guarantee the homogeneity of temperature field and pressure field in the middle part cavity effectively, improve the degree of consistency of fibre pre-oxidation, the off-the-shelf intensity of fibre and modulus have been promoted.

Drawings

Fig. 1 is a schematic structural diagram of the device for improving the uniformity of the temperature field of the pre-oxidation furnace of the present invention.

The reference numbers in the figures denote:

1. an outer oven door; 2. an outer sealing unit; 3. a middle section air lock frame; 4. a middle section sealing unit; 5. an inner sealing unit; 6. an inner oven door; 7. a heat-insulating layer; 8. a furnace chamber; 9. a first fan; 10. an on-off valve; 11. a first three-way valve; 12. a second three-way valve; 13. a second fan; 14. a first cavity; 15. a second cavity; 100. a first communicating pipe; 101. a first pipeline; 102. a second pipeline; 103. a third pipeline; 104. a fourth pipeline; 105. a fifth pipeline; 106. a sixth pipeline; 107. a seventh pipeline; 108. and an eighth pipeline.

Detailed Description

As shown in fig. 1, the utility model provides a device for improving the uniformity of the temperature field of a pre-oxidation furnace, which comprises: the furnace body is provided with an outer furnace door 1 and an inner furnace door 6, the inner furnace door 6 is positioned in the furnace body, and the inner side of the inner furnace door 6 is formed into a furnace chamber 8; the oven is characterized by further comprising a first communication pipeline 100, one end of the first communication pipeline 100 is communicated with the upper space of the oven cavity 8, the other end of the first communication pipeline 100 is communicated with the lower space of the oven cavity 8, and a first fan 9 is further arranged on the first communication pipeline 100.

The first communication pipeline is arranged to communicate the upper space with the lower space in the furnace chamber, and the first fan is matched to effectively guide the high-temperature and high-pressure gas at the upper part of the furnace chamber into the lower part of the furnace chamber and mix the high-temperature and high-pressure gas with the low-temperature and low-pressure gas at the lower part of the furnace chamber, so that the uniformity of temperature difference and the uniformity of pressure field in the furnace chamber, particularly between the upper part and the lower part of the furnace chamber, are effectively ensured, external cold gas is further prevented from entering the furnace chamber, high-temperature hot gas is also prevented from being discharged out of the furnace, the condition that the gas generated by reaction generates tar on a wire roller, the furnace body and fibers after heat exchange between cold process gas entering the furnace body and hot gas generated by fiber reaction is avoided and prevented; and effectively avoids and prevents the waste gas from being discharged to workshops through the inlet and outlet of the tows.

Preferably, the first and second electrodes are formed of a metal,

a middle cavity is formed between the inner furnace door 6 and the outer furnace door 1, the furnace further comprises a plurality of communicating pipelines which can communicate the upper space of the middle cavity with the lower space of the middle cavity, and the plurality of communicating pipelines are provided with second fans 13. A plurality of communicating pipelines are arranged in the middle cavity between the inner furnace door and the outer furnace door to connect the upper space and the lower space of the middle cavity, and a second fan is matched to guide the upper high-temperature high-pressure gas in the middle cavity into the lower low-temperature low-pressure gas and mix the gas, so that the gas temperature field in the middle cavity is more uniform and the pressure is more uniform, external cold gas is further prevented from entering the furnace cavity, high-temperature hot gas is also prevented from being discharged out of the furnace, the condition that tar is generated on a wire roller, a furnace body and fibers due to heat exchange of hot gas generated by the reaction of cold process gas and the fibers is avoided, and the production quality of carbon fibers is improved; and effectively avoids and prevents the waste gas from being discharged to workshops through the inlet and outlet of the tows.

Preferably, the first and second electrodes are formed of a metal,

be provided with middle section sealing unit 4 in the middle part cavity, will the middle part cavity divide into first cavity 14 and second cavity 15, first cavity 14 is located outer furnace door 1 with between the sealing unit 4 of middle section, second cavity 15 is located interior furnace door 6 with between the sealing unit 4 of middle section, the sealing unit 4 of middle section can be right first cavity 14 with form sealedly between the second cavity 15. Can form effective sealed the separating into two cavitys to the middle part cavity through setting up middle section seal unit to carry out gas guide effect respectively to two different cavitys, make the middle part cavity form and divide, carry out the control of temperature field homogeneity to every cavity that divides, the temperature field homogeneity effect of every cavity is better.

Preferably, the first and second electrodes are formed of a metal,

the plurality of communication pipes includes a first pipe 101 communicating with an upper portion of the first cavity 14 and a second pipe 102 communicating with a lower portion of the first cavity 14; and/or, the plurality of communication pipes further comprises a third pipe 103 communicating with the upper part of the second cavity 15 and a fourth pipe 104 communicating with the lower part of the second cavity 15;

the plurality of communication pipelines further include a fifth pipeline 105, the fifth pipeline 105 is communicated between the first pipeline 101 and the second pipeline 102, and/or the fifth pipeline 105 is communicated between the third pipeline 103 and the fourth pipeline 104, and the second fan 13 is disposed on the fifth pipeline 105.

This is the utility model discloses a realize preferred structural style of gaseous water conservancy diversion, take out first cavity upper portion gas through first pipeline, and through the water conservancy diversion of fifth pipeline, leading-in to the lower part of first cavity through the second pipeline, realize gaseous upper and lower portion and mix, improve first cavity temperature field homogeneity, likewise, take out second cavity upper portion gas through the third pipeline, and through the water conservancy diversion of fifth pipeline, leading-in to the lower part of second cavity through the fourth pipeline, realize gaseous upper and lower portion and mix, improve second cavity temperature field homogeneity.

Preferably, the first and second electrodes are formed of a metal,

a sixth pipeline 106 is further included, the sixth pipeline 106 communicates the second pipeline 102 with the first communication pipeline 100, and/or the sixth pipeline 106 communicates the fourth pipeline 104 with the first communication pipeline 100; the sixth pipeline 106 is provided with an on-off valve 10. The sixth pipeline is arranged to realize the conduction between the main circulation pipeline (the first communication pipeline communicated with the furnace chamber) and the airlock circulation pipeline (a plurality of pipelines communicated with the middle cavity), so that the gas at the upper part and the lower part of the middle cavity between the inner furnace door and the outer furnace door is pumped away and guided into the furnace chamber when in demand, and the uniformity of the gas temperature field and the uniformity of the pressure field inside the furnace chamber and the middle cavity can be realized.

Preferably, the first and second electrodes are formed of a metal,

the third pipeline 107 is arranged between the fifth pipeline 105 and the second pipeline 102 and connected with the second fan 13 in parallel, and a first three-way valve 11 is arranged at the position where the seventh pipeline 107 is connected with the second pipeline 102; and/or the third pipeline 108 is arranged between the fifth pipeline 105 and the fourth pipeline 104 and connected with the second fan 13 in parallel, and a second three-way valve 12 is arranged at the position where the eighth pipeline 108 is connected with the fourth pipeline 104.

Still through setting up the seventh pipeline, the eighth pipeline parallelly connected with the second fan to and first and second three-way valve, and combine the setting of sixth pipeline, can suck upper portion gas and lower part gas in the middle part cavity between outer furnace door and the interior furnace door jointly (whole suction) to the main loop pipeline (with the first intercommunication pipeline of furnace chamber intercommunication), also can guarantee the homogeneity in temperature field and the pressure field in the middle part cavity effectively, improve the degree of consistency of fibre preoxidation, promoted the finished intensity and the modulus of fibre.

Preferably, the first and second electrodes are formed of a metal,

the middle section sealing unit 4 is a middle section airlock unit capable of exhausting air from the second cavity 15, the third pipeline 103 is further communicated with the upper part of the middle section sealing unit 4, and the fourth pipeline 104 is further communicated with the lower part of the middle section sealing unit 4.

Through using the middle section airlock unit that can bleed to the second cavity can extract the gas in the second cavity and make the third pipeline still communicate with middle section airlock unit upper portion, fourth pipeline still with middle section airlock unit lower part intercommunication to further to upper portion gas is sucked and is leading-in to the second cavity lower part in the second cavity, makes the gas temperature field in the second cavity and pressure field distribute more evenly.

Preferably, the first and second electrodes are formed of a metal,

the oven door structure further comprises an outer sealing unit 2 which is arranged in the first cavity 14 and close to the outer oven door 1, the outer sealing unit 2 is an outer air lock unit capable of exhausting air from the first cavity 14, the first pipeline 101 is further communicated with the upper portion of the outer sealing unit 2, and the second pipeline 102 is further communicated with the lower portion of the outer sealing unit 2.

Through using the external sealing unit and preferably the outer air lock unit, the gas in the first cavity can be extracted, the first pipeline is also communicated with the upper part of the outer air lock unit, and the second pipeline is also communicated with the lower part of the outer air lock unit, so that the gas at the upper part in the first cavity is further sucked and guided into the lower part of the first cavity, and the distribution of the gas temperature field and the pressure field in the first cavity is more uniform.

Preferably, the first and second electrodes are formed of a metal,

the oven door structure further comprises an inner sealing unit 5 which is arranged in the second cavity 15 and close to the inner oven door 6, the inner sealing unit 5 is an inner air locking unit capable of exhausting air from the second cavity 15, and the third pipeline 103 is further communicated with the inner sealing unit 5. Through using the internal sealing unit, preferably the internal air locking unit, the gas in the second cavity can be extracted, and the third pipeline is also communicated with the internal air locking unit, so that the gas at the upper part in the second cavity is further sucked and guided into the lower part of the second cavity through the fifth pipeline and the fourth pipeline, and the distribution of the gas temperature field and the pressure field in the second cavity is more uniform.

Preferably, the first and second electrodes are formed of a metal,

when the air lock unit comprises a plurality of middle air lock units, the middle air lock units are vertically arranged, and the third pipeline 103 is respectively communicated with the middle air lock units positioned at the upper part; the fourth pipeline 104 is respectively communicated with the plurality of middle-section airlock units positioned at the lower part;

when the air locking device comprises a plurality of outer air locking units, the plurality of outer air locking units are vertically arranged, and the first pipeline 101 is respectively communicated with the plurality of outer air locking units positioned at the upper part; the second pipeline 102 is respectively communicated with a plurality of external air locking units positioned at the lower part;

the inner air lock units are vertically arranged in a plurality, and the third pipeline 103 is communicated with the inner air lock units respectively.

The middle section airlock unit, the outer airlock unit and the inner airlock unit are respectively optimized, and the airlock units are arranged in a split mode, so that the airlock units can perform sectional air suction and generate air sealing in the height direction, and the suction and sealing effects in a local range are realized, the uniformity of the suction effect and the uniformity of the sealing effect can be realized in the whole cavity, and the uniformity of the air temperature field in the cavity is improved.

The utility model discloses to prior art's not enough, provided a device of improvement pre-oxidation stove temperature field homogeneity, prevent that hot-blast from overflowing from the fire door, cold wind gets into the fire door, guarantees the homogeneity of the internal temperature of furnace and what of oxygen content, satisfies the air-tight requirement of different grade type oxidation stoves, has improved the degree of consistency of fibre pre-oxidation, has promoted the off-the-shelf intensity of fibre and modulus.

The utility model discloses a device for improving the uniformity of a temperature field of a pre-oxidation furnace, which comprises an oxidation furnace body, a heat insulation door in the furnace body and a heat insulation door outside the furnace body; the air seal equipment comprises an outer furnace door air lock unit, a middle section air lock unit and an inner furnace door air lock unit; the furnace body is connected with a circulating fan to realize a blowing structure of the oxidation furnace from top to bottom.

The embodiment is a vertical blowing type oxidation furnace, the pre-oxidation furnace comprises a furnace chamber 8, and the furnace chamber 8 is connected with a circulating pipeline of a first fan 9, so that vertical blowing is realized. The furnace chamber 8 is externally provided with a furnace body insulating layer 7. The heat-insulating inner furnace door 6 is arranged outside the furnace body. The air seal equipment comprises an inner seal unit 5 (preferably an inner furnace door air lock unit), a middle section seal unit 4 (preferably a middle section air lock unit), a middle section air lock frame 3 (for supporting the middle section air lock unit) and an outer seal unit 2 (preferably an outer furnace door air lock unit), and the outermost side is a heat-insulating outer furnace door 1. The air seal equipment pipeline comprises an air lock pipeline connected with a second fan 13, a first three-way valve 11 and a second three-way valve 12 are connected on the air lock pipeline, and a on-off valve 10 is used for communicating the air lock pipeline with a circulating pipeline. The air seal equipment also comprises a pressure gauge for measuring gas, so that the pressure is accurately controlled.

In the operation process of the oxidation furnace, if no gas seal is arranged, under the action of the internal pressure of the furnace, the upper half part of the furnace opening is greatly exhausted, the lower half part is greatly exhausted, and the gas inlet and outlet phenomena are more obvious when the pressure difference in the furnace is larger. The air sealing device comprises a second fan (preferably an air locking fan), a three-way valve and an on-off valve 10 (preferably an on-off butterfly valve) which are connected.

Example 1, the closing of the on-off valve 10 and the opening of the a, b connecting the a, b of the first three-way valve 11 and the a, b of the second three-way valve 12 are achieved by collecting the gas escaping from the furnace from the upper part in advance and sending the gas to the lower part of the furnace mouth through a pipeline. The pressure difference between the upper part and the lower part of the pressure gauge is controlled within 10 Pa. Certain local high pressure is formed, so that the gas outside the furnace can not enter the furnace, an independent gas seal circulation is formed, no extra energy consumption is caused, the purpose of ensuring a constant temperature section in the furnace is achieved, and the uniformity of a temperature field of the oxidation furnace is improved.

Example 2, the on-off valve 10 is opened, and the gas in the upper and lower parts of the implementation scheme two, which is connected with the a and c of the first three-way valve 11 and the a and c of the second three-way valve 12, is all pumped into the main circulation pipeline. The pressure difference between the upper part and the lower part of the pressure gauge is controlled within 10 Pa. Therefore, independent air-sealed circulation can be realized, the purpose of ensuring the constant temperature section in the furnace is achieved, the uniformity of the temperature field of the oxidation furnace is improved, and the energy-saving effect is obvious.

The pre-oxidation furnace is a side-blowing oxidation furnace, a vertical-blowing oxidation furnace or a center-to-two-end blowing oxidation furnace. The circulating pipeline is provided with a circulating fan, and the pipeline of the gas-gas sealing equipment is provided with an air lock fan. The fans are controlled by frequency converters. The three-way valve and the on-off butterfly valve are manually controlled, and the operation and maintenance are simple.

The utility model has the advantages that:

the air sealing requirements of different types of oxidation furnaces are met by switching different airlock pipelines, the degree of uniformity of fiber pre-oxidation is improved, and the strength and modulus of fiber finished products are improved. The switch through tee bend valve and break-make butterfly valve can realize the switching of two operation modes of airlock equipment, reduces the regional inside difference in temperature of oxidation furnace, improves the homogeneity of pre-oxidation furnace temperature field, has guaranteed that pre-oxidation fibre quality has improved production efficiency, cuts this device simple structure, and is with low costs.

The overflow of waste gas from the inlet and the outlet of the tows is reduced, tar generated by reaction generated gas on the wire roller, the furnace body and the fibers is reduced, the operation efficiency of the production line is improved, the quality of carbon fibers is improved, and the production cost is reduced.

The above description is only exemplary of the present invention and should not be taken as limiting the scope of the present invention, as any modifications, equivalents, improvements and the like made within the spirit and principles of the present invention are intended to be included within the scope of the present invention. The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims (10)

1. The utility model provides a improve device of pre-oxidation stove temperature field homogeneity which characterized in that: the method comprises the following steps:

the furnace body is provided with an outer furnace door (1) and an inner furnace door (6), the inner furnace door (6) is positioned inside the furnace body, and the inner side of the inner furnace door (6) forms a furnace chamber (8); the oven is characterized by further comprising a first communicating pipeline (100), one end of the first communicating pipeline (100) is communicated with the upper space of the oven cavity (8), the other end of the first communicating pipeline (100) is communicated to the lower space of the oven cavity (8), and a first fan (9) is further arranged on the first communicating pipeline (100).

2. The device for improving the temperature field uniformity of the pre-oxidation furnace according to claim 1, wherein:

a middle cavity is formed between the inner furnace door (6) and the outer furnace door (1), the furnace further comprises a plurality of communicating pipelines which can communicate the upper space of the middle cavity with the lower space of the middle cavity, and second fans (13) are arranged on the communicating pipelines.

3. The apparatus for improving the temperature field uniformity of the pre-oxidation furnace according to claim 2, wherein:

be provided with middle section sealing unit (4) in the middle part cavity, will the middle part cavity divide into first cavity (14) and second cavity (15), first cavity (14) are located outer furnace door (1) with between middle section sealing unit (4), second cavity (15) are located interior furnace door (6) with between middle section sealing unit (4), middle section sealing unit (4) can be right first cavity (14) with form sealedly between second cavity (15).

4. The apparatus for improving the temperature field uniformity of the pre-oxidation furnace as claimed in claim 3, wherein:

the plurality of communication lines includes a first line (101) communicating with an upper portion of the first cavity (14) and a second line (102) communicating with a lower portion of the first cavity (14); and/or the plurality of communication pipes further comprises a third pipe (103) communicating with the upper part of the second cavity (15) and a fourth pipe (104) communicating with the lower part of the second cavity (15);

the plurality of communication pipelines further comprise a fifth pipeline (105), the fifth pipeline (105) is communicated between the first pipeline (101) and the second pipeline (102), and/or the fifth pipeline (105) is communicated between the third pipeline (103) and the fourth pipeline (104), and the second fan (13) is arranged on the fifth pipeline (105).

5. The apparatus for improving the temperature field uniformity of the pre-oxidation furnace as claimed in claim 4, wherein:

further comprising a sixth pipeline (106), the sixth pipeline (106) communicating between the second pipeline (102) and the first communication pipeline (100), and/or the sixth pipeline (106) communicating between the fourth pipeline (104) and the first communication pipeline (100); and an on-off valve (10) is arranged on the sixth pipeline (106).

6. The apparatus for improving the temperature field uniformity of the pre-oxidation furnace as claimed in claim 5, wherein:

the system also comprises a seventh pipeline (107) which is arranged between the fifth pipeline (105) and the second pipeline (102) and is connected with the second fan (13) in parallel, and a first three-way valve (11) is arranged at the position where the seventh pipeline (107) is connected with the second pipeline (102); and/or the system also comprises an eighth pipeline (108) which is arranged between the fifth pipeline (105) and the fourth pipeline (104) and is connected with the second fan (13) in parallel, and a second three-way valve (12) is arranged at the position where the eighth pipeline (108) is connected with the fourth pipeline (104).

7. The apparatus for improving the temperature field uniformity of the pre-oxidation furnace as claimed in claim 4, wherein:

the middle section sealing unit (4) is a middle section air locking unit capable of exhausting air from the second cavity (15), the third pipeline (103) is communicated with the upper portion of the middle section sealing unit (4), and the fourth pipeline (104) is communicated with the lower portion of the middle section sealing unit (4).

8. The apparatus for improving the temperature field uniformity of the pre-oxidation furnace as claimed in claim 4, wherein:

the oven door is characterized by further comprising an outer sealing unit (2) which is arranged in the first cavity (14) and close to the outer oven door (1), the outer sealing unit (2) is an outer air lock unit capable of exhausting air from the first cavity (14), the first pipeline (101) is communicated with the upper portion of the outer sealing unit (2), and the second pipeline (102) is communicated with the lower portion of the outer sealing unit (2).

9. The apparatus for improving the temperature field uniformity of the pre-oxidation furnace as claimed in claim 4, wherein:

the oven door structure is characterized by further comprising an inner sealing unit (5) which is arranged in the second cavity (15) and close to the inner oven door (6), the inner sealing unit (5) is an inner air locking unit capable of exhausting air from the second cavity (15), and the third pipeline (103) is communicated with the inner sealing unit (5).

10. The apparatus for improving the temperature field uniformity of the pre-oxidation furnace according to any one of claims 7 to 9, wherein:

when the air lock device comprises a middle section air lock unit, the middle section air lock units are vertically arranged, and the third pipeline (103) is respectively communicated with the middle section air lock units positioned at the upper part; the fourth pipeline (104) is respectively communicated with the plurality of middle-section airlock units positioned at the lower part;

when the air locking device comprises a plurality of outer air locking units, the plurality of outer air locking units are vertically arranged, and the first pipeline (101) is respectively communicated with the plurality of outer air locking units positioned at the upper part; the second pipeline (102) is respectively communicated with a plurality of external air locking units positioned at the lower part;

when the air locking device comprises an inner air lock unit, the inner air lock unit is a plurality of air lock units which are vertically arranged, and the third pipeline (103) is communicated with the inner air lock units respectively.

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